LLM-GalaxyClusters.bib

@article{fabian_chandra_2000,
	title = {Chandra imaging of the complex {X}-ray core of the {Perseus} cluster},
	volume = {318},
	issn = {0035-8711, 1365-2966},
	url = {https://academic.oup.com/mnras/article/318/4/L65/958860},
	doi = {10.1046/j.1365-8711.2000.03904.x},
	abstract = {We report subarcsec-resolution X-ray imaging of the core of the Perseus cluster around the galaxy NGC 1275 with the Chandra X-ray Observatory. The ROSAT-discovered holes associated with the radio lobes have X-ray bright rims which are cooler than the surrounding gas and not a result of shocks. The holes themselves may contain some hotter gas. We map strong photoelectric absorption across the northern lobe and rim owing to a small infalling irregular galaxy, known as the high-velocity system. Two outer holes, one of which was previously known, are identified with recently found spurs of low-frequency radio emission. The spiral appearance of the X-ray cooler gas and the outer optical parts of NGC 1275 may be due to angular momentum in the cooling flow.},
	language = {en},
	number = {4},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Fabian, A. C. and Sanders, J. S. and Ettori, S. and Taylor, G. B. and Allen, S. W. and Crawford, C. S. and Iwasawa, K. and Johnstone, R. M. and Ogle, P. M.},
	month = nov,
	year = {2000},
	pages = {L65--L68},
	file = {Fabian et al. - 2000 - Chandra imaging of the complex X-ray core of the P.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/876ZLI6X/Fabian et al. - 2000 - Chandra imaging of the complex X-ray core of the P.pdf:application/pdf},
}

@article{ferland_collisional_2009,
	title = {Collisional heating as the origin of filament emission in galaxy clusters},
	volume = {392},
	issn = {00358711, 13652966},
	url = {http://arxiv.org/abs/0810.5372},
	doi = {10.1111/j.1365-2966.2008.14153.x},
	abstract = {It has long been known that photoionization, whether by starlight or other sources, has difficulty in accounting for the observed spectra of the optical filaments that often surround central galaxies in large clusters. This paper builds on the first of this series in which we examined whether heating by energetic particles or dissipative MHD wave can account for the observations. The first paper focused on the molecular regions which produce strong H2 and CO lines. Here we extend the calculations to include atomic and low-ionization regions. Two major improvements to the previous calculations have been made. The model of the hydrogen atom, along with all elements of the H-like iso-electronic sequence, is now fully nl-resolved. This allows us to predict the hydrogen emission-line spectrum including excitation by suprathermal secondary electrons and thermal electrons or nuclei. We show how the predicted H I spectrum differs from the pure recombination case. The second update is to the rates for H0 {\textendash} H2 inelastic collisions. We now use the values computed by Wrathmall et al. The rates are often much larger and allow the ro-vibrational H2 level populations to achieve a thermal distribution at substantially lower densities than previously thought.},
	language = {en},
	number = {4},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Ferland, G. J. and Fabian, A. C. and Hatch, N. A. and Johnstone, R. M. and Porter, R. L. and van Hoof, P. A. M. and Williams, R. J. R.},
	month = feb,
	year = {2009},
	note = {arXiv:0810.5372 [astro-ph]},
	keywords = {Astrophysics},
	pages = {1475--1502},
	file = {Ferland et al. - 2009 - Collisional heating as the origin of filament emis.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/87AAICKB/Ferland et al. - 2009 - Collisional heating as the origin of filament emis.pdf:application/pdf},
}

@article{salome_very_2011,
	title = {A very extended molecular web around {NGC} 1275},
	volume = {531},
	issn = {0004-6361, 1432-0746},
	url = {http://arxiv.org/abs/1105.3108},
	doi = {10.1051/0004-6361/200811333},
	abstract = {We present the first detection of CO emission lines in the H$\alpha$ filaments at distances as far as 50 kpc from the centre of the galaxy NGC 1275. This gas is probably dense (>=103cm-3). However, it is not possible to accurately determine the density and the kinetic temperature of this relatively warm gas (Tkin\~{} 20-500 K) with the current data only. The amount of molecular gas in the filaments is large {\textemdash} 109 M?(assuming a Galactic N(H2)/ICO ratio). This is 10\% of the total mass of molecular gas detected in this cD galaxy. This gas has large-scale velocities comparable to those seen in H$\alpha$. The origin of the filaments is still unclear, but their formation is very likely linked to the AGN positive feedback (Revaz et al., 2008) that regulates the cooling of the surrounding X-ray-emitting gas as suggested by numerical simulations. We also present high-resolution spectra of the galaxy core. The spatial characteristics of the double-peaked profile suggest that the molecular web of filaments and streamers penetrates down to radii of less than 2 kpc from the central AGN and eventually feed the galaxy nucleus. The mass of gas inside the very central region is \~{}109 M?, and is similar to the mass of molecular gas found in the filaments.},
	language = {en},
	urldate = {2024-05-26},
	journal = {Astronomy \& Astrophysics},
	author = {Salom{\'e}, P. and Combes, F. and Revaz, Y. and Downes, D. and Edge, A. C. and Fabian, A. C.},
	month = jul,
	year = {2011},
	note = {arXiv:1105.3108 [astro-ph]},
	keywords = {Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {A85},
	file = {Salom{\'e} et al. - 2011 - A very extended molecular web around NGC 1275.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/HCRNNPKV/Salom{\'e} et al. - 2011 - A very extended molecular web around NGC 1275.pdf:application/pdf},
}

@article{russell_alma_2017,
	title = {{ALMA} observations of massive molecular gas filaments encasing radio bubbles in the {Phoenix} cluster},
	volume = {836},
	issn = {0004-637X, 1538-4357},
	url = {http://arxiv.org/abs/1611.00017},
	doi = {10.3847/1538-4357/836/1/130},
	abstract = {We report new ALMA observations of the CO(3-2) line emission from the 2.1 {\textpm} 0.3 {\texttimes} 1010 M molecular gas reservoir in the central galaxy of the Phoenix cluster. The cold molecular gas is fuelling a vigorous starburst at a rate of 500-800 M yr-1 and powerful black hole activity in the form of both intense quasar radiation and radio jets. The radio jets have inflated huge bubbles filled with relativistic plasma into the hot, X-ray atmospheres surrounding the host galaxy. The ALMA observations show that extended filaments of molecular gas, each 10 - 20 kpc long with a mass of several billion solar masses, are located along the peripheries of the radio bubbles. The smooth velocity gradients and narrow line widths along each filament reveal massive, ordered molecular gas flows around each bubble, which are inconsistent with gravitational free-fall. The molecular clouds have been lifted directly by the radio bubbles, or formed via thermal instabilities induced in low entropy gas lifted in the updraft of the bubbles. These new data provide compelling evidence for close coupling between the radio bubbles and the cold gas, which is essential to explain the self-regulation of feedback. The very feedback mechanism that heats hot atmospheres and suppresses star formation may also paradoxically stimulate production of the cold gas required to sustain feedback in massive galaxies.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Russell, H. R. and McDonald, M. and McNamara, B. R. and Fabian, A. C. and Nulsen, P. E. J. and Bayliss, M. B. and Benson, B. A. and Brodwin, M. and Carlstrom, J. E. and Edge, A. C. and Hlavacek-Larrondo, J. and Marrone, D. P. and Reichardt, C. L. and Vieira, J. D.},
	month = feb,
	year = {2017},
	note = {arXiv:1611.00017 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {130},
	file = {Russell et al. - 2017 - ALMA observations of massive molecular gas filamen.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/ZRSX3IB5/Russell et al. - 2017 - ALMA observations of massive molecular gas filamen.pdf:application/pdf},
}

@article{russell_driving_2019,
	title = {Driving massive molecular gas flows in central cluster galaxies with {AGN} feedback},
	volume = {490},
	issn = {0035-8711, 1365-2966},
	url = {http://arxiv.org/abs/1902.09227},
	doi = {10.1093/mnras/stz2719},
	abstract = {We present an analysis of new and archival ALMA observations of molecular gas in twelve central cluster galaxies. We examine emerging trends in molecular filament morphology and gas velocities to understand their origins. Molecular gas masses in these systems span 109 - 1011 M , far more than most gas-rich galaxies. ALMA images reveal a distribution of morphologies from filamentary to disk-dominated structures. Circumnuclear disks on kiloparsec scales appear rare. In most systems, half to nearly all of the molecular gas lies in filamentary structures with masses of a few {\texttimes}108-10 M that extend radially several to several tens of kpc. In nearly all cases the molecular gas velocities lie far below stellar velocity dispersions, indicating youth, transience or both. Filament bulk velocities lie far below the galaxy{\textquoteright}s escape and free-fall speeds indicating they are bound and being decelerated. Most extended molecular filaments surround or lie beneath radio bubbles inflated by the central AGN. Smooth velocity gradients found along the filaments are consistent with gas flowing along streamlines surrounding these bubbles. Evidence suggests most of the molecular clouds formed from low entropy X-ray gas that became thermally unstable and cooled when lifted by the buoyant bubbles. Uplifted gas will stall and fall back to the galaxy in a circulating flow. The distribution in morphologies from filament to disk-dominated sources therefore implies slowly evolving molecular structures driven by the episodic activity of the AGN.},
	language = {en},
	number = {3},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Russell, H. R. and McNamara, B. R. and Fabian, A. C. and Nulsen, P. E. J. and Combes, F. and Edge, A. C. and Madar, M. and Olivares, V. and Salome, P. and Vantyghem, A. N.},
	month = dec,
	year = {2019},
	note = {arXiv:1902.09227 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena},
	pages = {3025--3045},
	file = {Russell et al. - 2019 - Driving massive molecular gas flows in central clu.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/KYMC8KYX/Russell et al. - 2019 - Driving massive molecular gas flows in central clu.pdf:application/pdf},
}

@article{imazato_origin_2021,
	title = {Origin of the {UV} to {X}-ray emission of radio galaxy {NGC} 1275 explored by analyzing its variability},
	volume = {906},
	issn = {0004-637X, 1538-4357},
	url = {http://arxiv.org/abs/2011.10299},
	doi = {10.3847/1538-4357/abc7bc},
	abstract = {We analyze the ultraviolet (UV) and X-ray data of NGC 1275 obtained with Swift/UVOT, XRT, BAT and Fermi Large Area Telescope over about 10 years to investigate the origin of the nuclear emission from NGC 1275. We confirm that the UV and soft/hard X-ray fluxes gradually increased along with the GeV gamma rays. At times, short-term variations in the UV or soft X-ray spectral regions showed rapid variations correlated with the GeV gamma-rays. However there was no significant correlation between the UV and soft X-rays. The UV spectrum had a narrow spectral shape that could be represented by singletemperature blackbody radiation. These results could possibly indicate that the long-term variability of UV and X-ray emissions is caused by the jet, while the emissions from the accretion disk contribute to the UV and X-ray bands to some extent.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Imazato, Fumiya and Fukazawa, Yasushi and Sasada, Mahito and Sakamoto, Takanori},
	month = jan,
	year = {2021},
	note = {arXiv:2011.10299 [astro-ph]},
	keywords = {Astrophysics - High Energy Astrophysical Phenomena},
	pages = {30},
	file = {Imazato et al. - 2021 - Origin of the UV to X-ray emission of radio galaxy.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/E457RCZ5/Imazato et al. - 2021 - Origin of the UV to X-ray emission of radio galaxy.pdf:application/pdf},
}

@article{gulati_multiwavelength_2021,
	title = {Multiwavelength monitoring of {NGC} 1275 over a decade: {Evidence} of a shift in synchrotron peak frequency and long-term multi-band flux increase},
	volume = {503},
	issn = {0035-8711, 1365-2966},
	shorttitle = {Multiwavelength monitoring of {NGC} 1275 over a decade},
	url = {http://arxiv.org/abs/2101.11540},
	doi = {10.1093/mnras/stab244},
	abstract = {We carried out a detailed study of the temporal and broadband spectral behaviour of one of the brightest misaligned active galaxies in -rays, NGC 1275 utilising 11 years of Fermi, and available Swift and AstroSat observations. Based on the cumulative flux distribution of the ray lightcurve, we identified four distinct activity states and noticed an increase in the baseline flux during the first three states. Similar nature of the increase in the average flux was also noticed in X-ray and UV bands. A large flaring activity in -rays was noticed in the fourth state. The source was observed twice by AstroSat for shorter intervals (\~{}days) during the longer observing periods (\~{}years) state 3 and 4. During AstroSat observing periods, the source -ray flux was higher than the average flux observed during longer duration states. The increase in the average baseline flux from state 1 to state 3 can be explained considering a corresponding increase of jet particle normalisation. The inverse Comptonisation of synchrotron photons explained the average X-ray and -ray emission by jet electrons during the first three longer duration states. However, during the shorter duration AstroSat observing periods, a shift of the synchrotron peak frequency was noticed, and the synchrotron emission of jet electrons well explained the observed X-ray flux.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Gulati, Sanna and Bhattacharya, Debbijoy and Bhattacharyya, Subir and Bhatt, Nilay and Stalin, C. S. and Agrawal, V. K.},
	month = mar,
	year = {2021},
	note = {arXiv:2101.11540 [astro-ph]},
	keywords = {Astrophysics - High Energy Astrophysical Phenomena},
	pages = {446--457},
	file = {Gulati et al. - 2021 - Multiwavelength monitoring of NGC 1275 over a deca.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/DK4DAKP6/Gulati et al. - 2021 - Multiwavelength monitoring of NGC 1275 over a deca.pdf:application/pdf},
}

@article{reynolds_probing_2021,
	title = {Probing the circumnuclear environment of {NGC1275} with {High}-{Resolution} {X}-ray spectroscopy},
	volume = {507},
	issn = {0035-8711, 1365-2966},
	url = {http://arxiv.org/abs/2108.04276},
	doi = {10.1093/mnras/stab2507},
	abstract = {NGC 1275 is the Brightest Cluster Galaxy (BCG) in the Perseus cluster and hosts the active galactic nucleus (AGN) that is heating the central 100 kpc of the intracluster medium (ICM) atmosphere via a regulated feedback loop. Here we use a deep (490 ks) Cycle-19 Chandra High-Energy Transmission Grating (HETG) observation of NGC 1275 to study the anatomy of this AGN. The X-ray continuum is adequately described by an unabsorbed power-law with photon index $\Gamma$ ? 1.9, creating strong tension with the detected column of molecular gas seen via HCN and HCO+ line absorption against the parsec-scale core/jet. This tension is resolved if we permit a composite X-ray source; allowing a column of ???? \~{} 8 {\texttimes} 1022 cm-2 to cover \~{} 15\% of the X-ray emitter does produce a significant improvement in the statistical quality of the spectral fit. We suggest that the dominant unabsorbed component corresponds to the accretion disk corona, and the sub-dominant X-ray component is the jet working surface and/or jet cocoon that is expanding into clumpy molecular gas. We suggest that this may be a common occurence in BCG-AGN. We conduct a search for photoionized absorbers/winds and fail to detect such a component, ruling out columns and ionization parameters often seen in many other Seyfert galaxies. We detect the 6.4 keV iron-K?? fluorescence line seen previously by XMM-Newton and Hitomi. We describe an analysis methodology which combines dispersive HETG spectra, non-dispersive microcalorimeter spectra, and sensitive XMM-Newton/EPIC spectra in order to constrain (sub)arcsec-scale extensions of the iron-K?? emission region.},
	language = {en},
	number = {4},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Reynolds, Christopher S. and Smith, Robyn N. and Fabian, Andrew C. and Fukazawa, Yasushi and Kara, Erin A. and Mushotzky, Richard F. and Noda, Hirofumi and Tombesi, Francesco and Veilleux, Sylvain},
	month = sep,
	year = {2021},
	note = {arXiv:2108.04276 [astro-ph]},
	keywords = {Astrophysics - High Energy Astrophysical Phenomena},
	pages = {5613--5624},
	file = {Reynolds et al. - 2021 - Probing the circumnuclear environment of NGC1275 w.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/W2M6ZKML/Reynolds et al. - 2021 - Probing the circumnuclear environment of NGC1275 w.pdf:application/pdf},
}

@article{zhang_bubble-driven_2022,
	title = {Bubble-driven {Gas} {Uplift} in {Galaxy} {Clusters} and its {Velocity} {Features}},
	volume = {517},
	issn = {0035-8711, 1365-2966},
	url = {http://arxiv.org/abs/2203.04259},
	doi = {10.1093/mnras/stac2282},
	abstract = {Buoyant bubbles of relativistic plasma are essential for active galactic nucleus feedback in galaxy clusters, stirring and heating the intracluster medium (ICM). Observations suggest that these rising bubbles maintain their integrity and sharp edges much longer than predicted by hydrodynamic simulations. In this study, we assume that bubbles can be modeled as rigid bodies and demonstrate that intact bubbles and their long-term interactions with the ambient ICM play an important role in shaping gas kinematics, forming thin gaseous structures (e.g., H$\alpha$ filaments), and generating internal waves in cluster cores. We find that well-developed eddies are formed in the wake of a buoyantly rising bubble, and it is these eddies, rather than the Darwin drift, that are responsible for most of the gas mass uplift. The eddies gradually elongate along the bubble{\textquoteright}s direction of motion due to the strong density stratification of the atmosphere and eventually detach from the bubble, quickly evolving into a high-speed jet-like stream propagating towards the cluster center. This picture naturally explains the presence of long straight and horseshoe-shaped H$\alpha$ filaments in the Perseus cluster, inward and outward motions of the gas, and the X-ray-weighted gas velocity distributions near the northwestern bubble observed by Hitomi. Our model reproduces the observed H$\alpha$ velocity structure function of filaments, providing a simple interpretation for its steep scaling and normalization: laminar gas flows and large eddies within filaments driven by the intact bubbles, rather than spatially homogeneous small-scale turbulence, are sufficient to produce a structure function consistent with observations.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Zhang, Congyao and Zhuravleva, Irina and Gendron-Marsolais, Marie-Lou and Churazov, Eugene and Schekochihin, Alexander A. and Forman, William R.},
	month = oct,
	year = {2022},
	note = {arXiv:2203.04259 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena},
	pages = {616--631},
	file = {Zhang et al. - 2022 - Bubble-driven Gas Uplift in Galaxy Clusters and it.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/H27EHM3R/Zhang et al. - 2022 - Bubble-driven Gas Uplift in Galaxy Clusters and it.pdf:application/pdf},
}

@article{fabian_relationship_2003,
	title = {The relationship between the optical {Halpha} filaments and the {X}-ray emission in the core of the {Perseus} cluster},
	volume = {344},
	issn = {0035-8711, 1365-2966},
	url = {http://arxiv.org/abs/astro-ph/0306039},
	doi = {10.1046/j.1365-8711.2003.06856.x},
	abstract = {NGC 1275 in the centre of the Perseus cluster of galaxies, Abell 426, is surrounded by a spectacular filamentary H$\alpha$ nebula. Deep Chandra X-ray imaging has revealed that the brighter outer filaments are also detected in soft X-rays. This can be due to conduction and mixing of the cold gas in the filaments with the hot, dense intracluster medium. We show the correspondence of the filaments in both wavebands and draw attention to the relationship of two prominent curved NW filaments to an outer, buoyant radio bubble seen as a hole in the X-ray image. There is a strong resemblance in the shape of the hole and the disposition of the filaments to the behaviour of a large air bubble rising in water. If this is a correct analogy, then the flow is laminar and the intracluster gas around this radio source is not turbulent. We obtain a limit on the viscosity of this gas.},
	language = {en},
	number = {3},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Fabian, A. C. and Sanders, J. S. and Crawford, C. S. and Conselice, C. J. and Gallagher III, J. S. and Wyse, R. F. G.},
	month = sep,
	year = {2003},
	note = {arXiv:astro-ph/0306039},
	keywords = {Astrophysics},
	pages = {L48--L52},
	file = {Fabian et al. - 2003 - The relationship between the optical Halpha filame.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/EX33CV98/Fabian et al. - 2003 - The relationship between the optical Halpha filame.pdf:application/pdf},
}

@article{vantyghem_massive_2021,
	title = {A {Massive}, {Clumpy} {Molecular} {Gas} {Distribution} and {Displaced} {AGN} in {Zw} 3146},
	volume = {910},
	issn = {0004-637X, 1538-4357},
	url = {http://arxiv.org/abs/2102.02300},
	doi = {10.3847/1538-4357/abe306},
	abstract = {We present a recent ALMA observation of the CO(1-0) line emission in the central galaxy of the Zw 3146 galaxy cluster (z = 0.2906). We also present updated X-ray cavity measurements from archival Chandra observations. The 5 {\texttimes} 1010 M supply of molecular gas, which is confined to the central 4 kpc, is marginally resolved into three extensions that are reminiscent of the filaments observed in similar systems. No velocity structure that would be indicative of ordered motion is observed. The three molecular extensions all trail X-ray cavities, and are potentially formed from the condensation of intracluster gas lifted in the wakes of the rising bubbles. Many cycles of feedback would be require to account for the entire molecular gas reservoir. The molecular gas and continuum source are mutually offset by 2.6 kpc, with no detected line emission coincident with the continuum source. It is the molecular gas, not the continuum source, that lies at the gravitational center of the brightest cluster galaxy. As the brightest cluster galaxy contains possible tidal features, the displaced continuum source may correspond to the nucleus of a merging galaxy. We also discuss the possibility that a gravitational wave recoil following a black hole merger may account for the displacement.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Vantyghem, A. N. and McNamara, B. R. and O'Dea, C. P. and Baum, S. A. and Combes, F. and Edge, A. C. and Fabian, A. C. and McDonald, M. and Nulsen, P. E. J. and Russell, H. R. and Salome, P.},
	month = mar,
	year = {2021},
	note = {arXiv:2102.02300 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {53},
	file = {Vantyghem et al. - 2021 - A Massive, Clumpy Molecular Gas Distribution and D.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/4RE7FFEE/Vantyghem et al. - 2021 - A Massive, Clumpy Molecular Gas Distribution and D.pdf:application/pdf},
}

@article{mcnamara_mechanism_2016,
	title = {A {Mechanism} for {Stimulating} {AGN} {Feedback} by {Lifting} {Gas} in {Massive} {Galaxies}},
	volume = {830},
	issn = {0004-637X, 1538-4357},
	url = {http://arxiv.org/abs/1604.04629},
	doi = {10.3847/0004-637X/830/2/79},
	abstract = {Observation shows that nebular emission, molecular gas, and young stars in giant galaxies are associated with rising X-ray bubbles inflated by radio jets launched from nuclear black holes. We propose a model where molecular clouds condense from low entropy gas caught in the updraft of rising X-ray bubbles. The low entropy gas becomes thermally unstable when it is lifted to an altitude where its cooling time is shorter than the time required to fall to its equilibrium location in the galaxy i.e., tc/tI 1. The infall speed of a cloud is bounded by the lesser of its free-fall and terminal speeds, so that the infall time here can exceed the the free-fall time by a significant factor. This mechanism is motivated by ALMA observations revealing molecular clouds lying in the wakes of rising X-ray bubbles with velocities well below their free-fall speeds. Our mechanism would provide cold gas needed to fuel a feedback loop while stabilizing the atmosphere on larger scales. The observed cooling time threshold of \~{} 5 {\texttimes} 108 yr {\textemdash} the clear-cut signature of thermal instability and the onset of nebular emission and star formation{\textemdash} may result from the limited ability of radio bubbles to lift low entropy gas to altitudes where thermal instabilities can ensue. Outflowing molecular clouds are unlikely to escape, but instead return to the central galaxy in a circulating flow. We contrast our mechanism to precipitation models where the minimum value of tc/tff 10 triggers thermal instability, which we find to be inconsistent with observation.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {McNamara, B. R. and Russell, H. R. and Nulsen, P. E. J. and Hogan, M. T. and Fabian, A. C. and Pulido, F. and Edge, A. C.},
	month = oct,
	year = {2016},
	note = {arXiv:1604.04629 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {79},
	file = {McNamara et al. - 2016 - A Mechanism for Stimulating AGN Feedback by Liftin.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/3UZM3LRP/McNamara et al. - 2016 - A Mechanism for Stimulating AGN Feedback by Liftin.pdf:application/pdf},
}

@article{mcdonald_anatomy_2019,
	title = {Anatomy of a {Cooling} {Flow}: {The} {Feedback} {Response} to {Pure} {Cooling} in the {Core} of the {Phoenix} {Cluster}},
	volume = {885},
	issn = {0004-637X, 1538-4357},
	shorttitle = {Anatomy of a {Cooling} {Flow}},
	url = {http://arxiv.org/abs/1904.08942},
	doi = {10.3847/1538-4357/ab464c},
	abstract = {We present new, deep observations of the Phoenix cluster from the Chandra X-ray Observatory, the Hubble Space Telescope, and the Karl Jansky Very Large Array. These data provide an order of magnitude improvement in depth and/or angular resolution at X-ray, optical, and radio wavelengths, yielding an unprecedented view of the core of the Phoenix cluster. We find that the one-dimensional temperature and entropy profiles are consistent with expectations for pure-cooling hydrodynamic simulations and analytic descriptions of homogeneous, steady-state cooling flow models. In particular, the entropy profile is well-fit by a single power law at all radii, with no evidence for excess entropy in the core. In the inner \~{}10 kpc, the cooling time is shorter by an order of magnitude than any other known cluster, while the ratio of the cooling time to freefall time (tcool/tff ) approaches unity, signaling that the ICM is unable to resist multiphase condensation on kpc scales. When we consider the thermodynamic profiles in two dimensions, we find that the cooling is highly asymmetric. The bulk of the cooling in the inner \~{}20 kpc is confined to a low-entropy filament extending northward from the central galaxy, with tcool/tff \~{} 1 over the length of the filament. This northern filament is significantly absorbed, suggesting the presence of \~{}1010 M in cool gas that is absorbing soft X-rays. We detect a substantial reservoir of cool (\~{}104 K) gas (as traced by the [O ii]$\lambda$$\lambda$3726,3729 doublet), which is coincident with the low-entropy filament. The bulk of this cool gas is draped around and behind a pair of X-ray cavities, presumably bubbles that have been inflated by radio jets, which are detected for the first time on kpc scales. These data support a picture in which AGN feedback is promoting the formation of a multiphase medium via a combination of ordered buoyant uplift and locally enhanced turbulence. These processes ought to counteract the tendency for buoyancy to suppress condensation, leading to rapid cooling along the jet axis. The recent mechanical outburst has sufficient energy to offset cooling, and appears to be coupling to the ICM via a cocoon shock, raising the entropy in the direction orthogonal to the radio jets.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {McDonald, M. and McNamara, B. R. and Voit, G. M. and Bayliss, M. and Benson, B. A. and Brodwin, M. and Canning, R. E. A. and Florian, M. K. and Garmire, G. P. and Gaspari, M. and Gladders, M. D. and Hlavacek-Larrondo, J. and Kara, E. and Reichardt, C. L. and Russell, H. R. and Saro, A. and Sharon, K. and Somboonpanyakul, T. and Tremblay, G. R. and van Weeren, R. J.},
	month = nov,
	year = {2019},
	note = {arXiv:1904.08942 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {63},
	file = {McDonald et al. - 2019 - Anatomy of a Cooling Flow The Feedback Response t.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/JCMTA249/McDonald et al. - 2019 - Anatomy of a Cooling Flow The Feedback Response t.pdf:application/pdf},
}

@article{hitomi_collaboration_atmospheric_2018,
	title = {Atmospheric gas dynamics in the {Perseus} cluster observed with {Hitomi}},
	volume = {70},
	issn = {0004-6264, 2053-051X},
	url = {http://arxiv.org/abs/1711.00240},
	doi = {10.1093/pasj/psx138},
	abstract = {Extending the earlier measurements reported in Hitomi collaboration (2016, Nature, 535, 117), we examine the atmospheric gas motions within the central 100{\textasciitilde}kpc of the Perseus cluster using observations obtained with the Hitomi satellite. After correcting for the point spread function of the telescope and using optically thin emission lines, we find that the line-of-sight velocity dispersion of the hot gas is remarkably low and mostly uniform. The velocity dispersion reaches maxima of approximately 200{\textasciitilde}km{\textasciitilde}s\${\textasciicircum}\{-1\}\$ toward the central active galactic nucleus (AGN) and toward the AGN inflated north-western `ghost' bubble. Elsewhere within the observed region, the velocity dispersion appears constant around 100{\textasciitilde}km{\textasciitilde}s\${\textasciicircum}\{-1\}\$. We also detect a velocity gradient with a 100{\textasciitilde}km{\textasciitilde}s\${\textasciicircum}\{-1\}\$ amplitude across the cluster core, consistent with large-scale sloshing of the core gas. If the observed gas motions are isotropic, the kinetic pressure support is less than 10{\textbackslash}\% of the thermal pressure support in the cluster core. The well-resolved optically thin emission lines have Gaussian shapes, indicating that the turbulent driving scale is likely below 100{\textasciitilde}kpc, which is consistent with the size of the AGN jet inflated bubbles. We also report the first measurement of the ion temperature in the intracluster medium, which we find to be consistent with the electron temperature. In addition, we present a new measurement of the redshift to the brightest cluster galaxy NGC{\textasciitilde}1275.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {Publications of the Astronomical Society of Japan},
	author = {Hitomi Collaboration and Aharonian, Felix and Akamatsu, Hiroki and Akimoto, Fumie and Allen, Steven W. and Angelini, Lorella and Audard, Marc and Awaki, Hisamitsu and Axelsson, Magnus and Bamba, Aya and Bautz, Marshall W. and Blandford, Roger and Brenneman, Laura W. and Brown, Gregory V. and Bulbul, Esra and Cackett, Edward M. and Canning, Rebecca E. A. and Chernyakova, Maria and Chiao, Meng P. and Coppi, Paolo S. and Costantini, Elisa and de Plaa, Jelle and de Vries, Cor P. and Herder, Jan-Willem den and Done, Chris and Dotani, Tadayasu and Ebisawa, Ken and Eckart, Megan E. and Enoto, Teruaki and Ezoe, Yuichiro and Fabian, Andrew C. and Ferrigno, Carlo and Foster, Adam R. and Fujimoto, Ryuichi and Fukazawa, Yasushi and Furuzawa, Akihiro and Galeazzi, Massimiliano and Gallo, Luigi C. and Gandhi, Poshak and Giustini, Margherita and Goldwurm, Andrea and Gu, Liyi and Guainazzi, Matteo and Haba, Yoshito and Hagino, Kouichi and Hamaguchi, Kenji and Harrus, Ilana M. and Hatsukade, Isamu and Hayashi, Katsuhiro and Hayashi, Takayuki and Hayashi, Tasuku and Hayashida, Kiyoshi and Hiraga, Junko S. and Hornschemeier, Ann and Hoshino, Akio and Hughes, John P. and Ichinohe, Yuto and Iizuka, Ryo and Inoue, Hajime and Inoue, Shota and Inoue, Yoshiyuki and Ishida, Manabu and Ishikawa, Kumi and Ishisaki, Yoshitaka and Iwai, Masachika and Kaastra, Jelle and Kallman, Tim and Kamae, Tsuneyoshi and Kataoka, Jun and Katsuda, Satoru and Kawai, Nobuyuki and Kelley, Richard L. and Kilbourne, Caroline A. and Kitaguchi, Takao and Kitamoto, Shunji and Kitayama, Tetsu and Kohmura, Takayoshi and Kokubun, Motohide and Koyama, Katsuji and Koyama, Shu and Kretschmar, Peter and Krimm, Hans A. and Kubota, Aya and Kunieda, Hideyo and Laurent, Philippe and Lee, Shiu-Hang and Leutenegger, Maurice A. and Limousin, Olivier and Loewenstein, Michael and Long, Knox S. and Lumb, David and Madejski, Greg and Maeda, Yoshitomo and Maier, Daniel and Makishima, Kazuo and Markevitch, Maxim and Matsumoto, Hironori and Matsushita, Kyoko and McCammon, Dan and McNamara, Brian R. and Mehdipour, Missagh and Miller, Eric D. and Miller, Jon M. and Mineshige, Shin and Mitsuda, Kazuhisa and Mitsuishi, Ikuyuki and Miyazawa, Takuya and Mizuno, Tsunefumi and Mori, Hideyuki and Mori, Koji and Mukai, Koji and Murakami, Hiroshi and Mushotzky, Richard F. and Nakagawa, Takao and Nakajima, Hiroshi and Nakamori, Takeshi and Nakashima, Shinya and Nakazawa, Kazuhiro and Nobukawa, Kumiko K. and Nobukawa, Masayoshi and Noda, Hirofumi and Odaka, Hirokazu and Ohashi, Takaya and Ohno, Masanori and Okajima, Takashi and Ota, Naomi and Ozaki, Masanobu and Paerels, Frits and Paltani, St{\'e}phane and Petre, Robert and Pinto, Ciro and Porter, Frederick S. and Pottschmidt, Katja and Reynolds, Christopher S. and Safi-Harb, Samar and Saito, Shinya and Sakai, Kazuhiro and Sasaki, Toru and Sato, Goro and Sato, Kosuke and Sato, Rie and Sawada, Makoto and Schartel, Norbert and Serlemtsos, Peter J. and Seta, Hiromi and Shidatsu, Megumi and Simionescu, Aurora and Smith, Randall K. and Soong, Yang and Stawarz, {\L }ukasz and Sugawara, Yasuharu and Sugita, Satoshi and Szymkowiak, Andrew and Tajima, Hiroyasu and Takahashi, Hiromitsu and Takahashi, Tadayuki and Takeda, Shin'ichiro and Takei, Yoh and Tamagawa, Toru and Tamura, Takayuki and Tanaka, Keigo and Tanaka, Takaaki and Tanaka, Yasuo and Tanaka, Yasuyuki T. and Tashiro, Makoto S. and Tawara, Yuzuru and Terada, Yukikatsu and Terashima, Yuichi and Tombesi, Francesco and Tomida, Hiroshi and Tsuboi, Yohko and Tsujimoto, Masahiro and Tsunemi, Hiroshi and Tsuru, Takeshi Go and Uchida, Hiroyuki and Uchiyama, Hideki and Uchiyama, Yasunobu and Ueda, Shutaro and Ueda, Yoshihiro and Uno, Shin'ichiro and Urry, C. Megan and Ursino, Eugenio and Wang, Qian H. S. and Watanabe, Shin and Werner, Norbert and Wilkins, Dan R. and Williams, Brian J. and Yamada, Shinya and Yamaguchi, Hiroya and Yamaoka, Kazutaka and Yamasaki, Noriko Y. and Yamauchi, Makoto and Yamauchi, Shigeo and Yaqoob, Tahir and Yatsu, Yoichi and Yonetoku, Daisuke and Zhuravleva, Irina and Zoghbi, Abderahmen},
	month = mar,
	year = {2018},
	note = {arXiv:1711.00240 [astro-ph]},
	keywords = {Astrophysics - High Energy Astrophysical Phenomena},
	pages = {9},
	file = {Hitomi Collaboration et al. - 2018 - Atmospheric gas dynamics in the Perseus cluster ob.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/6Q98V2V7/Hitomi Collaboration et al. - 2018 - Atmospheric gas dynamics in the Perseus cluster ob.pdf:application/pdf},
}

@article{salome_very_2011-1,
	title = {A very extended molecular web around {NGC} 1275},
	volume = {531},
	issn = {0004-6361, 1432-0746},
	url = {http://www.aanda.org/10.1051/0004-6361/200811333},
	doi = {10.1051/0004-6361/200811333},
	abstract = {We present the first detection of CO emission lines in the H$\alpha$ filaments at distances as far as 50 kpc from the centre of the galaxy NGC 1275. This gas is probably dense (>=103 cm-3). However, it is not possible to accurately determine the density and the kinetic temperature of this relatively warm gas (Tkin \~{} 20{\textendash}500 K) with the current data alone. The amount of molecular gas in the filaments is large {\textendash} 109 M (assuming a Galactic N(H2)/ICO ratio). This is 10\% of the total mass of molecular gas detected in this cD galaxy. This gas has large-scale velocities comparable to those seen in H$\alpha$. The origin of the filaments is still unclear, but their formation is very likely linked to the AGN positive feedback that regulates the cooling of the surrounding X-ray-emitting gas as suggested by numerical simulations. We also present high-resolution spectra of the galaxy core. The spatial characteristics of the double-peaked profile suggest that the molecular web of filaments and streamers penetrates down to radii of less than 2 kpc from the central AGN and eventually feeds the galaxy nucleus. The mass of gas inside the very central region is \~{}109 M , and is similar to the mass of molecular gas found in the filaments.},
	language = {en},
	urldate = {2024-05-26},
	journal = {Astronomy \& Astrophysics},
	author = {Salom{\'e}, P. and Combes, F. and Revaz, Y. and Downes, D. and Edge, A. C. and Fabian, A. C.},
	month = jul,
	year = {2011},
	pages = {A85},
	file = {Salom{\'e} et al. - 2011 - A very extended molecular web around NGC 1275.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/KNQMSEG2/Salom{\'e} et al. - 2011 - A very extended molecular web around NGC 1275.pdf:application/pdf},
}

@article{osullivan_building_2019,
	title = {Building a cluster: shocks, cavities, and cooling filaments in the group-group merger {NGC} 6338},
	volume = {488},
	issn = {0035-8711, 1365-2966},
	shorttitle = {Building a cluster},
	url = {http://arxiv.org/abs/1906.07710},
	doi = {10.1093/mnras/stz1711},
	abstract = {We present deep Chandra, XMM-Newton, Giant Metrewave Radio Telescope and H$\alpha$ observations of the group-group merger NGC 6338. X-ray imaging and spectral mapping show that as well as trailing tails of cool, enriched gas, the two cool cores are embedded in an extensive region of shock heated gas with temperatures rising to \~{}5 keV. The velocity distribution of the member galaxies show that the merger is occurring primarily along the line of sight, and we estimate that the collision has produced shocks of Mach number M=2.3 or greater, making this one of the most violent mergers yet observed between galaxy groups. Both cool cores host potential AGN cavities and H$\alpha$ nebulae, indicating rapid radiative cooling. In the southern cool core around NGC 6338, we find that the X-ray filaments associated with the H$\alpha$ nebula have low entropies ({\textless}10 keV cm2) and short cooling times (\~{}200-300 Myr). In the northern core we identify an H$\alpha$ cloud associated with a bar of dense, cool X-ray gas offset from the dominant galaxy. We find no evidence of current jet activity in either core. We estimate the total mass of the system and find that the product of this group-group merger will likely be a galaxy cluster.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {O'Sullivan, Ewan and Schellenberger, Gerrit and Burke, D. J. and Sun, Ming and Vrtilek, Jan M. and David, Laurence P. and Sarazin, Craig},
	month = sep,
	year = {2019},
	note = {arXiv:1906.07710 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena},
	pages = {2925--2946},
	file = {O'Sullivan et al. - 2019 - Building a cluster shocks, cavities, and cooling .pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/3RDHKZB6/O'Sullivan et al. - 2019 - Building a cluster shocks, cavities, and cooling .pdf:application/pdf},
}

@article{salome_cold_2006,
	title = {Cold molecular gas in the {Perseus} cluster core: {Association} with {X}-ray cavity, {H} \textit{$\alpha$} filaments and cooling flow},
	volume = {454},
	issn = {0004-6361, 1432-0746},
	shorttitle = {Cold molecular gas in the {Perseus} cluster core},
	url = {http://www.aanda.org/10.1051/0004-6361:20054745},
	doi = {10.1051/0004-6361:20054745},
	abstract = {Cold molecular gas has recently been detected in several cooling flow clusters of galaxies containing huge optical nebula. These optical filaments are tightly linked to cooling flows and related phenomena, such as rising bubbles of relativistic plasma fed by radio jets. We present here a map, in the CO(2{\textendash}1) rotational line, of the cold molecular gas associated with some of the H$\alpha$ filaments surrounding the central galaxy of the Perseus cluster: NGC 1275. The map, extending to about 50 kpc (135 arcsec) from the center of the galaxy, has been made with the 18-receiver array HERA at the focus of the IRAM 30 m telescope. Although most of the cold gas is concentrated to the center of the galaxy, the CO emission is also clearly associated with the extended filaments conspicuous in ionised gas, and could trace a possible reservoir fueling the star formation there. Some of the CO emission is also found where the X-ray gas could cool down more efficiently at the rims of the central X-ray cavities (where the hot gas is thought to have been pushed out and compressed by the expanding radio lobes of the central AGN). The CO global kinematics do not show any rotation in NGC 1275. The cold gas is probably a mixture of gas falling down on the central galaxy and of uplifted gas dragged out by a rising bubble in the intracluster medium. As recently suggested in other cluster cores, the cold gas peculiar morphology and kinematics argue for the picture of an intermittent cooling flow scenario where the central AGN plays an important role.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {Astronomy \& Astrophysics},
	author = {Salom{\'e}, P. and Combes, F. and Edge, A. C. and Crawford, C. and Erlund, M. and Fabian, A. C. and Hatch, N. A. and Johnstone, R. M. and Sanders, J. S. and Wilman, R. J.},
	month = aug,
	year = {2006},
	pages = {437--445},
	file = {Salom{\'e} et al. - 2006 - Cold molecular gas in the Perseus cluster core As.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/PBMEU5E8/Salom{\'e} et al. - 2006 - Cold molecular gas in the Perseus cluster core As.pdf:application/pdf},
}

@article{russell_driving_2019-1,
	title = {Driving massive molecular gas flows in central cluster galaxies with {AGN} feedback},
	volume = {490},
	issn = {0035-8711, 1365-2966},
	url = {http://arxiv.org/abs/1902.09227},
	doi = {10.1093/mnras/stz2719},
	abstract = {We present an analysis of new and archival ALMA observations of molecular gas in twelve central cluster galaxies. We examine emerging trends in molecular filament morphology and gas velocities to understand their origins. Molecular gas masses in these systems span 109 - 1011 M , far more than most gas-rich galaxies. ALMA images reveal a distribution of morphologies from filamentary to disk-dominated structures. Circumnuclear disks on kiloparsec scales appear rare. In most systems, half to nearly all of the molecular gas lies in filamentary structures with masses of a few {\texttimes}108-10 M that extend radially several to several tens of kpc. In nearly all cases the molecular gas velocities lie far below stellar velocity dispersions, indicating youth, transience or both. Filament bulk velocities lie far below the galaxy{\textquoteright}s escape and free-fall speeds indicating they are bound and being decelerated. Most extended molecular filaments surround or lie beneath radio bubbles inflated by the central AGN. Smooth velocity gradients found along the filaments are consistent with gas flowing along streamlines surrounding these bubbles. Evidence suggests most of the molecular clouds formed from low entropy X-ray gas that became thermally unstable and cooled when lifted by the buoyant bubbles. Uplifted gas will stall and fall back to the galaxy in a circulating flow. The distribution in morphologies from filament to disk-dominated sources therefore implies slowly evolving molecular structures driven by the episodic activity of the AGN.},
	language = {en},
	number = {3},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Russell, H. R. and McNamara, B. R. and Fabian, A. C. and Nulsen, P. E. J. and Combes, F. and Edge, A. C. and Madar, M. and Olivares, V. and Salome, P. and Vantyghem, A. N.},
	month = dec,
	year = {2019},
	note = {arXiv:1902.09227 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena},
	pages = {3025--3045},
	file = {Russell et al. - 2019 - Driving massive molecular gas flows in central clu.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/6CIFU2PA/Russell et al. - 2019 - Driving massive molecular gas flows in central clu.pdf:application/pdf},
}

@article{polles_excitation_2019,
	title = {Excitation mechanisms in the intracluster filaments surrounding {Brightest} {Cluster} {Galaxies}},
	volume = {15},
	issn = {1743-9213, 1743-9221},
	url = {http://arxiv.org/abs/2103.09842},
	doi = {10.1017/S1743921320002343},
	abstract = {Methods. Using the Cloudy code, we model the photoionization and photodissociation of a slab of gas of optical depth AV <=30 mag at constant pressure, in order to calculate self-consistently all of the gas phases, from ionized gas to molecular gas. The ionizing source is the extreme ultraviolet (EUV) and soft X-ray radiation emitted by the cooling gas. We test these models comparing their predictions to the rich multi-wavelength observations, from optical to submillimeter, now achieved in cool core cluster.
Results. Such models of self-irradiated clouds, when reaching large enough AV, lead to a cloud structure with ionized, atomic and molecular gas phases. These models reproduce most of the multi-wavelength spectra observed in the nebulae surrounding the BCGs, not only the LINER-like optical diagnostics: [O iii]$\lambda$ 5007 {\r A}/H$\beta$, [N ii]$\lambda$ 6583 {\r A}/H$\alpha$ and ([S ii]$\lambda$ 6716 {\r A}+[S ii]$\lambda$ 6731 {\r A})/H$\alpha$ but also the infrared emission lines from the atomic gas. [O i]$\lambda$ 6300 {\r A}/H$\alpha$, instead, is overestimated across the full parameter space, except for very low AV. The modeled ro-vib H2 lines also match observations, which indicates that near and mid-IR H2 lines are mostly excited by collisions between H2 molecules and secondary electrons produced naturally inside the cloud by the interaction between the X-rays and the cold gas in the filament. However, there is still some tension between ionized and molecular line tracers (i.e. CO), which requires to optimize the cloud structure and the density of the molecular zone. The limited range of parameters over which predictions match observations allows us to constrain, in spite of degeneracies in the parameter space, the intensity of X-ray radiation bathing filaments, as well as some of their physical properties like AV or the level of turbulent heating rate.
Conclusions. The reprocessing of the EUV and X-ray radiation from the plasma cooling is an important powering source of line emission from filaments surrounding BCGs. Cloudy self-irradiated X-ray excitation models, coupled with a small level of turbulent heating, manage to reproduce simultaneously a large number of optical-to-infrared line ratios when all the gas phases (from ionized to molecular) are modelled self-consistently. Releasing some of the simplifications of our model, like the constant pressure, or adding the radiation fields from the AGN and stars, as well as a combination of matter- and radiation-bounded cloud distribution, should improve the predictions of line emission from the different gas phases.},
	language = {en},
	number = {S359},
	urldate = {2024-05-26},
	journal = {Proceedings of the International Astronomical Union},
	author = {Polles, F. L. and Salom{\'e}, P. and Guillard, P. and Godard, B. and For{\^e}ts, G. Pineau des and Olivares, V. and Beckmann, R. S. and Canning, R. E. A. and Combes, F. and Dubois, Y. and Edge, A. C. and Fabian, A. C. and Ferland, G. J. and Hamer, S. L. and Lehnert, M. D.},
	month = mar,
	year = {2019},
	note = {arXiv:2103.09842 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {185--187},
	file = {Polles et al. - 2019 - Excitation mechanisms in the intracluster filament.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/ZU3FA3IM/Polles et al. - 2019 - Excitation mechanisms in the intracluster filament.pdf:application/pdf},
}

@article{baum_extended_1989,
	title = {Extended optical line emitting gas in powerful radio galaxies - {What} is the radio emission-line connection?},
	volume = {336},
	issn = {0004-637X, 1538-4357},
	url = {http://adsabs.harvard.edu/doi/10.1086/167044},
	doi = {10.1086/167044},
	language = {en},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Baum, Stefi A. and Heckman, Timothy},
	month = jan,
	year = {1989},
	pages = {702},
	file = {Baum and Heckman - 1989 - Extended optical line emitting gas in powerful rad.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/R3SM74TG/Baum and Heckman - 1989 - Extended optical line emitting gas in powerful rad.pdf:application/pdf},
}

@article{kravtsov_formation_2012,
	title = {Formation of {Galaxy} {Clusters}},
	volume = {50},
	issn = {0066-4146, 1545-4282},
	url = {https://www.annualreviews.org/doi/10.1146/annurev-astro-081811-125502},
	doi = {10.1146/annurev-astro-081811-125502},
	abstract = {Formation of galaxy clusters corresponds to the collapse of the largest gravitationally bound overdensities in the initial density field and is accompanied by the most energetic phenomena since the Big Bang and by the complex interplay between gravity-induced dynamics of collapse and baryonic processes associated with galaxy formation. Galaxy clusters are, thus, at the cross-roads of cosmology and astrophysics and are unique laboratories for testing models of gravitational structure formation, galaxy evolution, thermodynamics of the intergalactic medium, and plasma physics. At the same time, their large masses make them a useful probe of growth of structure over cosmological time, thus providing cosmological constraints that are complementary to other probes. In this review, we describe our current understanding of cluster formation: from the general picture of collapse from initial density fluctuations in an expanding Universe to detailed simulations of cluster formation including the effects of galaxy formation. We outline both the areas in which highly accurate predictions of theoretical models can be obtained and areas where predictions are uncertain due to uncertain physics of galaxy formation and feedback. The former includes the description of the structural properties of the dark matter halos hosting clusters, their mass function, and clustering properties. Their study provides a foundation for cosmological applications of clusters and for testing the fundamental assumptions of the standard model of structure formation. The latter includes the description of the total gas and stellar fractions and the thermodynamical and nonthermal processes in the intracluster plasma. Their study serves as a testing ground for galaxy formation models and plasma physics. In this context, we identify a suitable radial range where the observed thermal properties of the intracluster plasma exhibit the most regular behavior and, thus, can be used to define robust observational proxies for the total cluster mass. Finally, we discuss the formation of clusters in nonstandard cosmological models, such as non-Gaussian models for the initial density field and models with modified gravity, along with prospects for testing these alternative scenarios with large cluster surveys in the near future.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {Annual Review of Astronomy and Astrophysics},
	author = {Kravtsov, Andrey V. and Borgani, Stefano},
	month = sep,
	year = {2012},
	pages = {353--409},
	file = {Kravtsov and Borgani - 2012 - Formation of Galaxy Clusters.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/Y6YA9P66/Kravtsov and Borgani - 2012 - Formation of Galaxy Clusters.pdf:application/pdf},
}

@article{lim_radially_2008,
	title = {Radially {Inflowing} {Molecular} {Gas} in {NGC} 1275 {Deposited} by an {X}-{Ray} {Cooling} {Flow} in the {Perseus} {Cluster}},
	volume = {672},
	issn = {0004-637X, 1538-4357},
	url = {https://iopscience.iop.org/article/10.1086/523664},
	doi = {10.1086/523664},
	abstract = {We have imaged in CO(2Y1) the molecular gas in NGC 1275 ( Perseus A), the cD galaxy at the center of the Perseus Cluster, at a spatial resolution of \$1 kpc over a central region of radius \$10 kpc. Per A is known to contain \$1:3 ; 1010 M  of molecular gas, which has been proposed to be captured from mergers with or ram pressure stripping of gas-rich galaxies, or accreted from a X-ray cooling flow. The molecular gas detected in our image has a total mass of \$4 ; 109 M , and for the first time can be seen to be concentrated in three radial filaments with lengths ranging from at least 1.1 to 2.4 kpc, all lying in the east-west directions spanning the center of the galaxy to radii of \$8 kpc. The eastern and outer western filaments exhibit larger blueshifted velocities with decreasing radii, whereas the inner western filament spans the systemic velocity of the galaxy. The molecular gas shows no signature of orbital motion, and is therefore unlikely to have been captured from gas-rich galaxies. Instead, we are able to reproduce the observed kinematics of the two outer filaments as free fall in the gravitational potential of Per A, as would be expected if they originate from a X-ray cooling flow. Indeed, all three filaments lie between two prominent X-ray cavities carved out by radio jets from Per A, and closely resemble the spatial distribution of the coolest X-ray gas in the cluster core. The inferred mass deposition rate into the two outermost filaments alone is roughly 75 M  yr{\`A}1. This cooling flow can provide a nearly continuous supply of molecular gas to fuel the active nucleus in Per A.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Lim, Jeremy and Ao, YiPing and {Dinh-V-Trung}},
	month = jan,
	year = {2008},
	pages = {252--265},
	file = {Lim et al. - 2008 - Radially Inflowing Molecular Gas in NGC 1275 Depos.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/XX29TUHH/Lim et al. - 2008 - Radially Inflowing Molecular Gas in NGC 1275 Depos.pdf:application/pdf},
}

@article{lim_molecular_2012,
	title = {A {MOLECULAR} {HYDROGEN} {NEBULA} {IN} {THE} {CENTRAL} {cD} {GALAXY} {OF} {THE} {PERSEUS} {CLUSTER}},
	volume = {744},
	issn = {0004-637X, 1538-4357},
	url = {https://iopscience.iop.org/article/10.1088/0004-637X/744/2/112},
	doi = {10.1088/0004-637X/744/2/112},
	abstract = {We report narrowband imaging of the 1{\textendash}0 S(1) ro-vibrational transition of molecular hydrogen (H2) from NGC 1275, the central cD galaxy of the Perseus Cluster. We find that the H2 gas has a spatial morphology identical to the optical emission-line nebula associated with this galaxy, a total luminosity in H2 1{\textendash}0 S(1) only an order of magnitude less than in H$\alpha$, and if the line-emitting gas is thermalized a mass (at \~{}2000 K) that is over two orders of magnitude smaller than that of the optical emission-line nebula (at \~{}10,000 K). The ratio in H2 1{\textendash}0 S(1) to H$\alpha$ + [N ii] line intensities spans a characteristic range of \~{}0.02{\textendash}0.08 throughout the nebula; the brighter inner nebula exhibits patches with (nearly) constant line ratios unrelated to individual filaments. Recent models proposed to explain the peculiar nebular spectrum from the optical to infrared invoke thermalized along with non-thermalized injection of energy from ionizing particles. The energy density of highly relativistic electrons inferred to cause inverse-Compton scattering of hard X-ray emission from the core of the Perseus Cluster decreases steeply beyond a central radius of \~{}20 kpc, yet we do not find any changes in the average or range spanned by the H2 1{\textendash}0 S(1) to H$\alpha$ + [N ii] line ratio between the inner ( 20 kpc) and outer (\~{}20{\textendash}50 kpc) nebulae. On the other hand, saturated conduction from the surrounding X-ray gas produces, in the absence of magnetic fields, a heat flux that is approximately constant throughout the nebula: the change in the line ratio with position would then reflect the ability of the X-ray gas to penetrate presumably magnetically threaded filaments at different locations.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Lim, Jeremy and Ohyama, Youichi and Chi-Hung, Yan and {Dinh-V-Trung} and Shiang-Yu, Wang},
	month = jan,
	year = {2012},
	pages = {112},
	file = {Lim et al. - 2012 - A MOLECULAR HYDROGEN NEBULA IN THE CENTRAL cD GALA.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/B5IJEBFK/Lim et al. - 2012 - A MOLECULAR HYDROGEN NEBULA IN THE CENTRAL cD GALA.pdf:application/pdf},
}

@article{fabian_magnetic_2008,
	title = {Magnetic support of the optical emission line filaments in {NGC} 1275},
	volume = {454},
	copyright = {http://www.springer.com/tdm},
	issn = {0028-0836, 1476-4687},
	url = {https://www.nature.com/articles/nature07169},
	doi = {10.1038/nature07169},
	language = {en},
	number = {7207},
	urldate = {2024-05-26},
	journal = {Nature},
	author = {Fabian, A. C. and Johnstone, R. M. and Sanders, J. S. and Conselice, C. J. and Crawford, C. S. and Iii, J. S. Gallagher and Zweibel, E.},
	month = aug,
	year = {2008},
	pages = {968--970},
	file = {Fabian et al. - 2008 - Magnetic support of the optical emission line fila.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/ESVSRA99/Fabian et al. - 2008 - Magnetic support of the optical emission line fila.pdf:application/pdf},
}

@article{mcdonald_origin_2010,
	title = {{ON} {THE} {ORIGIN} {OF} {THE} {EXTENDED} {H$\alpha$} {FILAMENTS} {IN} {COOLING} {FLOW} {CLUSTERS}},
	volume = {721},
	issn = {0004-637X, 1538-4357},
	url = {https://iopscience.iop.org/article/10.1088/0004-637X/721/2/1262},
	doi = {10.1088/0004-637X/721/2/1262},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {McDonald, Michael and Veilleux, Sylvain and Rupke, David S. N. and Mushotzky, Richard},
	month = oct,
	year = {2010},
	pages = {1262--1283},
	file = {McDonald et al. - 2010 - ON THE ORIGIN OF THE EXTENDED H$\alpha$ FILAMENTS IN COOL.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/ZVHMN2Z8/McDonald et al. - 2010 - ON THE ORIGIN OF THE EXTENDED H$\alpha$ FILAMENTS IN COOL.pdf:application/pdf},
}

@article{mcdonald_optical_2012,
	title = {{OPTICAL} {SPECTROSCOPY} {OF} {H$\alpha$} {FILAMENTS} {IN} {COOL} {CORE} {CLUSTERS}: {KINEMATICS}, {REDDENING}, {AND} {SOURCES} {OF} {IONIZATION}},
	volume = {746},
	issn = {0004-637X, 1538-4357},
	shorttitle = {{OPTICAL} {SPECTROSCOPY} {OF} {H$\alpha$} {FILAMENTS} {IN} {COOL} {CORE} {CLUSTERS}},
	url = {https://iopscience.iop.org/article/10.1088/0004-637X/746/2/153},
	doi = {10.1088/0004-637X/746/2/153},
	abstract = {We have obtained deep, high spatial and spectral resolution, long-slit spectra of the H$\alpha$ nebulae in the cool cores of nine galaxy clusters. This sample provides a wealth of information on the ionization state, kinematics, and reddening of the warm gas in the cool cores of galaxy clusters. We find evidence for only small amounts of reddening in the extended, line-emitting filaments, with the majority of filaments having E(B - V ) {\textless} 0.2. We find, in agreement with previous works, that the optical emission in cool core clusters has elevated low-ionization line ratios. The combination of [O iii]/H$\beta$, [N ii]/H$\alpha$, [S ii]/H$\alpha$, and [O i]/H$\alpha$ allow us to rule out collisional ionization by cosmic rays, thermal conduction, and photoionization by intracluster medium (ICM) X-rays and active galactic nuclei as strong contributors to the ionization in the bulk of the optical line-emitting gas in both the nuclei and filaments. The data are adequately described by a composite model of slow shocks and star formation. This model is further supported by an observed correlation between the line widths and low-ionization line ratios which becomes stronger in systems with more modest star formation activity based on far-ultraviolet observations. We find that the more extended, narrow filaments tend to have shallower velocity gradients and narrower line widths than the compact filamentary complexes. We confirm that the widths of the emission lines decrease with radius, from FWHM \~{} 600 km s-1 in the nuclei to FWHM \~{}100 km s-1 in the most extended filaments. The variation of line width with radius is vastly different than what is measured from stellar absorption lines in a typical giant elliptical galaxy, suggesting that the velocity width of the warm gas may in fact be linked to ICM turbulence and, thus, may provide a glimpse into the amount of turbulence in cool cores. In the central regions (r {\textless} 10 kpc) of several systems the warm gas shows kinematic signatures consistent with rotation, consistent with earlier work. We find that the kinematics of the most extended filaments in this sample are broadly consistent with both infall and outflow, and recommend further studies linking the warm gas kinematics to both radio and X-ray maps in order to further understand the observed kinematics.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {McDonald, Michael and Veilleux, Sylvain and Rupke, David S. N.},
	month = feb,
	year = {2012},
	pages = {153},
	file = {McDonald et al. - 2012 - OPTICAL SPECTROSCOPY OF H$\alpha$ FILAMENTS IN COOL CORE .pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/TH3BF3ZY/McDonald et al. - 2012 - OPTICAL SPECTROSCOPY OF H$\alpha$ FILAMENTS IN COOL CORE .pdf:application/pdf},
}

@article{kewley_host_2006,
	title = {The host galaxies and classification of active galactic nuclei},
	volume = {372},
	issn = {0035-8711, 1365-2966},
	url = {https://academic.oup.com/mnras/article-lookup/doi/10.1111/j.1365-2966.2006.10859.x},
	doi = {10.1111/j.1365-2966.2006.10859.x},
	abstract = {We present an analysis of the host properties of 85 224 emission-line galaxies selected from the Sloan Digital Sky Survey. We show that Seyferts and low-ionization narrow emission-line regions (LINERs) form clearly separated branches on the standard optical diagnostic diagrams. We derive a new empirical classification scheme which cleanly separates star-forming galaxies, composite active galactic nucleus{\textendash}H II (AGN{\textendash}H II) galaxies, Seyferts and LINERs and we study the host galaxy properties of these different classes of objects. LINERs are older, more massive, less dusty, less concentrated, and they have higher velocity dispersions and lower [O III] luminosities than Seyfert galaxies have. Seyferts and LINERs are most strongly distinguished by their [O III] luminosities. We then consider the quantity L[O III]/$\sigma$ 4, which is an indicator of the black hole accretion rate relative to the Eddington rate. Remarkably, we find that at fixed L[O III]/$\sigma$ 4, all differences between Seyfert and LINER host properties disappear. LINERs and Seyferts form a continuous sequence, with LINERs dominant at low L/LEDD and Seyferts dominant at high L/LEDD. These results suggest that the majority of LINERs are AGN and that the Seyfert/LINER dichotomy is analogous to the high/low-state models and show that pure LINERs require a harder ionizing radiation field with lower ionization parameter than required by Seyfert galaxies, consistent with the low and high X-ray binary states.},
	language = {en},
	number = {3},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Kewley, L. J. and Groves, B. and Kauffmann, G. and Heckman, T.},
	month = nov,
	year = {2006},
	pages = {961--976},
	file = {Kewley et al. - 2006 - The host galaxies and classification of active gal.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/FY36KVJ7/Kewley et al. - 2006 - The host galaxies and classification of active gal.pdf:application/pdf},
}

@article{fabian_wide_2011,
	title = {A wide {Chandra} view of the core of the {Perseus} cluster: {A} wider view of the {Perseus} cluster},
	volume = {418},
	issn = {00358711},
	shorttitle = {A wide {Chandra} view of the core of the {Perseus} cluster},
	url = {https://academic.oup.com/mnras/article-lookup/doi/10.1111/j.1365-2966.2011.19402.x},
	doi = {10.1111/j.1365-2966.2011.19402.x},
	abstract = {We present new Chandra images of the X-ray emission from the core of the Perseus cluster of galaxies. The total observation time is now 1.4 Ms. New depressions in X-ray surface brightness are discovered to the north of NGC 1275, which we interpret as old rising bubbles. They imply that bubbles are long-lived and do not readily breakup when rising in the hot cluster atmosphere. The existence of a 300 kpc long NNW{\textendash}SSW bubble axis means there cannot be significant transverse large-scale flows exceeding 100 km s-1. Interesting spatial correlations are seen along that axis in early deep radio maps. A semicircular cold front about 100 kpc west of the nucleus is seen. It separates an inner disturbed region dominated by the activity of the active nucleus of NGC 1275 from the outer region where a subcluster merger dominates.},
	language = {en},
	number = {4},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Fabian, A. C. and Sanders, J. S. and Allen, S. W. and Canning, R. E. A. and Churazov, E. and Crawford, C. S. and Forman, W. and GaBany, J. and Hlavacek-Larrondo, J. and Johnstone, R. M. and Russell, H. R. and Reynolds, C. S. and Salom{\'e}, P. and Taylor, G. B. and Young, A. J.},
	month = dec,
	year = {2011},
	pages = {2154--2164},
	file = {Fabian et al. - 2011 - A wide Chandra view of the core of the Perseus clu.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/Z7834ZXW/Fabian et al. - 2011 - A wide Chandra view of the core of the Perseus clu.pdf:application/pdf},
}

@article{ho_multiple_2009,
	title = {{MULTIPLE} {RADIAL} {COOL} {MOLECULAR} {FILAMENTS} {IN} {NGC} 1275},
	volume = {698},
	issn = {0004-637X, 1538-4357},
	url = {https://iopscience.iop.org/article/10.1088/0004-637X/698/2/1191},
	doi = {10.1088/0004-637X/698/2/1191},
	abstract = {We have extended our previous observation of NGC 1275 (Perseus A (Per A), the central giant elliptical galaxy in the Perseus Cluster) covering a central radius of \~{}10 kpc to the entire main body of cool molecular gas spanning \~{}14 kpc east and west of the center. We find no new features beyond the region previously mapped, and show that all six spatially resolved features on both the eastern and western sides (three on each side) comprise radially aligned filaments. Such radial filaments can be most naturally explained by a model in which gas deposited {\textquotedblleft}upstream{\textquotedblright} in localized regions experiencing a X-ray cooling flow subsequently free falls along the gravitational potential of Per A, as we previously showed can explain the observed kinematics of the two longest filaments. All the detected filaments coincide with locally bright H$\alpha$ features, and have a ratio of CO(2{\textendash}1) to H$\alpha$ luminosity of \~{}10-3; we show that these filaments have lower star formation efficiencies than the nearly constant value found for molecular gas in nearby normal spiral galaxies. On the other hand, some at least equally luminous H$\alpha$ features, including a previously identified giant H ii region, show no detectable cool molecular gas with a corresponding ratio at least a factor of \~{}5 lower; in the giant H ii region, essentially all the preexisting molecular gas may have been converted to stars. We demonstrate that all the cool molecular filaments are gravitationally bound, and without any means of support beyond thermal pressure should collapse on timescales 106 yr. By comparison, as we showed previously, the two longest filaments have much longer dynamical ages of \~{}107 yr. Tidal shear may help delay their collapse, but more likely turbulent velocities of at least a few tens of km s-1 or magnetic fields with strengths of at least several \~{}10 $\mu$G are required to support these filaments.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Ho, I-Ting and Lim, Jeremy and {Dinh-V-Trung}},
	month = jun,
	year = {2009},
	pages = {1191--1206},
	file = {Ho et al. - 2009 - MULTIPLE RADIAL COOL MOLECULAR FILAMENTS IN NGC 12.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/U6XMYY4J/Ho et al. - 2009 - MULTIPLE RADIAL COOL MOLECULAR FILAMENTS IN NGC 12.pdf:application/pdf},
}

@article{nagai_alma_2019,
	title = {The {ALMA} {Discovery} of the {Rotating} {Disk} and {Fast} {Outflow} of {Cold} {Molecular} {Gas} in {NGC} 1275},
	volume = {883},
	issn = {0004-637X, 1538-4357},
	url = {https://iopscience.iop.org/article/10.3847/1538-4357/ab3e6e},
	doi = {10.3847/1538-4357/ab3e6e},
	abstract = {We present observations using the Atacama Large Millimeter/submillimeter Array of the CO(2-1), HCN(3-2), and HCO+(3-2) lines in the nearby radio galaxy/brightest cluster galaxy (BCG) NGC?1275 with a spatial resolution of \~{}20 pc. In previous observations, the CO(2-1) emission was detected as radial filaments lying in the east{\textendash}west direction on a kiloparsec scale. We resolved the inner filament and found that it cannot be represented by a simple infalling stream on a sub-kiloparsec scale. The observed complex nature of the filament resembles the cold gas structure predicted by numerical simulations of cold chaotic accretion. Within the central 100 pc, we detected a rotational disk of molecular gas whose mass is \~{}108 Me. This is the first evidence of the presence of a massive cold gas disk on this spatial scale for BCGs. A crude estimate suggests that the accretion rate of the cold gas can be higher than that of hot gas. The disk rotation axis is approximately consistent with the radio-jet axis. This probably suggests that the cold gas disk is physically connected to the innermost accretion disk, which is responsible for jet launching. We also detected absorption features in the HCN(3-2) and HCO+(3-2) spectra against the radio continuum emission mostly radiated by a jet of size \~{}1.2 pc. The absorption features are blueshifted from the systemic velocity by \~{}300{\textendash}600 km s-1, suggesting the presence of outflowing gas from the active galactic nucleus (AGN). We discuss the relation of the AGN feeding with cold accretion, the origin of blueshifted absorption, and an estimate of the black hole mass using molecular gas dynamics.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Nagai, H. and Onishi, K. and Kawakatu, N. and Fujita, Y. and Kino, M. and Fukazawa, Y. and Lim, J. and Forman, W. and Vrtilek, J. and Nakanishi, K. and Noda, H. and Asada, K. and Wajima, K. and Ohyama, Y. and David, L. and Daikuhara, K.},
	month = oct,
	year = {2019},
	pages = {193},
	file = {Nagai et al. - 2019 - The ALMA Discovery of the Rotating Disk and Fast O.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/RRNB5IG8/Nagai et al. - 2019 - The ALMA Discovery of the Rotating Disk and Fast O.pdf:application/pdf},
}

@article{nagai_diffuse_2021,
	title = {Diffuse {Synchrotron} {Emission} {Associated} with the {Starburst} in the {Circumnuclear} {Disk} of {NGC} 1275},
	volume = {914},
	issn = {2041-8205, 2041-8213},
	url = {https://iopscience.iop.org/article/10.3847/2041-8213/ac03ba},
	doi = {10.3847/2041-8213/ac03ba},
	abstract = {Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations found a positive correlation between the mass of dense molecular gas in the circumnuclear disks (CNDs) and accretion rate to the active galactic nuclei (AGNs). This indicates that star formation activity in the CNDs is essential for triggering the accretion of mass to AGNs. Although the starburst-driven turbulence is a key mechanism for the transfer of angular momentum and the resultant mass accretion from the CND scale to the inner radius, the observational evidence is lacking. We report the very-long-baseline-interferometry detection of the diffuse synchrotron emission on a scale of several tens of parsecs coinciding spatially with the molecular gas disk recently discovered by ALMA observations in NGC 1275. The synchrotron emissions most likely resulted from the relativistic electrons produced by the supernova explosions. This is unambiguous evidence of the star formation activity in a CND. The turbulent velocity and the scale height of the CND predicted from the supernova-driven turbulence model agree with the observations, although the model-predicted accretion rate disagrees with the bolometric luminosity. This might indicate that additional mechanisms to enhance the turbulence are required for the inner disk. We discuss the multiphase nature of the CND by combining the information of the CO emission, synchrotron emission, and free{\textendash}free absorption.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal Letters},
	author = {Nagai, H. and Kawakatu, N.},
	month = jun,
	year = {2021},
	pages = {L11},
	file = {Nagai and Kawakatu - 2021 - Diffuse Synchrotron Emission Associated with the S.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/3D7F4S9D/Nagai and Kawakatu - 2021 - Diffuse Synchrotron Emission Associated with the S.pdf:application/pdf},
}

@article{fabian_magnetic_2008-1,
	title = {Magnetic support of the optical emission line filaments in {NGC} 1275},
	volume = {454},
	copyright = {http://www.springer.com/tdm},
	issn = {0028-0836, 1476-4687},
	url = {https://www.nature.com/articles/nature07169},
	doi = {10.1038/nature07169},
	language = {en},
	number = {7207},
	urldate = {2024-05-26},
	journal = {Nature},
	author = {Fabian, A. C. and Johnstone, R. M. and Sanders, J. S. and Conselice, C. J. and Crawford, C. S. and Iii, J. S. Gallagher and Zweibel, E.},
	month = aug,
	year = {2008},
	pages = {968--970},
	file = {Fabian et al. - 2008 - Magnetic support of the optical emission line fila.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/M2IY4H2R/Fabian et al. - 2008 - Magnetic support of the optical emission line fila.pdf:application/pdf},
}

@article{hatch_origin_2006,
	title = {On the origin and excitation of the extended nebula surrounding {NGC} 1275},
	volume = {367},
	issn = {0035-8711, 1365-2966},
	url = {https://academic.oup.com/mnras/article-lookup/doi/10.1111/j.1365-2966.2006.09970.x},
	doi = {10.1111/j.1365-2966.2006.09970.x},
	abstract = {We use line-of-sight velocity information on the filamentary emission-line nebula of NGC 1275 to infer a dynamical model of the nebula{\textquoteright}s flow through the surrounding intracluster gas. We detect outflowing gas and flow patterns that match simulations of buoyantly rising bubbles from which we deduce that some of the nebula filaments have been drawn out of NGC 1275. We find a radial gradient of the ratio [N II]$\lambda$6584/H$\alpha$ which may be due to a variation in metallicity, interactions with the surrounding intracluster medium or a hardening of the excitation mechanism. We find no preferred spatial correlation of stellar clusters within the filaments and there is a notable lack of [O III]$\lambda$5007 emission, therefore it is unlikely that the filaments are ionized by stellar ultraviolet.},
	language = {en},
	number = {2},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Hatch, N. A. and Crawford, C. S. and Johnstone, R. M. and Fabian, A. C.},
	month = apr,
	year = {2006},
	pages = {433--448},
	file = {Hatch et al. - 2006 - On the origin and excitation of the extended nebul.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/PSJL5I5W/Hatch et al. - 2006 - On the origin and excitation of the extended nebul.pdf:application/pdf},
}

@article{plambeck_probing_2014,
	title = {{PROBING} {THE} {PARSEC}-{SCALE} {ACCRETION} {FLOW} {OF} {3C} 84 {WITH} {MILLIMETER} {WAVELENGTH} {POLARIMETRY}},
	volume = {797},
	copyright = {http://iopscience.iop.org/info/page/text-and-data-mining},
	issn = {1538-4357},
	url = {https://iopscience.iop.org/article/10.1088/0004-637X/797/1/66},
	doi = {10.1088/0004-637X/797/1/66},
	abstract = {We report the discovery of Faraday rotation toward radio source 3C 84, the active galactic nucleus in NGC 1275 at the core of the Perseus Cluster. The rotation measure (RM), determined from polarization observations at wavelengths of 1.3 and 0.9 mm, is (8.7 {\textpm} 2.3){\texttimes}105 rad m-2, among the largest ever measured. The RM remained relatively constant over a 2 yr period even as the intrinsic polarization position angle wrapped through a span of 300{\textopenbullet}. The Faraday rotation is likely to originate either in the boundary layer of the radio jet from the nucleus or in the accretion flow onto the central black hole. The accretion flow probably is disk-like rather than spherical on scales of less than a parsec, otherwise the RM would be even larger.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal},
	author = {Plambeck, R. L. and Bower, G. C. and Rao, Ramprasad and Marrone, D. P. and Jorstad, S. G. and Marscher, A. P. and Doeleman, S. S. and Fish, V. L. and Johnson, M. D.},
	month = nov,
	year = {2014},
	pages = {66},
	file = {Plambeck et al. - 2014 - PROBING THE PARSEC-SCALE ACCRETION FLOW OF 3C 84 W.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/HAZB28MZ/Plambeck et al. - 2014 - PROBING THE PARSEC-SCALE ACCRETION FLOW OF 3C 84 W.pdf:application/pdf},
}

@article{angelinelli_properties_2021,
	title = {Properties of clumps and filaments around galaxy clusters},
	volume = {653},
	issn = {0004-6361, 1432-0746},
	url = {http://arxiv.org/abs/2102.01096},
	doi = {10.1051/0004-6361/202140471},
	abstract = {We report on the possibility of studying the properties of cosmic diffuse baryons by studying self-gravitating clumps and filaments connected to galaxy clusters. While filaments are challenging to detect with X-ray observations, the higher density of clumps make them visible and a viable tracer to study the thermodynamical properties of baryons undergoing accretion along cosmic web filaments onto galaxy clusters. We developed new algorithms to identify these structures in a set of non-radiative high-resolution simulations of galaxy clusters, cosmological simulations of galaxy clusters. We show that the density and temperature of clumps are independent of the mass of the cluster where they reside. We detected a positive correlation between the filament temperature and the host cluster mass. Density and Temperature of clumps and filaments tend to correlate. Both decrease moving outward. We observe that clumps are hotter, more massive and more luminous if identified closer to the cluster center. Clumps and filaments contribute to \~{}17 (1) per cent of the gas mass (volume) outside R500,c, with clumps contributing a factor of 2 more. Especially in the outermost cluster regions (\~{}3{\textperiodcentered}R500,c or beyond) X-ray observations might already have the chance of locating filaments based on the distribution of clumps, and by studying the thermodynamics of diffuse baryons before they are processed by the dynamical interaction with the host intracluster medium.},
	language = {en},
	urldate = {2024-05-26},
	journal = {Astronomy \& Astrophysics},
	author = {Angelinelli, M. and Ettori, S. and Vazza, F. and Jones, T. W.},
	month = sep,
	year = {2021},
	note = {arXiv:2102.01096 [astro-ph]},
	keywords = {Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {A171},
	file = {Angelinelli et al. - 2021 - Properties of clumps and filaments around galaxy c.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/6SCZCIPD/Angelinelli et al. - 2021 - Properties of clumps and filaments around galaxy c.pdf:application/pdf},
}

@article{canning_filamentary_2014,
	title = {Filamentary star formation in {NGC} 1275},
	volume = {444},
	issn = {0035-8711, 1365-2966},
	url = {http://academic.oup.com/mnras/article/444/1/336/1008420/Filamentary-star-formation-in-NGC1275},
	doi = {10.1093/mnras/stu1191},
	abstract = {We examine the star formation in the outer halo of NGC 1275, the central galaxy in the Perseus cluster (Abell 426), using far-ultraviolet and optical images obtained with the Hubble Space Telescope. We have identified a population of very young, compact star clusters with typical ages of a few Myr. The star clusters are organized on multiple kiloparsec scales. Many of these star clusters are associated with {\textquoteleft}streaks{\textquoteright} of young stars, the combination of which has a cometary appearance. We perform photometry on the star clusters and diffuse stellar streaks, and fit their spectral energy distributions to obtain ages and masses. These young stellar populations appear to be normal in terms of their masses, luminosities and cluster formation efficiency; {\textless}10 per cent of the young stellar mass is located in star clusters. Our data suggest star formation is associated with the evolution of some of the giant gas filaments in NGC 1275 that become gravitationally unstable on reaching and possibly stalling in the outer galaxy. The stellar streaks then could represent stars moving on ballistic orbits in the potential well of the galaxy cluster. We propose a model where star-forming filaments, switched on \~{}50 Myr ago and are currently feeding the growth of the NGC 1275 stellar halo at a rate of ?-2 to 3 M yr-1. This type of process may also build stellar haloes and form isolated star clusters in the outskirts of youthful galaxies.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Canning, R. E. A. and Ryon, J. E. and Gallagher, J. S. and Kotulla, R. and O'Connell, R. W. and Fabian, A. C. and Johnstone, R. M. and Conselice, C. J. and Hicks, A. and Rosario, D. and Wyse, R. F. G.},
	month = oct,
	year = {2014},
	pages = {336--349},
	file = {Canning et al. - 2014 - Filamentary star formation in NGC 1275.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/53S2QPX7/Canning et al. - 2014 - Filamentary star formation in NGC 1275.pdf:application/pdf},
}

@article{gendron-marsolais_deep_2017,
	title = {Deep 230{\textendash}470 {MHz} {VLA} observations of the mini-halo in the {Perseus} cluster},
	volume = {469},
	issn = {0035-8711, 1365-2966},
	url = {https://academic.oup.com/mnras/article-lookup/doi/10.1093/mnras/stx1042},
	doi = {10.1093/mnras/stx1042},
	abstract = {We present a low-frequency view of the Perseus cluster with new observations from the Karl G. Jansky Very Large Array (JVLA) at 230{\textendash}470 MHz. The data reveal a multitude of new structures associated with the mini-halo. The mini-halo seems to be influenced both by the AGN activity and the sloshing motion of the cool core cluster{\textquoteright}s gas. In addition, it has a filamentary structure similar to that seen in radio relics found in merging clusters. We present a detailed description of the data reduction and imaging process of the dataset. The depth and resolution of the observations allow us to conduct for the first time a detailed comparison of the mini-halo structure with the X-ray structure as seen in the Chandra X-ray images. The resulting image very clearly shows that the mini-halo emission is mostly contained behind the western cold front, similar to that predicted by simulations of gas sloshing in galaxy clusters, but fainter emission is also seen beyond, as if particles are leaking out. However, due to the proximity of the Perseus cluster, as well as the quality of the data at low radio frequencies and at X-ray wavelengths, we also find evidence of fine structure. This structure includes several radial radio filaments extending in different directions, a concave radio structure associated with the southern X-ray bay and sharp radio edges that correlate with X-ray edges. Minihaloes are therefore not simply diffuse, uniform radio sources, but rather have a rich variety of complex structures. These results illustrate the high-quality images that can be obtained with the new JVLA at low radio frequencies, as well as the necessity to obtain deeper, higher fidelity radio images of mini-haloes in clusters to further understand their origin.},
	language = {en},
	number = {4},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Gendron-Marsolais, M. and Hlavacek-Larrondo, J. and Van Weeren, R. J. and Clarke, T. and Fabian, A. C. and Intema, H. T. and Taylor, G. B. and Blundell, K. M. and Sanders, J. S.},
	month = aug,
	year = {2017},
	pages = {3872--3880},
	file = {Gendron-Marsolais et al. - 2017 - Deep 230{\textendash}470 MHz VLA observations of the mini-halo.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/RPNHTWUW/Gendron-Marsolais et al. - 2017 - Deep 230{\textendash}470 MHz VLA observations of the mini-halo.pdf:application/pdf},
}

@article{qiu_formation_2020,
	title = {The formation of dusty cold gas filaments from galaxy cluster simulations},
	volume = {4},
	issn = {2397-3366},
	url = {http://arxiv.org/abs/2005.00549},
	doi = {10.1038/s41550-020-1090-7},
	abstract = {Galaxy clusters are the most massive collapsed structures in the universe whose potential wells are filled with hot, X-ray emitting intracluster medium. Observations however show that a significant number of clusters (the so-called cool-core clusters) also contain large amounts of cold gas in their centres, some of which is in the form of spatially extended filaments spanning scales of tens of kiloparsecs. These findings have raised questions about the origin of the cold gas, as well as its relationship with the central active galactic nucleus (AGN), whose feedback has been established as a ubiquitous feature in such galaxy clusters. Here we report a radiation hydrodynamic simulation of AGN feedback in a galaxy cluster, in which cold filaments form from the warm, AGN-driven outflows with temperatures between \$10{\textasciicircum}4\$ and \$10{\textasciicircum}7\$ K as they rise in the cluster core. Our analysis reveals a new mechanism, which, through the combination of radiative cooling and ram pressure, naturally promotes outflows whose cooling time is shorter than their rising time, giving birth to spatially extended cold gas filaments. Our results strongly suggest that the formation of cold gas and AGN feedback in galaxy clusters are inextricably linked and shed light on how AGN feedback couples to the intracluster medium.},
	language = {en},
	number = {9},
	urldate = {2024-05-26},
	journal = {Nature Astronomy},
	author = {Qiu, Yu and Bogdanovic, Tamara and Li, Yuan and McDonald, Michael and McNamara, Brian R.},
	month = may,
	year = {2020},
	note = {arXiv:2005.00549 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {900--906},
	file = {Qiu et al. - 2020 - The formation of dusty cold gas filaments from gal.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/3ATF2V86/Qiu et al. - 2020 - The formation of dusty cold gas filaments from gal.pdf:application/pdf},
}

@article{fabian_relationship_2003-1,
	title = {The relationship between the optical {Halpha} filaments and the {X}-ray emission in the core of the {Perseus} cluster},
	volume = {344},
	issn = {0035-8711, 1365-2966},
	url = {https://academic.oup.com/mnras/article/344/3/L48/1015434},
	doi = {10.1046/j.1365-8711.2003.06856.x},
	abstract = {NGC 1275 in the centre of the Perseus cluster of galaxies, Abell 426, is surrounded by a spectacular filamentary H$\alpha$ nebula. Deep Chandra X-ray imaging has revealed that the brighter outer filaments are also detected in soft X-rays. This can be due to conduction and mixing of the cold gas in the filaments with the hot, dense intracluster medium. We show the correspondence of the filaments in both wavebands and draw attention to the relationship of two prominent curved north-west filaments to an outer, buoyant radio bubble seen as a hole in the X-ray image. There is a strong resemblance in the shape of the hole and the disposition of the filaments to the behaviour of a large air bubble rising in water. If this is a correct analogy, then the flow is laminar and the intracluster gas around this radio source is not turbulent. We obtain a limit on the viscosity of this gas.},
	language = {en},
	number = {3},
	urldate = {2024-05-26},
	journal = {Monthly Notices of the Royal Astronomical Society},
	author = {Fabian, A. C. and Sanders, J. S. and Crawford, C. S. and Conselice, C. J. and Gallagher, J. S. and Wyse, R. F. G.},
	month = sep,
	year = {2003},
	pages = {L48--L52},
	file = {Fabian et al. - 2003 - The relationship between the optical Halpha filame.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/4GWDU76B/Fabian et al. - 2003 - The relationship between the optical Halpha filame.pdf:application/pdf},
}

@article{qiu_using_2019,
	title = {Using {H}\${\textbackslash}alpha\$ {Filaments} to {Probe} {AGN} {Feedback} in {Galaxy} {Clusters}},
	volume = {872},
	issn = {2041-8205, 2041-8213},
	url = {http://arxiv.org/abs/1812.05247},
	doi = {10.3847/2041-8213/ab0375},
	abstract = {Recent observations of giant ellipticals and brightest cluster galaxies (BCGs) provide tentative evidence for a correlation between the luminosity of the H$\alpha$ emitting gas filaments and the strength of feedback associated with the active galactic nucleus (AGN). Motivated by this, we use 3D radiationhydrodynamic simulations with the code Enzo to examine and quantify the relationship between the observable properties of the H$\alpha$ filaments and the kinetic and radiative feedback from supermassive black holes in BCGs. We find that the spatial extent and total mass of the filaments show positive correlations with AGN feedback power and can therefore be used as probes of the AGN activity. We also examine the relationship between the AGN feedback power and velocity dispersion of the H$\alpha$ filaments and find that the kinetic luminosity shows a statistically significant correlation with the component of the velocity dispersion along the jet axis, but not the components perpendicular to it.},
	language = {en},
	number = {1},
	urldate = {2024-05-26},
	journal = {The Astrophysical Journal Letters},
	author = {Qiu, Yu and Bogdanovic, Tamara and Li, Yuan and McDonald, Michael},
	month = feb,
	year = {2019},
	note = {arXiv:1812.05247 [astro-ph]},
	keywords = {Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {L11},
	file = {Qiu et al. - 2019 - Using H\$alpha\$ Filaments to Probe AGN Feedback in.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/BW9W3XQZ/Qiu et al. - 2019 - Using H\$alpha\$ Filaments to Probe AGN Feedback in.pdf:application/pdf},
}

@article{timmerman_very_2021,
	title = {Very {Large} {Array} observations of the mini-halo and {AGN} feedback in the {Phoenix} cluster},
	volume = {646},
	issn = {0004-6361, 1432-0746},
	url = {http://arxiv.org/abs/2009.13238},
	doi = {10.1051/0004-6361/202039075},
	abstract = {Methods. We present new multifrequency Very Large Array 1{\textendash}12 GHz observations of the Phoenix cluster which resolve the AGN and its lobes in all four frequency bands, and resolve the mini-halo in L- and S-band.
Results. Using our L-band observations, we measure the total flux density of the radio lobes at 1.5 GHz to be 7.6 {\textpm} 0.8 mJy, and the flux density of the mini-halo to be 8.5 {\textpm} 0.9 mJy. Using high-resolution images in L- and X-band, we produce the first spectral index maps of the lobes from the AGN and measure the spectral indices of the northern and southern lobes to be -1.35 {\textpm} 0.07 and -1.30 {\textpm} 0.12, respectively. Similarly, using L- and S-band data, we map the spectral index of the mini-halo, and obtain an integrated spectral index of $\alpha$ = -0.95 {\textpm} 0.10.
Conclusions. We find that the mini-halo is most likely formed by turbulent re-acceleration powered by sloshing in the cool core due to a recent merger. In addition, we find that the feedback in the Phoenix cluster is consistent with the picture that stronger cooling flows are to be expected for massive clusters like the Phoenix cluster, as these may feature an underweight supermassive black hole due to their merging history. Strong time variability of the AGN on Myr-timescales may help explain the disconnection between the radio and the X-ray properties of the system. Finally, a small amount of jet precession of the AGN likely contributes to the relatively low ICM re-heating efficiency of the mechanical feedback.},
	language = {en},
	urldate = {2024-05-26},
	journal = {Astronomy \& Astrophysics},
	author = {Timmerman, R. and van Weeren, R. J. and McDonald, M. and Ignesti, A. and McNamara, B. R. and Hlavacek-Larrondo, J. and R{\"o}ttgering, H. J. A.},
	month = feb,
	year = {2021},
	note = {arXiv:2009.13238 [astro-ph]},
	keywords = {Astrophysics - Cosmology and Nongalactic Astrophysics},
	pages = {A38},
	file = {Timmerman et al. - 2021 - Very Large Array observations of the mini-halo and.pdf:/home/crhea/snap/zotero-snap/common/Zotero/storage/T9KVGPGS/Timmerman et al. - 2021 - Very Large Array observations of the mini-halo and.pdf:application/pdf},
}