Searcharxiv⌕ Search

arXiv subjects

M. Gaspari

Publications and source records attributed to M. Gaspari.

At least 91 records · Page 5Linked to original sources

Thermodynamic properties, multiphase gas and AGN feedback in a large sample of giant ellipticals

We present a study of the thermal structure of the hot X-ray emitting atmospheres for a sample of 49 nearby X-ray and optically bright elliptical galaxies using {\it Chandra} X-ray data. We focus on the connection between the properties of the hot X-ray emitting gas and the cooler H$α$+[NII] emitting phase, and the possible role of the latter in the AGN (Active Galactic Nuclei) feedback cycle. We do not find evident correlations between the H$α$+[NII] emission and global properties such as X-ray luminosity, mass of hot gas, and gas mass fraction. We find that the presence of H$α$+[NII] emission is more likely in systems with higher densities, lower entropies, shorter cooling times, shallower entropy profiles, lower values of min($t_{\rm cool}/t_{\rm ff}$), and disturbed X-ray morphologies (linked to turbulent motions). However, we see no clear separations in the observables obtained for galaxies with and without optical emission line nebulae. The AGN jet powers of the galaxies with X-ray cavities show hint of a possible weak positive correlation with their H$α$+[NII] luminosities. This correlation and the observed trends in the thermodynamic properties may result from chaotic cold accretion (CCA) powering AGN jets, as seen in some high-resolution hydrodynamic simulations.

astro-ph.GA↗

Non-thermal pressure support in X-COP galaxy clusters

Galaxy clusters are the endpoints of structure formation and are continuously growing through the merging and accretion of smaller structures. Numerical simulations predict that a fraction of their energy content is not yet thermalized, mainly in the form of kinetic motions (turbulence, bulk motions). Measuring the level of non-thermal pressure support is necessary to understand the processes leading to the virialization of the gas within the potential well of the main halo and to calibrate the biases in hydrostatic mass estimates. We present high-quality measurements of hydrostatic masses and intracluster gas fraction out to the virial radius for a sample of 12 nearby clusters with available XMM-Newton and Planck data. We compare our hydrostatic gas fractions with the expected universal gas fraction to constrain the level of non-thermal pressure support. We find that hydrostatic masses require little correction and infer a median non-thermal pressure fraction of $\sim6\%$ and $\sim10\%$ at $R_{500}$ and $R_{200}$, respectively. Our values are lower than the expectations of hydrodynamical simulations, possibly implying a faster thermalization of the gas. If instead we use the mass calibration adopted by the Planck team, we find that the gas fraction of massive local systems implies a mass bias $1-b=0.85\pm0.05$ for SZ-derived masses, with some evidence for a mass-dependent bias. Conversely, the high bias required to match Planck CMB and cluster count cosmology is excluded by the data at high significance, unless the most massive halos are missing a substantial fraction of their baryons.

astro-ph.CO↗

Athena X-IFU synthetic observations of galaxy clusters to probe the chemical enrichment of the Universe

Answers to the metal production of the Universe can be found in galaxy clusters, notably within their Intra-Cluster Medium (ICM). The X-ray Integral Field Unit (X-IFU) on board the next-generation European X-ray observatory Athena (2030s) will provide the necessary leap forward in spatially-resolved spectroscopy required to disentangle the intricate mechanisms responsible for this chemical enrichment. In this paper, we investigate the future capabilities of the X-IFU in probing the hot gas within galaxy clusters. From a test sample of four clusters extracted from cosmological hydrodynamical simulations, we present comprehensive synthetic observations of these clusters at different redshifts (up to z = 2) and within the scaled radius R500 performed using the instrument simulator SIXTE. Through 100 ks exposures, we demonstrate that the X-IFU will provide spatially-resolved mapping of the ICM physical properties with little to no biases (<5%) and well within statistical uncertainties. The detailed study of abundance profiles and abundance ratios within R500 also highlights the power of the X-IFU in providing constraints on the various enrichment models. From synthetic observations out to z = 2, we also quantify its ability to track the chemical elements across cosmic time with excellent accuracy, and thereby to investigate the evolution of metal production mechanisms as well as the link to the stellar initial mass-function. Our study demonstrates the unprecedented capabilities of the X-IFU in unveiling the properties of the ICM but also stresses the data analysis challenges faced by future high-resolution X-ray missions such as Athena.

astro-ph.CO↗

The Close AGN Reference Survey (CARS): SOFIA detects spatially-resolved [CII] emission in the luminous AGN HE0433-1028

We report spatially-resolved [CII]$λ158$ $μ$m observations of HE 0433-1028, which is the first detection of a nearby luminous AGN (redshift 0.0355) with FIFI-LS onboard the airborne observatory SOFIA. We compare the spatially-resolved star formation tracers [CII], as provided by our SOFIA observations, and H$α$ from MUSE optical integral-field spectroscopy. We find that the [CII] emission is mainly matching the extended star formation as traced by the extinction-corrected H$α$ line emission but some additional flux is present. While a larger sample is needed to statistically confirm our findings and investigate possible dependencies on AGN luminosity and star formation rate, our study underlines the necessity of collecting a spatially-resolved optical-FIR dataset for nearby AGNs, and shows that it is technically feasible to collect such datasets with FIFI-LS onboard SOFIA.

astro-ph.GA↗

Measuring turbulence and gas motions in galaxy clusters via synthetic Athena X-IFU observations

The X-ray Integral Field Unit (X-IFU) that will be on board the Athena telescope will provide an unprecedented view of the intracluster medium (ICM) kinematics through the observation of gas velocity, $v$, and velocity dispersion, $w$, via centroid-shift and broadening of emission lines, respectively. The improvement of data quality and quantity requires an assessment of the systematics associated with this new data analysis, namely biases, statistical and systematic errors, and possible correlations between the different measured quantities. We have developed an end-to-end X-IFU simulator that mimics a full X-ray spectral fitting analysis on a set of mock event lists, obtained using SIXTE. We have applied it to three hydrodynamical simulations of a Coma-like cluster that include the injection of turbulence. This allowed us to assess the ability of X-IFU to map five physical quantities in the cluster core: emission measure, temperature, metal abundance, velocity and velocity dispersion. Finally, starting from our measurements maps, we computed the 2D structure function (SF) of emission measure fluctuations, $v$ and $w$ and compared them with those derived directly from the simulations. All quantities match with the input projected values without bias; the systematic errors were below 5%, except for velocity dispersion whose error reaches about 15%. Moreover, all measurements prove to be statistically independent, indicating the robustness of the fitting method. Most importantly, we recover the slope of the SFs in the inertial regime with excellent accuracy, but we observe a systematic excess in the normalization of both SF$_v$ and SF$_w$ ascribed to the simplistic assumption of uniform and (bi-)Gaussian measurement errors. Our work highlights the excellent capabilities of Athena X-IFU in probing the thermodynamic and kinematic properties of the ICM. (abridged)

astro-ph.CO↗

Digging for red nuggets: discovery of hot halos surrounding massive, compact, relic galaxies

We present the results of Chandra X-ray observations of the isolated, massive, compact, relic galaxies MRK 1216 and PGC 032873. Compact massive galaxies observed at z>2, also called red nuggets, formed in quick dissipative events and later grew by dry mergers into the local giant ellipticals. Due to the stochastic nature of mergers, a few of the primordial massive galaxies avoided the mergers and remained untouched over cosmic time. We find that the hot atmosphere surrounding MRK 1216 extends far beyond the stellar population and has an 0.5-7 keV X-ray luminosity of $L_{\rm X}=(7.0\pm0.2)\times10^{41}$ erg s$^{-1}$, which is similar to the nearby X-ray bright giant ellipticals. The hot gas has a short central cooling time of $\sim50$ Myr and the galaxy has a $\sim13$ Gyr old stellar population. The presence of an X-ray atmosphere with a short nominal cooling time and the lack of young stars indicate the presence of a sustained heating source, which prevented star formation since the dissipative origin of the galaxy 13 Gyrs ago. The central temperature peak and the presence of radio emission in the core of the galaxy indicate that the heating source is radio-mechanical AGN feedback. Given that both MRK 1216 and PGC 032873 appear to have evolved in isolation, the order of magnitude difference in their current X-ray luminosity could be traced back to a difference in the ferocity of the AGN outbursts in these systems. Finally, we discuss the potential connection between the presence of hot halos around such massive galaxies and the growth of super/over-massive black holes via chaotic cold accretion.

astro-ph.GA↗

Revisiting the Cooling Flow Problem in Galaxies, Groups, and Clusters of Galaxies

We present a study of 107 galaxies, groups, and clusters spanning ~3 orders of magnitude in mass, ~5 orders of magnitude in central galaxy star formation rate (SFR), ~4 orders of magnitude in the classical cooling rate (dM/dt) of the intracluster medium (ICM), and ~5 orders of magnitude in the central black hole accretion rate. For each system in this sample, we measure dM/dt using archival Chandra X-ray data and acquire the SFR and systematic uncertainty in the SFR by combining over 330 estimates from dozens of literature sources. With these data, we estimate the efficiency with which the ICM cools and forms stars, finding e_cool = SFR/(dM/dt) = 1.4 +/- 0.4% for systems with dM/dt > 30 Msun/yr. For these systems, we measure a slope in the SFR-dM/dt relation greater than unity, suggesting that the systems with the strongest cool cores are also cooling more efficiently. We propose that this may be related to, on average, higher black hole accretion rates in the strongest cool cores, which could influence the total amount (saturating near the Eddington rate) and dominant mode (mechanical vs radiative) of feedback. For systems with dM/dt < 30 Msun/yr, we find that the SFR and dM/dt are uncorrelated, and show that this is consistent with star formation being fueled at a low (but dominant) level by recycled ISM gas in these systems. We find an intrinsic log-normal scatter in SFR at fixed dM/dt of 0.52 +/- 0.06 dex, suggesting that cooling is tightly self-regulated over very long timescales, but can vary dramatically on short timescales. There is weak evidence that this scatter may be related to the feedback mechanism, with the scatter being minimized (~0.4 dex) in systems for which the mechanical feedback power is within a factor of two of the cooling luminosity.

astro-ph.HE↗

Shaken Snow Globes: Kinematic Tracers of the Multiphase Condensation Cascade in Massive Galaxies, Groups, and Clusters

We propose a novel method to constrain turbulence and bulk motions in massive galaxies, groups and clusters, exploring both simulations and observations. As emerged in the recent picture of the top-down multiphase condensation, the hot gaseous halos are tightly linked to all other phases in terms of cospatiality and thermodynamics. While hot halos (10^7 K) are perturbed by subsonic turbulence, warm (10^4 K) ionized and neutral filaments condense out of the turbulent eddies. The peaks condense into cold molecular clouds (< 100 K) raining in the core via chaotic cold accretion (CCA). We show all phases are tightly linked via the ensemble (wide-aperture) velocity dispersion along the line of sight. The correlation arises in complementary long-term AGN feedback simulations and high-resolution CCA runs, and is corroborated by the combined Hitomi and new IFU measurements in Perseus cluster. The ensemble multiphase gas distributions are characterized by substantial spectral line broadening (100-200 km/s) with mild line shift. On the other hand, pencil-beam detections sample the small-scale clouds displaying smaller broadening and significant line shift up to several 100 km/s, with increased scatter due to the turbulence intermittency. We present new ensemble sigma_v of the warm Halpha+[NII] gas in 72 observed cluster/group cores: the constraints are consistent with the simulations and can be used as robust proxies for the turbulent velocities, in particular for the challenging hot plasma (otherwise requiring extremely long X-ray exposures). We show the physically motivated criterion C = t_cool/t_eddy ~ 1 best traces the condensation extent region and presence of multiphase gas in observed clusters/groups. The ensemble method can be applied to many available datasets and can substantially advance our understanding of multiphase halos in light of the next-generation multiwavelength missions.

astro-ph.GA↗

Cosmological hydrodynamical simulations of galaxy clusters: X-ray scaling relations and their evolution

We analyse cosmological hydrodynamical simulations of galaxy clusters to study the X-ray scaling relations between total masses and observable quantities such as X-ray luminosity, gas mass, X-ray temperature, and $Y_{X}$. Three sets of simulations are performed with an improved version of the smoothed particle hydrodynamics GADGET-3 code. These consider the following: non-radiative gas, star formation and stellar feedback, and the addition of feedback by active galactic nuclei (AGN). We select clusters with $M_{500} > 10^{14} M_{\odot} E(z)^{-1}$, mimicking the typical selection of Sunyaev-Zeldovich samples. This permits to have a mass range large enough to enable robust fitting of the relations even at $z \sim 2$. The results of the analysis show a general agreement with observations. The values of the slope of the mass-gas mass and mass-temperature relations at $z=2$ are 10 per cent lower with respect to $z=0$ due to the applied mass selection, in the former case, and to the effect of early merger in the latter. We investigate the impact of the slope variation on the study of the evolution of the normalization. We conclude that cosmological studies through scaling relations should be limited to the redshift range $z=0-1$, where we find that the slope, the scatter, and the covariance matrix of the relations are stable. The scaling between mass and $Y_X$ is confirmed to be the most robust relation, being almost independent of the gas physics. At higher redshifts, the scaling relations are sensitive to the inclusion of AGNs which influences low-mass systems. The detailed study of these objects will be crucial to evaluate the AGN effect on the ICM.

astro-ph.CO↗

Deep Chandra observations of the stripped galaxy group falling into Abell 2142

In the local Universe, the growth of massive galaxy clusters mainly operates through the continuous accretion of group-scale systems. The infalling group in Abell 2142 is the poster child of such an accreting group, and as such, it is an ideal target to study the astrophysical processes induced by structure formation. We present the results of a deep (200 ks) observation of this structure with Chandra, which highlights the complexity of this system in exquisite detail. In the core of the group, the spatial resolution of Chandra reveals the presence of a leading edge and a complex AGN-induced activity. The morphology of the stripped gas tail appears straight in the innermost 250 kpc, suggesting that magnetic draping efficiently shields the gas from its surroundings. However, beyond $\sim300$ kpc from the core, the tail flares and the morphology becomes strongly irregular, which could be explained by a breaking of the drape, e.g. because of turbulent motions. The power spectrum of surface-brightness fluctuations is relatively flat ($P_{2D}\propto k^{-2.3}$), which indicates that thermal conduction is strongly inhibited even beyond the region where magnetic draping is effective. The amplitude of density fluctuations in the tail is consistent with a mild level of turbulence with a Mach number $M_{3D}\sim0.1-0.25$. Overall, our results show that the processes leading to the thermalization and mixing of the infalling gas are slow and relatively inefficient.

astro-ph.GA↗

On the connection between turbulent motions and particle acceleration in galaxy clusters

Giant radio halos are Mpc-scale diffuse radio sources associated with the central regions of galaxy clusters. The most promising scenario to explain the origin of these sources is that of turbulent re-acceleration, in which MeV electrons injected throughout the formation history of galaxy clusters are accelerated to higher energies by turbulent motions mostly induced by cluster mergers. In this Letter, we use the amplitude of density fluctuations in the intracluster medium as a proxy for the turbulent velocity and apply this technique to a sample of 51 clusters with available radio data. Our results indicate a segregation in the turbulent velocity of radio halo and radio quiet clusters, with the turbulent velocity of the former being on average higher by about a factor of two. The velocity dispersion recovered with this technique correlates with the measured radio power through the relation $P_{\rm radio}\proptoσ_v^{3.3\pm0.7}$, which implies that the radio power is nearly proportional to the turbulent energy rate. Our results provide an observational confirmation of a key prediction of the turbulent re-acceleration model and possibly shed light on the origin of radio halos.

astro-ph.HE↗

Kinetic and radiative power from optically thin accretion flows

We perform a set of general relativistic, radiative, magneto-hydrodynamical simulations (GR-RMHD) to study the transition from radiatively inefficient to efficient state of accretion on a non-rotating black hole. We study ion to electron temperature ratios ranging from $T_{\rm i}/T_{\rm e}=10$ to $100$, and simulate flows corresponding to accretion rates as low as $10^{-6}\dot M_{\rm Edd}$, and as high as $10^{-2}\dot M_{\rm Edd}$. We have found that the radiative output of accretion flows increases with accretion rate, and that the transition occurs earlier for hotter electrons (lower $T_{\rm i}/T_{\rm e}$ ratio). At the same time, the mechanical efficiency hardly changes and accounts to ${\approx}\,3\%$ of the accreted rest mass energy flux, even at the highest simulated accretion rates. This is particularly important for the mechanical AGN feedback regulating massive galaxies, groups, and clusters. Comparison with recent observations of radiative and mechanical AGN luminosities suggests that the ion to electron temperature ratio in the inner, collisionless accretion flow should fall within $10<T_{\rm i}/T_{\rm e}<30$, i.e., the electron temperature should be several percent of the ion temperature.

astro-ph.HE↗

Unifying the micro and macro properties of AGN feeding and feedback

We unify the feeding and feedback of supermassive black holes with the global properties of galaxies, groups, and clusters, by linking for the first time the physical mechanical efficiency at the horizon and Mpc scale. The macro hot halo is tightly constrained by the absence of overheating and overcooling as probed by X-ray data and hydrodynamic simulations ($\varepsilon_{\rm BH} \simeq$ 10$^{-3}\, T_{\rm x,7.4}$). The micro flow is shaped by general relativistic effects tracked by state-of-the-art GR-RMHD simulations ($\varepsilon_\bullet \simeq$ 0.03). The SMBH properties are tied to the X-ray halo temperature $T_{\rm x}$, or related cosmic scaling relation (as $L_{\rm x}$). The model is minimally based on first principles, as conservation of energy and mass recycling. The inflow occurs via chaotic cold accretion (CCA), the rain of cold clouds condensing out of the quenched cooling flow and recurrently funneled via inelastic collisions. Within 100s gravitational radii, the accretion energy is transformed into ultrafast 10$^4$ km s$^{-1}$ outflows (UFOs) ejecting most of the inflowing mass. At larger radii the energy-driven outflow entrains progressively more mass: at roughly kpc scale, the velocities of the hot/warm/cold outflows are a few 10$^3$, 1000, 500 km s$^{-1}$, with median mass rates ~10, 100, several 100 M$_\odot$ yr$^{-1}$, respectively. The unified CCA model is consistent with the observations of nuclear UFOs, and ionized, neutral, and molecular macro outflows. We provide step-by-step implementation for subgrid simulations, (semi)analytic works, or observational interpretations which require self-regulated AGN feedback at coarse scales, avoiding the a-posteriori fine-tuning of efficiencies.

astro-ph.HE↗

The Remarkable Similarity of Massive Galaxy Clusters From z~0 to z~1.9

We present the results of a Chandra X-ray survey of the 8 most massive galaxy clusters at z>1.2 in the South Pole Telescope 2500 deg^2 survey. We combine this sample with previously-published Chandra observations of 49 massive X-ray-selected clusters at 0 0.2R500 scaling like E(z)^2. In the centers of clusters (r<0.1R500), we find significant deviations from self similarity (n_e ~ E(z)^{0.1+/-0.5}), consistent with no redshift dependence. When we isolate clusters with over-dense cores (i.e., cool cores), we find that the average over-density profile has not evolved with redshift -- that is, cool cores have not changed in size, density, or total mass over the past ~9-10 Gyr. We show that the evolving "cuspiness" of clusters in the X-ray, reported by several previous studies, can be understood in the context of a cool core with fixed properties embedded in a self similarly-evolving cluster. We find no measurable evolution in the X-ray morphology of massive clusters, seemingly in tension with the rapidly-rising (with redshift) rate of major mergers predicted by cosmological simulations. We show that these two results can be brought into agreement if we assume that the relaxation time after a merger is proportional to the crossing time, since the latter is proportional to H(z)^(-1).

astro-ph.CO↗

Preferential Heating and Acceleration of Heavy Ions in Impulsive Solar Flares

We simulate decaying turbulence in a homogeneous pair plasma using three dimensional electromagnetic particle-in-cell (PIC) method. A uniform background magnetic field permeates the plasma such that the magnetic pressure is three times larger than the thermal pressure and the turbulence is generated by counter-propagating shear Alfvén waves. The energy predominately cascades transverse to the background magnetic field, rendering the turbulence anisotropic at smaller scales. We simultaneously move several ion species of varying charge to mass ratios in our simulation and show that the particles of smaller charge to mass ratios are heated and accelerated to non-thermal energies at a faster rate, in accordance with the enhancement of heavy ions and non-thermal tail in their energy spectrum observed in the impulsive solar flares. We further show that the heavy ions are energized mostly in the direction perpendicular to the background magnetic field with a rate consistent with our analytical estimate of the rate of heating due to cyclotron resonance with the Alfvén waves of which a large fraction is due to obliquely propagating waves.

physics.space-ph↗

The history of chemical enrichment in the intracluster medium from cosmological simulations

The distribution of metals in the intracluster medium (ICM) of galaxy clusters provides valuable information on their formation and evolution, on the connection with the cosmic star formation and on the effects of different gas processes. By analyzing a sample of simulated galaxy clusters, we study the chemical enrichment of the ICM, its evolution, and its relation with the physical processes included in the simulation and with the thermal properties of the core. These simulations, consisting of re-simulations of 29 Lagrangian regions performed with an upgraded version of the SPH GADGET-3 code, have been run including two different sets of baryonic physics: one accounts for radiative cooling, star formation, metal enrichment and supernova (SN) feedback, and the other one further includes the effects of feedback from active galactic nuclei (AGN). In agreement with observations, we find an anti-correlation between entropy and metallicity in cluster cores, and similar radial distributions of heavy-element abundances and abundance ratios out to large cluster-centric distances (~R180). In the outskirts, namely outside of ~0.2R180, we find a remarkably homogeneous metallicity distribution, with almost flat profiles of the elements produced by either SNIa or SNII. We investigated the origin of this phenomenon and discovered that it is due to the widespread displacement of metal-rich gas by early (z>2-3) AGN powerful bursts, acting on small high-redshift haloes. Our results also indicate that the intrinsic metallicity of the hot gas for this sample is on average consistent with no evolution between z=2 and z=0, across the entire radial range.

astro-ph.CO↗

Pressure of the hot gas in simulations of galaxy clusters

We analyze the radial pressure profiles, the ICM clumping factor and the Sunyaev-Zel'dovich (SZ) scaling relations of a sample of simulated galaxy clusters and groups identified in a set of hydrodynamical simulations based on an updated version of the TreePM-SPH GADGET-3 code. Three different sets of simulations are performed: the first assumes non-radiative physics, the others include, among other processes, AGN and/or stellar feedback. Our results are analyzed as a function of redshift, ICM physics, cluster mass and cluster cool-coreness or dynamical state. In general, the mean pressure profiles obtained for our sample of groups and clusters show a good agreement with X-ray and SZ observations. Simulated cool-core (CC) and non-cool-core (NCC) clusters also show a good match with real data. We obtain in all cases a small (if any) redshift evolution of the pressure profiles of massive clusters, at least back to z=1. We find that the clumpiness of gas density and pressure increases with the distance from the cluster center and with the dynamical activity. The inclusion of AGN feedback in our simulations generates values for the gas clumping ($\sqrt C_ρ\sim 1.2$ at $R_{200}$) in good agreement with recent observational estimates. The simulated $Y_{SZ}-M$ scaling relations are in good accordance with several observed samples, especially for massive clusters. As for the scatter of these relations, we obtain a clear dependence on the cluster dynamical state, whereas this distinction is not so evident when looking at the subsamples of CC and NCC clusters.

astro-ph.CO↗

Raining on black holes and massive galaxies: the top-down multiphase condensation model

The atmospheres filling massive galaxies, groups, and clusters display remarkable similarities with rainfalls. Such plasma halos are shaped by AGN heating and subsonic turbulence (~150 km/s), as probed by Hitomi. The new 3D high-resolution simulations show the soft X-ray (< 1 keV) plasma cools rapidly via radiative emission at the high-density interface of the turbulent eddies, stimulating a top-down condensation cascade of warm, $10^4$ K filaments. The ionized (optical/UV) filaments extend up to several kpc and form a skin enveloping the neutral filaments (optical/IR/21-cm). The peaks of the warm filaments further condense into cold molecular clouds (<50 K; radio) with total mass up to several $10^7$ M$_\odot$, i.e., 5/50$\times$ the neutral/ionized masses. The multiphase structures inherit the chaotic kinematics and are dynamically supported. In the inner 500 pc, the clouds collide in inelastic way, mixing angular momentum and leading to chaotic cold accretion (CCA). The BHAR can be modeled via quasi-spherical viscous accretion with collisional mean free path ~100 pc. Beyond the inner kpc region pressure torques drive the angular momentum transport. In CCA, the BHAR is recurrently boosted up to 2 dex compared with the disc evolution, which arises as turbulence is subdominant. The CCA BHAR distribution is lognormal with pink noise power spectrum characteristic of fractal phenomena. The rapid self-similar CCA variability can explain the light curve variability of AGN and HMXBs. An improved criterium to trace thermal instability is proposed. The 3-phase CCA reproduces crucial observations of cospatial multiphase gas in massive galaxies, as Chandra X-ray images, SOAR H$α$ warm filaments and kinematics, Herschel [C$^+$] emission, and ALMA giant molecular associations. CCA plays key role in AGN feedback, AGN unification/obscuration, the evolution of BHs, galaxies, and clusters.

astro-ph.GA↗