Massive Galaxies Research Articles

Formation of collisional ring galaxies in Milgromian dynamics

ABSTRACT Ring galaxies are rare in the Universe. A head-on or off-centre collision between an intruder galaxy and a disc galaxy leads to a collisional ring galaxy (CRG) when the intruder-to-target mass ratio (ITMR) is over 0.1 in Newtonian dynamics. Within the framework of Milgromian dynamics, the strong equivalence principle is violated due to the presence of an external field. When two galaxies collide towards each other, the dynamical mass of the phantom dark halo in a galaxy is suppressed by the external field induced by the other galaxy. As a consequence of such suppression, the gravitational perturbation for the target galaxy introduced by a collision is weakened. In this case, a minor collision may not be capable of generating a CRG. In this work, we address this issue and perform a series of numerical simulations of collisions by tuning the values of ITMR. We find that the critical ITMR is 0.5 in MOND, which is much larger than that in Newtonian dynamics. The observed massive ring galaxies, such as Arp 147, can be effectively interpreted by CRGs in Milgrom’s Modified Newtonian Dynamics (MOND). This interpretation does not necessitate the presence of dark matter halos for either the target or intruder galaxies. Moreover, for a larger inclination angle or a larger impact parameter, the off-centred ring structure is fainter. The larger critical ITMR indicates that it is harder to form a CRG in MOND. To account for the observed ring structures of the NGC 922-like galaxies in MOND, it is necessary to invoke other scenarios than a dry minor collision.

The internal dynamics and environments of Relics and compact massive ETGs with TNG50

ABSTRACT Relic galaxies are massive, compact, and quiescent objects observed in the local Universe that have not experienced any significant interaction episodes or merger events since about z = 2, remaining relatively unaltered since their formation. On the other hand, massive and compact early-type galaxies (cETGs) in the local Universe appear to show similar properties to Relic galaxies, despite having substantial accretion history. Relic galaxies, with frozen history, can provide important clues about the intrinsic processes related to the evolutionary pathways of ETGs and the role that mergers play in their evolution. Using the high-resolution cosmological simulation TNG50-1 from IllustrisTNG project, we investigate the assembly history of a sample of massive, compact, old, and quiescent subhaloes split by satellite accretion fraction. We compare the evolutionary pathways at three cosmic epochs: z = 2, z = 1.5, and z = 0, using the orbital decomposition numerical method to investigate the stellar dynamics of each galactic kinematical component and their environmental correlations. Our results point to a steady pathway across time that is not strongly dependent on the mergers or the environment. Relics and cETGs do not show a clear preference for high- or low-density environments within the volume explored at z = 0, as they are found in both scenarios. However, the progenitors of Relic galaxies have consistently resided in high-density environments since z = 2, while cETGs were shifted to such environments at a later stage. The merger history can be recovered from the stellar kinematics imprints in the local Universe. Relics and cETGs show consistently dynamical similarities at z = 2 and differences at z = 0 to disc, bulge, and hot inner stellar halo. In the current scenario, the mergers that drive the growth of cETGs do not give rise to a new and distinct evolutionary pathway when compared to Relics.

The Fast and Furious in JWST high-[formula omitted] galaxies

Recent JWST surveys reveal a striking abundance of massive galaxies at cosmic dawn, earlier than predicted by ΛCDM. The implied speed-up in galaxy formation by gravitational collapse is reminiscent of short-period galaxy dynamics described by the baryonic Tully–Fisher relation. This may originate in weak gravitation tracking the de Sitter scale of acceleration adS=cH, where c is the velocity of light and H(z)∝1+z3/2 is the Hubble parameter with redshift z. With no free parameters, this produces a speed-up in early galaxy formation by an order of magnitude with essentially no change in initial galaxy mass function. It predicts a deceleration parameter q0=1−2π/GAadS2=−0.98±0.5, where G is Newton’s constant and A=(47±6)M⊙(km/s)−4 is the baryonic Tully–Fisher coefficient (McGaugh 2012). At 3σ significance, it identifies dynamical dark energy alleviating H0-tension when combined with independent q0 estimates in the Local Distance Ladder. Conclusive determination of q0=dlog(θ(z)H(z))/dz|z=0 is expected from BAO angle θ(z) observations by the recently launched Euclid mission.

EMU/GAMA: A technique for detecting active galactic nuclei in low mass systems

Abstract We propose a new method for identifying active galactic nuclei (AGN) in low mass ( $\mathrm{M}_*\leq10^{10}\mathrm{M}_\odot$ ) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an excess over that expected from star formation alone. Combining data in the Galaxy and Mass Assembly (GAMA) G23 region from GAMA, Evolutionary Map of the Universe (EMU) early science observations, and Wide-field Infrared Survey Explorer (WISE), we compare this technique with a selection of different AGN diagnostics to explore the similarities and differences in AGN classification. We find that diagnostics based on optical and near-infrared criteria (the standard BPT diagram, the WISE colour criterion, and the mass-excitation, or MEx diagram) tend to favour detection of AGN in high mass, high luminosity systems, while the “ProSpect” SED fitting tool can identify AGN efficiently in low mass systems. We investigate an explanation for this result in the context of proportionally lower mass black holes in lower mass galaxies compared to higher mass galaxies and differing proportions of emission from AGN and star formation dominating the light at optical and infrared wavelengths as a function of galaxy stellar mass. We conclude that SED-derived AGN classification is an efficient approach to identify low mass hosts with low radio luminosity AGN.

A Census of Star Formation Histories of Massive Galaxies at 0.6 < z < 1 from Spectrophotometric Modeling Using Bagpipes and Prospector

We present individual star formation histories (SFHs) of ∼3000 massive galaxies (log(M */M ⊙) > 10.5) from the Large Early Galaxy Astrophysics Census spectroscopic survey at a lookback time of ∼7 billion yr and quantify the population trends leveraging 20 hr deep-integrated spectra of these ∼1800 star-forming and ∼1200 quiescent galaxies at 0.6 < z < 1.0. Essentially all galaxies at this epoch contain stars of age <3 Gyr, in contrast with older massive galaxies today, facilitating better recovery of previous generations of star formation at cosmic noon and earlier. We conduct spectrophotometric analysis using parametric and nonparametric Bayesian stellar population synthesis modeling tools—Bagpipes and Prospector—to constrain the median SFHs of this mass complete sample and characterize population trends. A consistent picture arises for the late-time stellar mass growth when quantified as t 50 and t 90, corresponding to the age of the Universe when galaxies formed 50% and 90% of their total stellar mass, although the two methods disagree at the earliest formation times (e.g., t 10). Our results reveal trends in both stellar mass and stellar velocity dispersion as in the local Universe—low-mass galaxies with shallower potential wells grow their stellar masses later in cosmic history compared to high-mass galaxies. Unlike local quiescent galaxies, the median duration of late-time star formation (τ SF,late = t 90–t 50) does not consistently depend on the stellar mass. This census sets a benchmark for future deep spectrophotometric studies of the more distant Universe.

Direct Formation of Massive Black Holes via Dynamical Collapse in Metal-enriched Merging Galaxies at z ∼ 10: Fully Cosmological Simulations

We present the results of the first fully cosmological hydrodynamical simulations studying the merger-driven model for massive black hole (BH) seed formation via direct collapse. Using the zoom-in technique as well as particle splitting, we achieve a final spatial resolution of 2 pc. We show that the major merger of two massive galaxies at redshift z ∼ 8 results in the formation of a nuclear supermassive disk (SMD) of only 4 pc in radius, owing to a prodigious gas inflow sustained at 100–1000 M ⊙ yr−1. The core of the merger remnant is metal-rich, well above solar abundance, and the SMD reaches a gaseous mass of 3 × 108 M ⊙ in less than a million years after the merger, despite a concurrent prominent nuclear starburst. Dynamical heating as gas falls into the deepest part of the potential well, and heating and stirring by supernova blastwaves, generate a turbulent multiphase interstellar medium, with a gas velocity dispersion exceeding 100 km s−1. As a result, only moderate fragmentation occurs in the inner 10–20 pc, despite the temperature falling below 1000 K. The SMD is Jeans-unstable as well as bar-unstable and will collapse further adiabatically, becoming warm and ionized. We show that the SMD, following inevitable contraction, will become general-relativistic-unstable and directly form a supermassive BH of mass in the range 106–108 M ⊙, essentially skipping the stage of BH seed formation. These results confirm that mergers between the most massive galaxies at z ∼ 8–10 can naturally explain the rapid emergence of bright high-redshift quasars.

Nature versus Nurture: Revisiting the Environmental Impact on Star Formation Activities of Galaxies

We present a systematic study of the environmental impact on star formation activities of galaxies using a mass-complete sample of ∼170k galaxies at z < 4 from the latest COSMOS2020 catalog. At z < 1, we find that the mean star formation rate (SFR) of all galaxies decreases with increasing density of the environment. However, when we only consider star-forming galaxies, the mean SFR becomes independent of the environment at z < 1. At z > 2, we observe a clear positive correlation between the SFR and the density of the environment for all the galaxies. On the other hand, the stellar mass of the galaxies increases significantly with the environment at all redshifts except for star-forming galaxies at z < 1. The fraction of quiescent galaxies increases with increasing density of the environment at z < 2, and the morphology–density relation is confirmed to be present up to z ∼ 1. We also find that environmental quenching is negligible at z > 1, whereas mass quenching is the dominant quenching mechanism for massive galaxies at all redshifts. Based on these results, we argue that stellar mass-regulated physical processes might be the major driving force for star formation activities of galaxies. At low redshift (z < 1) massive galaxies are quenched primarily due to their high mass, resulting in a normal SFR–density relation. At high redshift (z > 2) most of the galaxies are star-forming ones tightly following the star-forming main sequence, and the difference in their stellar mass in different environments naturally leads to a reversal of the SFR–density relation.

Less is less: Photometry alone cannot predict the observed spectral indices of z ~ 1 galaxies from the LEGA-C spectroscopic survey

Aims. We test whether we can predict optical spectra from deep-field photometry of distant galaxies. Our goal is to perform a comparison in data space, highlighting the differences between predicted and observed spectra. Methods. The Large Early Galaxy Astrophysics Census (LEGA-C) provides high-quality optical spectra of thousands of galaxies at redshift 0.6 &lt; z &lt; 1. Broadband photometry of the same galaxies, drawn from the recent COSMOS2020 catalog, is used to predict the optical spectra with the spectral energy distribution (SED) fitting code Prospector and the MILES stellar library. The observed and predicted spectra are compared in terms of two age and metallicity-sensitive absorption features (HδA and Fe4383). Results. The global bimodality of star-forming and quiescent galaxies in photometric space is recovered with the model spectra. However, the presence of a systematic offset in the Fe4383 line strength and the weak correlation between the observed and modeled line strength imply that accurate age or metallicity determinations cannot be inferred from photometry alone. Conclusions. For now we caution that photometry-based estimates of stellar population properties are determined mostly by the modeling approach and not the physical properties of galaxies, even when using the highest-quality photometric datasets and state-of-the-art fitting techniques. When exploring a new physical parameter space (i.e. redshift or galaxy mass) high-quality spectroscopy is always needed to inform the analysis of photometry.

Galaxy catalogs from the Sage Semi-Analytic Model calibrated on The Three Hundred hydrodynamical simulations: A method to push the limits toward lower mass galaxies in dark matter only clusters simulations

The new generation of upcoming deep photometric and spectroscopic surveys will allow us to measure the astrophysical properties of faint galaxies in massive clusters. This would demand to produce simulations of galaxy clusters with better mass resolution than the ones available today if we want to make comparisons between the upcoming observations and predictions of cosmological models. But producing full-physics hydrodynamical simulations of the most massive clusters is not an easy task. This would involve billions of computational elements to reliably resolve low mass galaxies similar to those measured in observations. On the other hand, dark matter only simulations of cluster size halos can be done with much larger mass resolution but at the cost of having to apply a model that populate galaxies within each of the subhalos in these simulations. In this paper we present the results of a new set of dark matter only simulations with different mass resolutions within the The Three Hundred project. We have generated catalogs of galaxies with stellar and luminosity properties by applying the Sage Semi-Analytical Model of galaxy formation. To obtain the catalogs consistent with the results from hydrodynamical simulations, the internal physical parameters of Sage were calibrated with the Particle Swarm Optimization method using a subset of full-physics runs with the same mass resolution than the dark matter only ones.

Proposed Host Galaxies of Repeating Fast Radio Burst Sources Detected by CHIME/FRB

We present a search for host galaxy associations for the third set of repeating fast radio burst (FRB) sources discovered by the CHIME/FRB Collaboration. Using the ∼1′ CHIME/FRB baseband localizations and probabilistic methods, we identify potential host galaxies of two FRBs, 20200223B and 20190110C at redshifts of 0.06024(2) and 0.12244(6), respectively. We also discuss the properties of a third marginal candidate host galaxy association for FRB 20191106C with a host redshift of 0.10775(1). The three putative host galaxies are all relatively massive, fall on the standard mass–metallicity relationship for nearby galaxies, and show evidence of ongoing star formation. They also all show signatures of being in a transitional regime, falling in the green valley, which is between the bulk of star-forming and quiescent galaxies. The plausible host galaxies identified by our analysis are consistent with the overall population of repeating and nonrepeating FRB hosts while increasing the fraction of massive and bright galaxies. Coupled with these previous host associations, we identify a possible excess of FRB repeaters whose host galaxies have M u − M r colors redder than the bulk of star-forming galaxies. Additional precise localizations are required to confirm this trend.

Dynamical Stellar Mass-to-light Ratio Gradients: Evidence for Very Centrally Concentrated IMF Variations in ETGs?

Evidence from different probes of the stellar initial mass function (IMF) of massive early-type galaxies (ETGs) has repeatedly converged on IMFs more bottom heavy than in the Milky Way (MW). This consensus has come under scrutiny due to often contradictory results from different methods on the level of individual galaxies. In particular, a number of strong lensing probes are ostensibly incompatible with a non-MW IMF. Radial gradients of the IMF—related to gradients of the stellar mass-to-light ratio ϒ—can potentially resolve this issue. We construct Schwarzschild models allowing for ϒ-gradients in seven massive ETGs with MUSE and SINFONI observations. We find dynamical evidence that ϒ increases toward the center for all ETGs. The gradients are confined to subkiloparsec scales. Our results suggest that constant-ϒ models may overestimate the stellar mass of galaxies by up to a factor of 1.5. For all except one galaxy, we find a radius where the total dynamical mass has a minimum. This minimum places the strongest constraints on the IMF outside the center and appears at roughly 1 kpc. We consider the IMF at this radius characteristic for the main body of each ETG. In terms of the IMF mass-normalization α relative to a Kroupa IMF, we find on average an MW-like IMF 〈α main〉 = 1.03 ± 0.19. In the centers, we find concentrated regions with increased mass normalizations that are less extreme than previous studies suggested, but still point to a Salpeter-like IMF, 〈α cen〉 = 1.54 ± 0.15.

O Corona, where art thou? eROSITA’s view of UV-optical-IR variability-selected massive black holes in low-mass galaxies

Finding massive black holes (MBHs, MBH ≈ 104–107 M⊙) in the nuclei of low-mass galaxies $\left( {{M_*}\mathop {\mathop &lt; \limits_ }\limits_ {{10}^{10}}{M_ \odot }} \right)$ is crucial to constrain seeding and growth of black holes over cosmic time, but it is particularly challenging due to their low accretion luminosities. Variability selection via long-term photometric ultraviolet, optical, or infrared (UVOIR) light curves has proved effective and identifies lower-Eddington ratios compared to broad and narrow optical spectral lines searches. In the inefficient accretion regime, X-ray and radio searches are effective, but they have been limited to small samples. Therefore, differences between selection techniques have remained uncertain. Here, we present the first large systematic investigation of the X-ray properties of a sample of known MBH candidates in dwarf galaxies. We extracted X-ray photometry and spectra of a sample of ~200 UVOIR variability-selected MBHs and significantly detected 17 of them in the deepest available SRG/eROSITA image, of which four are newly discovered X-ray sources and two are new secure MBHs. This implies that tens to hundreds of LSST MBHs will have SRG/eROSITA counterparts, depending on the seeding model adopted. Surprisingly, the stacked X-ray images of the many non-detected MBHs are incompatible with standard disk-corona relations, typical of active galactic nuclei, inferred from both the optical and radio fluxes. They are instead compatible with the X-ray emission predicted for normal galaxies. After careful consideration of potential biases, we identified that this X-ray weakness needs a physical origin. A possibility is that a canonical X-ray corona might be lacking in the majority of this population of UVOIR-variability selected low-mass galaxies or that unusual accretion modes and spectral energy distributions are in place for MBHs in dwarf galaxies. This result reveals the potential for severe biases in occupation fractions derived from data from only one waveband combined with SEDs and scaling relations of more massive black holes and galaxies.

Uncovering a Massive z ∼ 7.7 Galaxy Hosting a Heavily Obscured Radio-loud Active Galactic Nucleus Candidate in COSMOS-Web

In this Letter, we report the discovery of the highest redshift, heavily obscured, radio-loud (RL) active galactic nucleus (AGN) candidate selected using JWST NIRCam/MIRI, mid-IR, submillimeter, and radio imaging in the COSMOS-Web field. Using multifrequency radio observations and mid-IR photometry, we identify a powerful, RL, growing supermassive black hole with significant spectral steepening of the radio spectral energy distribution (f 1.28 GHz ∼ 2 mJy, q 24 μm = −1.1, α 1.28−3 GHz = − 1.2, Δα = − 0.4). In conjunction with ALMA, deep ground-based observations, ancillary space-based data, and the unprecedented resolution and sensitivity of JWST, we find no evidence of AGN contribution to the UV/optical/near-infrared (NIR) data and thus infer heavy amounts of obscuration (N H > 1023 cm−2). Using the wealth of deep UV to submillimeter photometric data, we report a singular solution photo-z of z phot = 7.7−0.3+0.4 and estimate an extremely massive host galaxy (logM⋆=11.92±0.5M⊙) hosting a powerful, growing supermassive black hole​​​​​ (L Bol = 4−12x × 1046 erg s−1). This source represents the farthest known obscured RL AGN candidate, and its level of obscuration aligns with the most representative but observationally scarce population of AGN at these epochs.

Identification of Galaxy Protoclusters Based on the Spherical Top-hat Collapse Theory

We propose a new method for finding galaxy protoclusters that is motivated by structure formation theory and also directly applicable to observations. We adopt the conventional definition that a protocluster is a galaxy group whose virial mass M vir < M cl at its epoch, where M cl = 1014 M ⊙, but would exceed that limit when it evolves to z = 0. We use the critical overdensity for complete collapse at z = 0 predicted by the spherical top-hat collapse model to find the radius and total mass of the regions that would collapse at z = 0. If the mass of a region centered at a massive galaxy exceeds M cl, the galaxy is at the center of a protocluster. We define the outer boundary of a protocluster as the zero-velocity surface at the turnaround radius so that the member galaxies are those sharing the same protocluster environment and showing some conformity in physical properties. We use the cosmological hydrodynamical simulation Horizon Run 5 (HR5) to calibrate this prescription and demonstrate its performance. We find that the protocluster identification method suggested in this study is quite successful. Its application to the high-redshift HR5 galaxies shows a tight correlation between the mass within the protocluster regions identified according to the spherical collapse model and the final mass to be found within the clusters at z = 0, meaning that the regions can be regarded as the bona fide protoclusters with high reliability. We also confirm that the redshift-space distortion does not significantly affect the performance of the protocluster identification scheme.

An effective description of Laniakea: impact on cosmology and the local determination of the Hubble constant

We propose an effective model to describe the bias induced on cosmological observables by Laniakea, the gravitational supercluster hosting the Milky Way, which was defined using peculiar velocity data from Cosmicflows-4 (CF4). The structure is well described by an ellipsoidal shape exhibiting triaxial expansion, reasonably approximated by a constant expansion rate along the principal axes. Our best fits suggest that the ellipsoid, after subtracting the background expansion, contracts along the two smaller axes and expands along the longest one, predicting an average expansion of ∼ -1.1 km/s/Mpc. The different expansion rates within the region, relative to the mean cosmological expansion, induce line-of-sight-dependent corrections in the computation of luminosity distances. We apply these corrections to two low-redshift datasets: the Pantheon+ catalog of type Ia Supernovae (SN Ia), and 63 measurements of Surface Brightness Fluctuations (SBF) of early-type massive galaxies from the MASSIVE survey. We find corrections on the distances of order ∼ 2-3%, resulting in a shift in the inferred best-fit values of the Hubble constant H 0 of order ΔH 0 SN Ia ≈ 0.5 km/s/Mpc and ΔH 0 SBF ≈ 1.1 km/s/Mpc, seemingly worsening the Hubble tension.

HINORA, a method for detecting ring-like structures in 3D point distributions I: Application to the Local Volume Galaxy catalogue

Abstract We present a new method – called HINORA (HIgh-NOise RANdom SAmple Consensus) – for the identification of regular structures in 3D point distributions. Motivated by the possible existence of the so-called Council of Giants, that is, a ring of 12 massive galaxies surrounding the Local Group in the Local Sheet with a radius of 3.75 Mpc, we apply HINORA to the Local Volume Galaxy catalogue confirming its existence. When varying the lower limit of K-band luminosity of the galaxy entering the catalogue, we further report on the existence of another ring-like structure in the Local Volume that now contains the Milky Way and M31. However, this newly found structure is dominated by low-mass (satellite) galaxies. While we here simply present the novel method as well as its first application to observational data, follow-up work using numerical simulations of cosmic structure formation shall shed light into the origin of such regular patterns in the galaxy distribution. Further, the method is equally suited to identify similar (or even different) structures in various kinds of astrophysical data (e.g. locating the actual ‘baryonic-acoustic oscillation spheres’ in galaxy redshift surveys).

Early high-resolution millimeter-wave maps from ToITEC

TolTEC is a polarization-sensitive camera at millimeter wavelengths with unprecedented sensitivity and 5-10 arcsecond resolution in three photometric bands. TolTEC achieved first light on the 50-meter Large Millimeter Telescope in July 2022, just prior to a planned summer telescope maintenance shutdown, and began commissioning observations when the telescope resumed observations in December 2022. The commissioning program consisted of observations of targeted nebulae, molecular clouds, polarized quasars, galaxies, and clusters of galaxies. The goals of these observations include demonstrating the science capabilities of the camera and characterizing the performance and instrumental properties, including noise, beams, and polarization sensitivity in its three bands centered at 1.1, 1.4, and 2.0 mm |with angular resolutions of 5, 6, and 10 arcseconds, respectively. We present early results from the commissioning observations of the Crab Nebula. Upcoming observations will include selected proposals from the broader astronomy community in Mexico and the United States, as well as legacy surveys focused on mapping galactic molecular clouds, cold dust emission in local galaxies, polarized dust emission in filaments around star-forming regions, massive galaxy clusters, and distant obscured star-forming galaxies.

Signatures of Massive Black Hole Merger Host Galaxies from Cosmological Simulations. I. Unique Galaxy Morphologies in Imaging

Low-frequency gravitational-wave experiments such as the Laser Interferometer Space Antenna and pulsar timing arrays are expected to detect individual massive black hole (MBH) binaries and mergers. However, secure methods of identifying the exact host galaxy of each MBH merger among the large number of galaxies in the gravitational-wave localization region are currently lacking. We investigate the distinct morphological signatures of MBH merger host galaxies, using the Romulus25 cosmological simulation. We produce mock telescope images of 201 simulated galaxies in Romulus25 hosting recent MBH mergers through stellar population synthesis and dust radiative transfer. Based on comparisons to mass- and redshift-matched control samples, we show that combining multiple morphological statistics via a linear discriminant analysis enables identification of the host galaxies of MBH mergers, with accuracies that increase with chirp mass and mass ratio. For mergers with high chirp masses (≳108.2 M ⊙) and high mass ratios (≳0.5), the accuracy of this approach reaches ≳80%, and does not decline for at least ∼1 Gyr after numerical merger. We argue that these trends arise because the most distinctive morphological characteristics of MBH merger and binary host galaxies are prominent classical bulges, rather than relatively short-lived morphological disturbances from their preceding galaxy mergers. Since these bulges are formed though major mergers of massive galaxies, they lead to (and become permanent signposts for) MBH binaries and mergers that have high chirp masses and mass ratios. Our results suggest that galaxy morphology can aid in identifying the host galaxies of future MBH binaries and mergers.

First Results from the JWST Early Release Science Program Q3D: Powerful Quasar-driven Galactic Scale Outflow at z = 3

Quasar-driven galactic outflows are a major driver of the evolution of massive galaxies. We report observations of a powerful galactic-scale outflow in a z = 3 extremely red and intrinsically luminous (L bol ≃ 5 × 1047erg s−1) quasar SDSSJ1652 + 1728 with the Near-infrared Spectrograph on board JWST. We analyze the kinematics of rest-frame optical emission lines and identify the quasar-driven outflow extending out to ∼10 kpc from the quasar with a velocity offset of (v r = ± 500 km s−1) and high velocity dispersion (FWHM = 700–2400 km s−1). Due to JWST’s unprecedented surface brightness sensitivity in the near-infrared, we unambiguously show that the powerful high velocity outflow in an extremely red quasar encompasses a large swath of the host galaxy’s interstellar medium. Using the kinematics and dynamics of optical emission lines, we estimate the mass outflow rate—in the warm ionized phase alone—to be at least 2300 ± 1400 M ⊙ yr−1. We measure a momentum flux ratio between the outflow and the quasar accretion disk of ∼1 on a kpc scale, indicating that the outflow was likely driven in a relatively high (>1023cm−2) column density environment through radiation pressure on dust grains. We find a coupling efficiency between the bolometric luminosity of the quasar and the outflow of 0.1%, matching the theoretical prediction of the minimum coupling efficiency necessary for negative quasar feedback. The outflow has sufficient energetics to drive the observed turbulence seen in shocked regions of the quasar host galaxy, which are likely directly responsible for prolonging the time that it takes for gas to cool efficiently.

A machine learning method to infer clusters of galaxies mass radial profiles from mock Sunyaev-Zel’dovich maps with The Three Hundred clusters

Our study introduces a new machine learning algorithm for estimating 3D cumulative radial profiles of total and gas mass in galaxy clusters from thermal Sunyaev-Zel’dovich (SZ) effect maps. We generate mock images from 2522 simulated clusters, employing an autoencoder and random forest in our approach. Notably, our model makes no prior assumptions about hydrostatic equilibrium. Our results indicate that the model successfully reconstructs unbiased total and gas mass profiles, with a scatter of approximately 10%. We analyse clusters in various dynamical states and mass ranges, finding that our method’s accuracy and precision are consistent. We verify the capabilities of our model by comparing it with the hydrostatic equilibrium technique, showing that it accurately recovers total mass profiles without any bias.