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We use James Webb Space Telescope Near-Infrared Camera Wide Field Slitless Spectroscopy (NIRCam WFSS) and the Near-Infrared spectrograph (NIRSpec) in the Cosmic Evolution Early Release survey to measure rest-frame optical emission-line ratios of 155 galaxies at z > 2. The blind NIRCam grism observations include a sample of galaxies with bright emission lines that were not observed on the NIRSpec masks. We study the changes of the H α , [O III ]/H β , and [Ne III ]/[O II ] emission lines in terms of redshift by comparing to lower-redshift SDSS, CLEAR, and MOSDEF samples. We find a significant (>3 σ ) correlation between [O III ]/H β with redshift, while [Ne III ]/[O II ] has a marginal (2 σ ) correlation with redshift. We compare [O III ]/H β and [Ne III ]/[O II ] to stellar mass and H β SFR. We find that both emission-line ratios have a correlation with H β SFR and an anticorrelation with stellar mass across the redshifts 0 < z < 9. Comparison with MAPPINGS V models indicates that these trends are consistent with lower metallicity and higher ionization in low-mass and high-SFR galaxies. We additionally compare to IllustrisTNG predictions and find that they effectively describe the highest [O III ]/H β ratios observed in our sample, without the need to invoke MAPPINGS models with significant shock ionization components.

We present the analysis of the stellar population and star formation history of 181 MIRI selected galaxies at z  = 0 − 3.5 in the massive galaxy cluster field SMACS J0723.3–7327, commonly referred to as SMACS0723, using the JWST Mid-Infrared Instrument (MIRI). We combine the data with the JWST Near Infrared Camera (NIRCam) catalogue, in conjunction with the Hubble Space Telescope (HST) WFC3/IR and ACS imaging. We find that the MIRI bands capture PAH features and dust emission, significantly enhancing the accuracy of photometric redshift and measurements of the physical properties of these galaxies. The median photo- z 's of galaxies with MIRI data are found to have a small 0.1 per cent difference from spectroscopic redshifts and reducing the error by 20 per cent. With MIRI data included in SED fits, we find that the measured stellar masses are unchanged, while the star formation rate is slightly lower by 0.1 dex. We also fit the median SED of active galactic nuclei (AGNs) and star-forming galaxies (SFG) separately. MIRI data provides tighter constraints on the AGN contribution, reducing the typical AGN contributions by ∼15 per cent. In addition, we also compare the median SED obtained with and without MIRI, and we find that including MIRI data yields steeper optical and UV slopes, indicating bluer colours, lower dust attenuation, and younger stellar populations. In the future, MIRI/MRS will enhance our understanding by providing more detailed spectral information and allowing for the study of specific emission features and diagnostics associated with AGN. [ABSTRACT FROM AUTHOR]

We present a comprehensive analysis of the evolution of the morphological and structural properties of a large sample of galaxies at z = 3–9 using early James Webb Space Telescope (JWST) CEERS NIRCam observations. Our sample consists of 850 galaxies at z > 3 detected in both Hubble Space Telescope (HST)/WFC3 and CEERS JWST/NIRCam images, enabling a comparison of HST and JWST morphologies. We conduct a set of visual classifications, with each galaxy in the sample classified three times. We also measure quantitative morphologies across all NIRCam filters. We find that galaxies at z > 3 have a wide diversity of morphologies. Galaxies with disks make up 60% of galaxies at z = 3, and this fraction drops to ∼30% at z = 6–9, while galaxies with spheroids make up ∼30%–40% across the redshift range, and pure spheroids with no evidence for disks or irregular features make up ∼20%. The fraction of galaxies with irregular features is roughly constant at all redshifts (∼40%–50%), while those that are purely irregular increases from ∼12% to ∼20% at z > 4.5. We note that these are apparent fractions, as many observational effects impact the visibility of morphological features at high redshift. On average, Spheroid-only galaxies have a higher Sérsic index, smaller size, and higher axis ratio than disk or irregular galaxies. Across all redshifts, smaller spheroid and disk galaxies tend to be rounder. Overall, these trends suggest that galaxies with established disks and spheroids exist across the full redshift range of this study, and further work with large samples at higher redshift is needed to quantify when these features first formed.

In an earlier paper, we determined the morphological types of galaxies in the Coma Cluster using data from the HST/ACS Coma Cluster treasury survey. Of the 132 members, 51 are non-dwarfs and 81 are dwarfs. We define dwarfs to have an absolute luminosity M F814W ≥ - 18.5 as in Marinova et al. (2012). In this paper, we identify the morphological types of these dwarf galaxies and conduct a detailed study of their properties. Using GALFIT, we determined the structural properties of our sample, and with spectroscopic redshifts, we determined memberships and distances to identify dwarfs. A visual examination of the residual images reveals that our sample of 78 dwarf galaxies comprises dwarf lenticular (dS0) 22%, dwarf elliptical (dE) 69%, dwarf spirals (dSp) 4%, dwarf ring (dring) 1%, dwarf barred spirals (dSBp) 3% and dwarf irregular (dIrr) 1% galaxies. The bulge-disk decomposition (Sérsic + exponential) fits are only good for the dS0 galaxies. The remainder of the sample gives good fits only for single Sérsic fits. The color-magnitude relation (CMR) shows that the dEs are redder and fainter than the rest of the sample (except one dIrr galaxy). The Kormendy relation reveals that dE galaxies have lower surface brightness than the rest of the sample. Our research leads us to conclude that dwarf galaxies appear to have a different formation and evolution process than non-dwarf galaxies. [ABSTRACT FROM AUTHOR]

As observations of the Epoch of Reionization (EoR) in redshifted 21 cm emission begin, we assess the accuracy of the early catalog results from the Precision Array for Probing the Epoch of Reionization (PAPER) and the Murchison Wide-field Array (MWA). The MWA EoR approach derives much of its sensitivity from subtracting foregrounds to <1% precision, while the PAPER approach relies on the stability and symmetry of the primary beam. Both require an accurate flux calibration to set the amplitude of the measured power spectrum. The two instruments are very similar in resolution, sensitivity, sky coverage, and spectral range and have produced catalogs from nearly contemporaneous data. We use a Bayesian Markov Chain Monte Carlo fitting method to estimate that the two instruments are on the same flux scale to within 20% and find that the images are mostly in good agreement. We then investigate the source of the errors by comparing two overlapping MWA facets where we find that the differences are primarily related to an inaccurate model of the primary beam but also correlated errors in bright sources due to clean. We conclude with suggestions for mitigating and better characterizing these effects. [ABSTRACT FROM AUTHOR]

Paper XIII of this series presented radial velocities for 406 stars in certain of the Clube Selected Areas, a set of areas systematically arranged in Galactic coordinates. We now complete the survey by providing the radial velocities, mostly obtained at the European Southern Observatory (ESO), of 625 stars in the six southernmost Areas. Each star has been measured at least twice; the mean velocities have standard errors typically of 0.2–0.3 km s−1. Additional observations made from Haute-Provence of many of the stars that are observable from there have helped to identify, and in some instances to characterize, the ∼70 spectroscopic binaries discovered in this programme. The final results of the programme, complementing those given in table 3 of Paper XIII, are summarized in Table 12 , which presents the mean velocities and velocity dispersions in the six southern Areas. It is noted that the difference between Paper XIII and this one as regards the provenance of the radial velocities has led to a small difference in zero-points, which is discussed in Section 3 and needs to be taken into account in any analysis of the combined data. [ABSTRACT FROM AUTHOR]

We present the radial velocity curve of a single-lined spectroscopic binary in the faint Hercules dwarf spheroidal (dSph) galaxy, based on 34 individual spectra covering more than 2 yr of observations. This is the first time that orbital elements could be derived for a binary in a dSph. The system consists of a metal-poor red giant and a low-mass companion, possibly a white dwarf, with a 135 day period in a moderately eccentric (e = 0.18) orbit. Its period and eccentricity are fully consistent with metal-poor binaries in the Galactic halo, while the projected semimajor axis is small, at ap sin i = 38 R☼. In fact, a very close orbit could inhibit the production of heavier elements through s-process nucleosynthesis, leading to the very low abundances of neutron-capture elements that are found in this star. We discuss the further implications for the chemical enrichment history of the Hercules dSph, but find no compelling binary scenario that could reasonably explain the full, peculiar abundance pattern of the Hercules dSph galaxy. [ABSTRACT FROM AUTHOR]

Using stacked emission-line flux measurements of cool circumgalactic gas (CGM) in lower-mass galaxies (109.0 ≤ M */ M ⊙ ≤ 1010.2), we measure the dependence of the emission characteristics on orientation relative to the disk plane as a function of radius and compare to what we found previously for massive (M * > 1010.4 M ⊙) early-type galaxies. Although the line ratios (the lower [N ii ]/H α and [O iii ]/H β) suggest an overall softer ionizing source than in the more massive galaxies, consistent with previous findings, we find the same ionization hardening signature (a higher [N ii ]/H α ratio in the inner polar region) along the polar direction at small radii that we found for the more massive galaxies. The line ratio in the inner polar bin is distinct from that measured for the inner planar bin with 99.99%, confidence and with >99.9% confidence we conclude that it lies outside the star formation regime. The effective hardening of the ionization of the CGM along the polar axis, at small radii, could indicate either relic effects of active galactic nucleus activity or shock ionization. In either case, this signature appears to be ubiquitous across the stellar mass range we are able to explore with our spectral stacking technique and currently available archival data. [ABSTRACT FROM AUTHOR]

The well-known cluster of galaxies ZwCl0024+1652 at z ∼ 0.4 lacks an in-depth morphological classification of its central region. While previous studies provide a visual classification of a patched area, we used the public code called gal axy S upport V ector M achine (galsvm) and HST /ACS data as well as the WFP2 master catalogue to automatically classify all cluster members up to 1 Mpc. galsvm analyses galaxy morphologies through support vector machine (SVM). From the 231 cluster galaxies, we classified 97 as early types (ETs) and 83 as late types (LTs). The remaining 51 stayed unclassified (or undecided). By cross-matching our results with the existing visual classification, we found an agreement of 81 per cent. In addition to previous Zwcl0024 morphological classifications, 121 of our galaxies were classified for the first time in this work. In addition, we tested the location of classified galaxies on the standard morphological diagrams, colour–colour and colour–magnitude diagrams. Out of all cluster members, ∼20 per cent are emission-line galaxies, taking into account previous GLACE results. We have verified that the ET fraction is slightly higher near the cluster core and decreases with the clustercentric distance, while the opposite trend has been observed for LT galaxies. We found a higher fraction of ETs (54  per cent) than LTs (46  per cent) throughout the analysed central region, as expected. In addition, we analysed the correlation between the five morphological parameters (Abraham concentration, Bershady–Concelice concentration, asymmetry, Gini, and M20 moment of light) and the clustercentric distance, without finding a clear trend. Finally, as a result of our work, the morphological catalogue of 231 galaxies containing all the measured parameters and the final classification is available in the electronic form of this paper. [ABSTRACT FROM AUTHOR]

Dual active galaxy nuclei (dAGNs) trace the population of post-merger galaxies and are the precursors to massive black hole (MBH) mergers, an important source of gravitational waves that may be observed by the Laser Interferometer Space Antenna (LISA). In Paper I of this series, we used the population of ≈2000 galaxy mergers predicted by the TNG50-3 simulation to seed semi-analytic models of the orbital evolution and coalescence of MBH pairs with initial separations of ≈1 kpc. Here, we calculate the dAGN luminosities and separations of these pairs as they evolve in post-merger galaxies, and show how the coalescence fraction of dAGNs changes with redshift. We find that because of the several gigayear-long dynamical friction timescale for orbital evolution, the fraction of dAGNs that eventually end in an MBH merger grows with redshift and exceeds 50% beyond z dAGN ≈ 1. Dual AGNs in galaxies with bulge masses ≲1010 M ⊙, or consisting of near-equal-mass MBHs, evolve more quickly and have higher than average coalescence fractions. At any redshift, dAGNs observed with small separations (≲0.7 kpc) have a higher probability of merging before z = 0 than more widely separated systems. Radiation feedback effects can significantly reduce the number of MBH mergers, and this could be manifested as a larger than expected number of widely separated dAGNs. We present a method to estimate the MBH coalescence rate as well as the potential LISA detection rate given a survey of dAGNs. Comparing these rates to the eventual LISA measurements will help determine the efficiency of dynamical friction in post-merger galaxies. [ABSTRACT FROM AUTHOR]

We present the completed KMOS3D survey, an integral field spectroscopic survey of 739 galaxies at 0.6 < z < 2.7 using the K-band Multi Object Spectrograph (KMOS) at the Very Large Telescope. The KMOS3D survey provides a population-wide census of kinematics, star formation, outflows, and nebular gas conditions both on and off the star-forming galaxy main sequence through the spatially resolved and integrated properties of Hα, [N ii], and [S ii] emission lines. We detect Hα emission for 91% of galaxies on the main sequence of star formation and 79% overall. The depth of the survey has allowed us to detect galaxies with star formation rates below 1 M⊙ yr−1, as well as to resolve 81% of detected galaxies with ≥3 resolution elements along the kinematic major axis. The detection fraction of Hα is a strong function of both color and offset from the main sequence, with the detected and nondetected samples exhibiting different spectral energy distribution shapes. Comparison of Hα and UV+IR star formation rates reveal that dust attenuation corrections may be underestimated by 0.5 dex at the highest masses (). We confirm our first year results of a high rotation-dominated fraction (monotonic velocity gradient and vrot/) of 77% for the full KMOS3D sample. The rotation-dominated fraction is a function of both stellar mass and redshift, with the strongest evolution measured over the redshift range of the survey for galaxies with . With this paper, we include a final data release of all 739 observed objects (http://www.mpe.mpg.de/ir/KMOS3D). [ABSTRACT FROM AUTHOR]

Stellar and black hole feedback heat and disperse surrounding cold gas clouds, launching gas flows off circumnuclear and galactic disks, producing a dynamic interstellar medium. On large scales bordering the cosmic web, feedback drives enriched gas out of galaxies and groups, seeding the intergalactic medium with heavy elements. In this way, feedback shapes galaxy evolution by shutting down star formation and ultimately curtailing the growth of structure after the peak at redshift 2–3. To understand the complex interplay between gravity and feedback, we must resolve both the key physics within galaxies and map the impact of these processes over large scales, out into the cosmic web. The Advanced X-ray Imaging Satellite (AXIS) is a proposed X-ray probe mission for the 2030s with arcsecond spatial resolution, large effective area, and low background. AXIS will untangle the interactions of winds, radiation, jets, and supernovae with the surrounding interstellar medium across the wide range of mass scales and large volumes driving galaxy evolution and trace the establishment of feedback back to the main event at cosmic noon. This white paper is part of a series commissioned for the AXIS Probe mission concept; additional AXIS white papers can be found at the AXIS website. [ABSTRACT FROM AUTHOR]

She et al. (Paper I) assembled a catalog of nearby galaxies observed with the Chandra X-ray observatory, by cross-matching galaxies in the NASA Extragalactic Database within 50 Mpc and the Chandra archive. That sample has enabled searches of low-mass black holes associated with late-type, bulgeless galaxies and studies of the accretion physics related to low-luminosity active galactic nuclei (AGNs). Using a similar approach, here we construct an extended catalog up to 150 Mpc and make a cross-correlation with a catalog of nearby galaxy groups. The new catalog consists of 1964 galaxies, out of which 1692 have a redshift-independent distance, 1557 are listed in the galaxy group catalog with group properties available, and 782 are identified to be X-ray AGN candidates. Compared with the AGN sample in Paper I, the new sample is 2.5 times larger in size (782 versus 314), with ∼80% of the new members having an Eddington ratio less than 10−4. We confirm that the conclusions based on the previous sample remain. With the new sample, we compare AGN fractions between early-type and late-type galaxies, and between central and satellite galaxies in groups, and find no significant difference. This suggests that the secular process is not the dominant mechanism feeding AGNs in the local universe. [ABSTRACT FROM AUTHOR]

This white paper explores the detectability of intermediate-mass black holes (IMBHs) wandering in the Milky Way (MW) and massive local galaxies, with a particular emphasis on the role of AXIS. IMBHs, ranging within 10 3 − 6 M ⊙ , are commonly found at the centers of dwarf galaxies and may exist, yet undiscovered, in the MW. By using model spectra for advection-dominated accretion flows (ADAFs), we calculated the expected fluxes emitted by a population of wandering IMBHs with masses of 10 5 M ⊙ in various MW environments and extrapolated our results to massive local galaxies. Around 40 % of the potential population of wandering IMBHs in the MW can be detected in an AXIS deep field. We proposed criteria to aid with selecting IMBH candidates using already available optical surveys. We also showed that IMBHs wandering in >200 galaxies within 10 Mpc can be easily detected with AXIS when passing within dense galactic environments (e.g., molecular clouds and cold neutral medium). In summary, we highlighted the potential X-ray detectability of wandering IMBHs in local galaxies and provided insights for guiding future surveys. Detecting wandering IMBHs is crucial for understanding their demographics and evolution and the merging history of galaxies. This white paper is part of a series commissioned for the AXIS Probe Concept Mission; additional AXIS white papers can be found at the AXIS website. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the benefits of teaming up data from the radio to the far-infrared (FIR) regime for the characterization of dusty star-forming galaxies (DSFGs). These galaxies are thought to be the star-forming progenitors of local massive quiescent galaxies and to play a pivotal role in the reconstruction of the cosmic star formation rate density up to high redshift. Due to their dust-enshrouded nature, DSFGs are often invisible in the near-infrared/optical/UV bands. Therefore, they necessitate observations at longer wavelengths, primarily the FIR band, where dust emission occurs, and the radio band, which is not affected by dust absorption. Combining data from these two spectral windows makes it possible to characterize even the dustiest objects, enabling the retrieval of information about their age, dust temperature, and star-formation status, and facilitates the differentiation between various galaxy populations that evolve throughout cosmic history. Despite the detection of faint radio sources being a challenging task, this study demonstrates that an effective strategy to build statistically relevant samples of DSFGs would be reaching deep sensitivities in the radio band, even restricted to smaller areas, and then combining these radio observations with FIR/submm data. Additionally, this paper quantifies the improvement in the spectral energy distribution (SED) reconstruction of DSFGs by incorporating ALMA band measurements, in particular, in its upgraded status thanks to the anticipated Wideband Sensitivity Upgrade. [ABSTRACT FROM AUTHOR]

The recurrent activity of radio AGN, with phases of activity alternating with periods of quiescence, has been known since the early studies of these objects. The full relevance of this cycle is emphasised by the requirement, from the AGN feedback scenario, of a recurrent impact of the energy released by the SMBH during the lifetime of the host galaxy: only in this way can AGN feedback influence galaxy evolution. Radio AGN in different evolutionary phases can be identified by their properties, like morphology and spectral indices. Dying/remnant and restarted sources have been the most elusive to select and characterise, but they are crucial to quantify the full life cycle. Thanks to the availability of new, large radio surveys (particularly at low frequencies), it is finally possible to make a more complete census of these rare sources and start building larger samples. This paper gives an overview of the recent work conducted using a variety of radio telescopes and surveys, highlighting some of the new results characterising the properties of dying/remnant and restarted radio sources and what has been learned about the life cycle of radio AGN. The comparison with the predictions from numerical simulations is also discussed. The results so far show that remnant and restarted radio AGN have a variety of properties which make these objects more complex than previously thought. [ABSTRACT FROM AUTHOR]

Magnetic fields in galaxies are usually originated through the action of a dynamo, which is based on the helicity of turbulent flows (alpha effect) and nonrigid rotation of a galaxy (differential rotation). They are opposed by dissipation, which tends to destroy the regular structures of the field. As a rule, dynamo equations contain averaged turbulence parameters. This approach presents difficulties in the case of galaxies with a highly inhomogeneous interstellar medium, associated, for example, with star formation. One way to solve the problem is to use random coefficients in the field equations. In this case, solutions require separate statistical analysis. This paper examines various statistical moments for the galactic magnetic field within the framework of a model assuming fluctuations of the alpha effect and turbulent diffusion. [ABSTRACT FROM AUTHOR]

We are merging a large participatory science effort with machine learning to enhance the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX). Our overall goal is to remove false positives, allowing us to use lower signal-to-noise data and sources with low goodness-of-fit. With six million classifications through Dark Energy Explorers, we can confidently determine if a source is not real at over 94% confidence level when classified by at least 10 individuals; this confidence level increases for higher signal-to-noise sources. To date, we have only been able to apply this direct analysis to 190,000 sources. The full sample of HETDEX will contain around 2–3 million sources, including nearby galaxies ([O ii ] emitters), distant galaxies (Ly α emitters or LAEs), false positives, and contamination from instrument issues. We can accommodate this tenfold increase by using machine learning with visually vetted samples from Dark Energy Explorers. We have already increased by over tenfold the number of sources that have been visually vetted from our previous pilot study where we only had 14,000 visually vetted LAE candidates. This paper expands on the previous work by increasing the visually vetted sample from 14,000 to 190,000. In addition, using our currently visually vetted sample, we generate a real or false positive classification for the full candidate sample of 1.2 million LAEs. We currently have approximately 17,000 volunteers from 159 countries around the world. Thus, we are applying participatory or citizen scientist analysis to our full HETDEX data set, creating a free educational opportunity that requires no prior technical knowledge. [ABSTRACT FROM AUTHOR]

Several large JWST blank field observing programs have not yet discovered the first galaxies expected to form at 15 ≤ z ≤ 20. This has motivated the search for more effective survey strategies that will be able to effectively probe this redshift range. Here, we explore the use of gravitationally lensed cluster fields, which have historically been the most effective discovery tool with the Hubble Space Telescope. In this paper, we analyze the effectiveness of the most massive galaxy clusters that provide the highest median magnification factor within a single JWST NIRCam module in uncovering this population. The results of exploiting these lensing clusters to break the z > 15 barrier are compared against the results from large-area, blank-field surveys such as JADES and CEERS in order to determine the most effective survey strategy for JWST. We report that the fields containing massive foreground galaxy clusters specifically chosen to occupy the largest fraction of a single NIRCam module with high magnification factors in the source plane while containing all multiple images in the image plane within a single module provide the highest probability of both probing the 15 ≤ z ≤ 20 regime as well as discovering the highest-redshift galaxy possible with JWST. We also find that using multiple massive clusters in exchange for shallower survey depths is a more time-efficient method of probing the z > 15 regime. [ABSTRACT FROM AUTHOR]