MXDFz4.4 - a LyC Emitter 250 Myr after the Epoch of Reionization and a First Test of Lyα Morphology as a Tracer of LyC Escape at High Redshift: #Galaxy Transforming Neighborhood: https://science.nasa.gov/missions/hubble/hubble-details-early-galaxy-transforming-neighborhood/
Replaced article(s) found for astro-ph.GA. https://arxiv.org/list/astro-ph.GA/new
[1/2]:
- GA-NIFS: Powerful and frequent outflows in moderate-luminosity active galactic nuclei at $z\sim3-6$
Giacomo Venturi, et al.
https://arxiv.org/abs/2512.09996 https://mastoxiv.page/@arXiv_astrophGA_bot/115705753776819617
- ALMA High-J CO Spectroscopy of High-Redshift Galaxies. II. 0.03" Resolution CO Kinematics Reveal ...
Ken-ichi Tadaki
https://arxiv.org/abs/2603.01352 https://mastoxiv.page/@arXiv_astrophGA_bot/116164867046260901
- Very long-term relaxation of harmonic 1D self-gravitating systems
Kerwann Tep, Jean-Baptiste Fouvry, Christophe Pichon
https://arxiv.org/abs/2603.11238 https://mastoxiv.page/@arXiv_astrophGA_bot/116220857983732581
- The tidal evolution of satellite galaxies in cosmological simulations: insights from COLIBRE
Feihong He, et al.
https://arxiv.org/abs/2604.03105 https://mastoxiv.page/@arXiv_astrophGA_bot/116356854403461047
- Deriving volume density profiles of filaments from observed surface densities
Alexander Men'shchikov, Guo-Yin Zhang
https://arxiv.org/abs/2604.12570 https://mastoxiv.page/@arXiv_astrophGA_bot/116407809964147819
- Reduced Incidence of Little Red Dots at z < 3 from Number Density and Halo Mass Evolution
Chenxuan Zhang, Huanian Zhang, Qingwen Wu, Luis C. Ho, Jian-Min Wang
https://arxiv.org/abs/2606.02773 https://mastoxiv.page/@arXiv_astrophGA_bot/116685196830855300
- The Hubble Missing Globular Clusters Survey IV. Ultra-faint compact satellites of the Milky Way. ...
M. Bellazzini, et al.
https://arxiv.org/abs/2606.12517 https://mastoxiv.page/@arXiv_astrophGA_bot/116736072691643849
- Nebular_AGN: A CIGALE module for fitting AGN emission lines
Hao Zhang, Patrice Theule, Veronique Buat, Denis Burgarella, Estelle Pons, Mederic Boquien
https://arxiv.org/abs/2606.14643 https://mastoxiv.page/@arXiv_astrophGA_bot/116753094453286560
- Assembly bias from nuisance to probe I: the relation between galactic conformity and the linear m...
Nelson Padilla, Ivan Lacerna, Dante Paz
https://arxiv.org/abs/2607.04022 https://mastoxiv.page/@arXiv_astrophGA_bot/116877882568563713
- Enabling Cosmic Web Analysis at Gigaparsec Scales: A Multi Block Approach for DisPerSE
Ankit Singh, Frazer Pearce, Meghan Gray, Gustavo Yepes
https://arxiv.org/abs/2607.14785 https://mastoxiv.page/@arXiv_astrophGA_bot/116934310782158818
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Star formation powers optical line emission from the CGM
Huanian Zhang, Lizhi Xie, Zhijie Qu, Dennis Zaritsky, Luis C. Ho, Min Bao, Fabio Fontanot, Michaela Hirschmann, Chenxu Liu, Gabriella De Lucia, Enci Wang, Haoyan Zheng
https://arxiv.org/abs/2607.18385 https://arxiv.org/pdf/2607.18385 https://arxiv.org/html/2607.18385
arXiv:2607.18385v1 Announce Type: new
Abstract: Using integral field spectroscopy, we explore the disk-halo interface, or the inner circumgalactic medium (CGM), of individual galaxies by constructing and analyzing emission-line maps for a large sample (72) of normal, low-redshift galaxies spanning three orders of magnitude in stellar mass and four orders in star formation rate (SFR). We find a steep turnover occurring at $(1-2) R_e$ in the H$\alpha$, [O {\small II}], and [O {\small III}] line emission radial profiles. Beyond this radius, the slope of the line emission radial profiles becomes shallower as the SFR of the central galaxy decreases, which might reflect the strength of the feedback processes. The line emission fluxes at large radius ($(5-10) R_e$ or $\sim (0.1-0.25)r_{\rm vir}$) correlate with the galaxy's SFR, but not with its stellar mass. These findings suggest that ionizing photons escaping from star-forming regions in the central galaxy account for the observed emission line fluxes from the inner CGM, with escape fractions inferred from the [O {\small III}] and [O {\small II}] ratio. Different state-of-the-art theoretical models do not agree on the predicted dependence of cool gas on the SFR of the central galaxies, highlighting the importance of CGM emission line measurements to distinguish between different subgrid models for star formation and feedback processes.
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Vz-GAL Dusty Star-Forming Galaxies: Revisiting the CO-H2 Conversion Factor Tension
Prachi Prajapati, Axel Weiss, Dominik Riechers, Tom J. L. C. Bakx, Leindert A. Boogaard, Diana Ismail, Pierre Cox, Andrew J. Baker, Roberto Neri, Matthew Lehnert, Chentao Yang, Emilio Romano-Diaz, Hiddo S. B. Algera, Stefano Berta, Edoardo Borsato, Kirsty M. Butler, Asantha Cooray, Bethany Jones, Amelie Saintonge, Paul van der Werf
https://arxiv.org/abs/2607.18440 https://arxiv.org/pdf/2607.18440 https://arxiv.org/html/2607.18440
arXiv:2607.18440v1 Announce Type: new
Abstract: The CO luminosity-to-H$_2$ mass conversion factor ($\alpha_{CO}$) remains a debated uncertainty in determining molecular gas masses of high-redshift dusty star-forming galaxies (DSFGs). Dynamical mass constraints have often favored $\alpha_{CO}=0.8$~$M_{\odot}~{(K~km~{s}^{-1}~{pc}^{2})}^{-1}$, whereas dust- and radiative-transfer-based methods imply higher values. We revisit this ``tension" using the largest homogeneous sample of 21 unlensed $z\sim1-4$ DSFGs, with securely measured \coonezero luminosities from the VLA \vzgal survey and resolved ($\sim{0.1}^{\prime\prime}$) ALMA 1~mm dust continuum imaging. For 12 galaxies with robust modeling constraints, we derive molecular gas masses using dust spectral energy distribution modeling and the TUNER LVG framework, adopting a solar-metallicity gas-to-dust mass ratio of 100. Although not fully independent due to shared assumptions on dust properties, these approaches yield mutually consistent gas masses corresponding to $\alpha_{CO}\sim1.5-11.5$, with a median near the Galactic $\alpha_{CO}=4.3$. Isotropic virial dynamical masses agree with these gas masses when realistic molecular gas sizes are adopted, while our proposed ``mixed" (rotating, pressure-supported, thick-disk) estimator systematically underestimates dynamical masses, producing low $\alpha_{CO}$ limits. Using GN20 ($z=4.055$) as a case study, we show that resolved gas geometry and kinematics reconcile the discrepancy with LVG-derived $\alpha_{CO}$. Our results suggest that current data do not require $\alpha_{CO}=0.8$, and intermediate to near-Galactic values remain dynamically viable given uncertainties in gas geometry, dust properties, and gas-to-dust ratios. Further progress in calibrating $\alpha_{CO}$ in the early universe will require resolved molecular gas observations, physically motivated ISM modeling, and stringent constraints on dust properties.
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A black hole in a near pristine galaxy 700 Myr after the big bang / A direct black-hole mass measurement in a #LittleRedDot at high redshift: https://academic.oup.com/mnras/article/548/1/staf2109/8607050?login=false / https://www.nature.com/articles/s41586-026-10579-4 -> Webb reveals black hole that formed before its galaxy: https://esawebb.org/news/weic2609/ and https://science.nasa.gov/missions/webb/nasas-webb-reveals-black-hole-that-formed-before-its-galaxy/ - the first direct mass measurement from the early Universe weighs in on the debate over the origins of supermassive black holes.
An (in)complete NIRSpec census of Balmer absorption in Type 1 AGN -- radiation-driven outflows in little red dots, quasars and variable stars
Ignas Juod\v{z}balis, Xihan Ji, Francesco D'Eugenio, Jan Scholtz, Roberto Maiolino, Amanda Stoffers, Alessandro Marconi, Elena Bertola, Andrew J. Bunker, Stefano Carniani, Giovanni Cresci, Emma Curtis-Lake, Zheng Ma, Cosimo Marconcini, Eleonora Parlanti, Pierluigi Rinaldi, Brant Robertson, Hannah \"Ubler, Giacomo Venturi, Junyu Zhang
https://arxiv.org/abs/2607.19057 https://arxiv.org/pdf/2607.19057 https://arxiv.org/html/2607.19057
arXiv:2607.19057v1 Announce Type: new
Abstract: A notable achievement of the first generation of JWST surveys was the discovery of an abundance of faint high-redshift ($z > 4$) broad-line active galactic nuclei (AGN) in the $L_{\rm bol} < 10^{45}$~erg~s$^{-1}$ regime, previously only accessible at $z < 1$. The high prevalence of absorption features in their broad hydrogen lines is one of the peculiarities of a significant fraction of this new population. In this paper, we conduct a broad census of Balmer absorption in a sample of 47 Type-1 AGN spanning $2 < z < 7$. Accounting for incompleteness of JWST spectroscopic data, we estimate that $44_{-6}^{ 21}$~\% of Little Red Dots (LRDs) have absorption in \Has while the incidence rate is $< 25$~\% (at 2$\sigma$) in Little Blue Dots (LBDs). Additionally, R1000 JWST/NIRSpec data is strongly resolution limited, implying an inability to disentangle Doppler broadening in the absorption from optical depth effects. This is alleviated with R2700 observations, although some degeneracies remain. We find a significant correlation between the velocity of the Balmer absorption and the [OIII]5007 narrow line luminosity, suggesting a common driving mechanism. We do not find any other significant correlations (and do not confirm previously claimed correlations) between Balmer absorption and other spectral properties of LRDs (except for the expected correlation between \Has and \Hbs absorption velocities). Comparing LRDs, quasars and stellar \Has absorbers, we establish that absorption in both LRDs and broad absorption line quasars is consistent with radiatively driven outflows, echoing the physics of variable stars yet occurring at vastly different scales.
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Bright Galaxies at Cosmic Dawn: A Cloud-Scale Star Formation Model Unifying Variable SFE, IMFs, and Stochasticity
Elie Cueto, Anne Hutter
https://arxiv.org/abs/2607.18868 https://arxiv.org/pdf/2607.18868 https://arxiv.org/html/2607.18868
arXiv:2607.18868v1 Announce Type: new
Abstract: To investigate the origins of the high abundance of UV-bright galaxies at z > 10, we present a new semi-analytic model that bridges the gap between small-scale star formation physics and large-scale galaxy evolution by explicitly tracking discrete star-forming clouds within smoothly evolving dark matter potentials. Unlike conventional semi-analytic models, our approach naturally captures the stochasticity of star formation, allowing us to isolate how cloud properties, star formation efficiencies (SFEs), and stellar initial mass functions (IMFs) shape the star-formation burstiness of early galaxies. Clouds are drawn sequentially from a cloud mass distribution, assigned an SFE and IMF depending on cloud mass, metallicity, and redshift, and evolve under the influence of short-timescale stellar feedback. We identify three distinct star formation regimes arising from the interplay between cloud masses, densities, and feedback timescales: a stochastic, feedback-limited regime in low-mass halos with long quiescent phases; a bursty regime regulated by the cloud mass distribution; and a smooth, continuous regime in massive halos. Our fiducial model adopts a dynamic IMF, an SFE linked to cloud properties and the IMF, and massive, moderately dense clouds. Varying assumptions reveals that top-heavy IMFs and enhanced SFEs in massive clouds amplify burstiness, while altering the upper cloud mass or density normalisation is secondary. Among model ingredients, the IMF most strongly impacts the UV luminosity function (LF), while switching to a constant SFE boosts the faint end, and reducing the maximum cloud mass decreases the bright end. These results demonstrate that cloud-scale physics critically shape early galaxy UV luminosity distributions.
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Physical Properties of 6.7 Million Galaxies from the DESI Bright Galaxy Survey: Spectral Fitting and Systematic Tests with Mock Spectra
Niu Li, Hu Zou, Jinfu Gou, Weijian Guo, Wenxiong L, Haoming Song, Jipeng Sui, Xi Tan, Yunao Xiao, Jingyi Zhang
https://arxiv.org/abs/2607.19162 https://arxiv.org/pdf/2607.19162 https://arxiv.org/html/2607.19162
arXiv:2607.19162v1 Announce Type: new
Abstract: We present a comprehensive analysis of the physical properties of galaxies in the Dark Energy Spectroscopic Instrument (DESI) Data Release 1 (DR1) Bright Galaxy Survey (BGS), based on full spectral fitting of $\sim 6.7$ million galaxy spectra. Using a customized spectral fitting pipeline, we derive key physical parameters including stellar mass, stellar velocity dispersion, stellar population age, dust attenuation, and emission-line properties. To quantify the reliability and systematic uncertainties of our measurements, we construct a large set of mock spectra that closely reproduce the observed properties of DESI data, including realistic noise and spectral features. By comparing the recovered parameters with the known inputs, we assess the performance of the spectral fitting as a function of stellar continuum signal-to-noise ratio (S/N, defined as the ratio of the median continuum flux to its associated error) and redshift. We find that stellar masses can be robustly recovered with negligible bias for spectra with $\mathrm{S/N} \gtrsim 5$, while low-S/N spectra ($\mathrm{S/N} \lesssim 5$) show a mild systematic overestimation of $\sim 0.1$ dex and increased scatter. Similar trends are observed for stellar population parameters, while emission-line fluxes are recovered with high accuracy and minimal bias. We further validate our stellar mass estimates by comparison with independent measurements from photometric spectral energy distribution fitting, finding good overall consistency within the expected systematic uncertainties. The value-added catalog presented in this work enables a wide range of statistical studies of galaxy evolution with DESI, and provides a foundation for future analyses.
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Replaced article(s) found for astro-ph.GA. https://arxiv.org/list/astro-ph.GA/new
[1/3]:
- CO Observations of Early-mid Stage Major Mergers in the MaNGA Survey
Yu, Fang, Xu, Feng, Feng, Gao, Jiang, Lisenfeld
https://arxiv.org/abs/2404.18999 https://mastoxiv.page/@arXiv_astrophGA_bot/112364597912941989
- A first systematic study of [OIII] 88$\mu$m at $z>8$: two luminous oxygen lines and a powerful io...
Hiddo S. B. Algera, et al.
https://arxiv.org/abs/2512.14486 https://mastoxiv.page/@arXiv_astrophGA_bot/115734347184965000
- Electron temperature relations and the direct N, O, Ne, S and Ar abundances of 49959 star-forming...
D. Scholte, et al.
https://arxiv.org/abs/2601.02463 https://mastoxiv.page/@arXiv_astrophGA_bot/115852861581257007
- The Role of Inner Halo Angular Momentum (Spin) in Shaping Dark Matter Bars in Milky Way Analogs
Shouvik Ghosh, Sandeep Kumar Kataria
https://arxiv.org/abs/2601.14420 https://mastoxiv.page/@arXiv_astrophGA_bot/115938036617000433
- GA-NIFS: Dissecting The Alchemised: JWST reveals turbulent metal-poor gas fuelling a co-spatial s...
Robert G. Pascalau, et al.
https://arxiv.org/abs/2603.00232 https://mastoxiv.page/@arXiv_astrophGA_bot/116164296791419745
- The Star Formation History of WLM from Asymptotic Giant Branch Stars and The Discovery of a Candi...
Abigail J. Lee, Daniel R. Weisz, Andrew E. Dolphin, Alessandro Savino
https://arxiv.org/abs/2603.00243 https://mastoxiv.page/@arXiv_astrophGA_bot/116164584608441374
- Two Exciting High-redshift Galaxy Candidates Turn Out to Be Two Exciting Ultra-cool Brown Dwarfs
Maru\v{s}a Brada\v{c}, et al.
https://arxiv.org/abs/2604.23668 https://mastoxiv.page/@arXiv_astrophGA_bot/116481375281380996
- PEARLS: JWST Counterparts of Micro-Jy Radio Sources in the NEP Time Domain Field. II. All Four Sp...
S. P. Willner, et al.
https://arxiv.org/abs/2605.17040 https://mastoxiv.page/@arXiv_astrophGA_bot/116600246884579228
- Eppur non si trovano Vol. 3: Phoebe -- a Mirage of a Primordial Black Hole
Andrzej Udalski, Przemek Mr\'oz
https://arxiv.org/abs/2606.19442 https://mastoxiv.page/@arXiv_astrophGA_bot/116775643602203820
- LEGGOS I: The JWST LEGGOS Survey -- LEnsing and Galaxy Growth: Observing Substructures -- Unpacks...
Gourav Khullar, et al.
https://arxiv.org/abs/2606.20845 https://mastoxiv.page/@arXiv_astrophGA_bot/116798485365000724
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