Results 91 to 100 of about 108,043 (278)

Low-redshift Analogs of Cosmic Noon Galaxies as Laboratories for Clumpy Star Formation

The Astrophysical Journal
It has been established that a significant fraction of star formation at high redshift occurs in clumpy galaxies. The properties of clumps and their formation mechanisms, however, remain highly debated. In this work we analyze a sample of 18 supercompact
Jorge M. Santos-Junior, Thiago S. Gonçalves, Luidhy Santana-Silva, Arianna Cortesi, Karin Menendez-Delmestre, Amanda E. Araujo-Carvalho   +5 more
doaj   +1 more source

DUST ATTENUATION IN HIGH REDSHIFT GALAXIES: “DIAMONDS IN THE SKY” [PDF]

, 2014
We use observed optical to near-infrared spectral energy distributions (SEDs) of 266 galaxies in the COSMOS survey to derive the wavelength dependence of the dust attenuation at high redshift. All of the galaxies have spectroscopic redshifts in the range
N. Scoville, A. Faisst, P. Capak, Y. Kakazu, Gongjie Li, C. Steinhardt   +5 more
semanticscholar   +1 more source

Very High-Redshift Lensed Galaxies [PDF]

Proceedings of the International Astronomical Union, 2004
We review in this paper the main results recently obtained on the identification and study of very high-z galaxies usinglensing clusters as natural gravitational telescopes. We present in detail our pilot survey with ISAAC/VLT, aimed at the detection of z>7 sources.
Pelló, R., Schaerer, D., Richard, J., Le Borgne, J.-F., Kneib, J.-P.   +4 more
openaire   +3 more sources

Redshift‐Agnostic Machine Learning Classification: Unveiling Peak Performance in Galaxy, Star, and Quasar Classification (Using SDSS DR17)

Astronomische Nachrichten, Volume 346, Issue 5, June 2025.
ABSTRACT Classification of galaxies, stars, and quasars using spectral data is fundamental to astronomy, but often relies heavily on redshift. This study evaluates the performance of 10 machine learning algorithms on SDSS data to classify these objects, with a particular focus on scenarios where redshift information is unavailable.
Debashis Chatterjee, Prithwish Ghosh
wiley   +1 more source

Early Results from GLASS-JWST. XXV. Electron Density in the Interstellar Medium at 0.7 ≲ z ≲ 9.3 with NIRSpec High-resolution Spectroscopy

The Astrophysical Journal Letters
The electron density ( n _e ) of the interstellar medium (ISM) in star-forming galaxies is intimately linked to star formation and ionization condition.
Sijia Li, Xin Wang, Yuguang Chen, Tucker Jones, Tommaso Treu, Karl Glazebrook, Xianlong He, Alaina Henry, Xiao-Lei Meng, Takahiro Morishita, Guido Roberts-Borsani, Lilan Yang, Hao-Ran Yu, Antonello Calabrò, Marco Castellano, Nicha Leethochawalit, Benjamin Metha, Themiya Nanayakkara, Namrata Roy, Benedetta Vulcani   +19 more
doaj   +1 more source

CONSTRAINTS ON PHOTOIONIZATION FEEDBACK FROM NUMBER COUNTS OF ULTRA-FAINT HIGH-REDSHIFT GALAXIES IN THE FRONTIER FIELDS [PDF]

, 2014
We exploit a sample of ultra-faint high-redshift galaxies (demagnified Hubble Space Telescope, HST, H160 magnitude > 30) in the Frontier Fields clusters A2744 and M0416 to constrain a theoretical model for the UV luminosity function in the presence of ...
B. Yue, Andrea Ferrara, E. Vanzella, R. Salvaterra   +3 more
semanticscholar   +1 more source

Lactea: Web‐Based Spectrum‐Preserving Multi‐Resolution Visualization of the GAIA Star Catalog

Computer Graphics Forum, Volume 44, Issue 3, June 2025.
Abstract The explosion of data in astronomy has resulted in an era of unprecedented opportunities for discovery. The GAIA mission's catalog, containing a large number of light sources (mostly stars) with several parameters such as sky position and proper motion, is playing a significant role in advancing astronomy research and has been crucial in ...
Reem Alghamdi, Markus Hadwiger, Guido Reina, Alberto Jaspe‐Villanueva   +3 more
wiley   +1 more source

A PHYSICAL MODEL FOR THE EVOLVING ULTRAVIOLET LUMINOSITY FUNCTION OF HIGH REDSHIFT GALAXIES AND THEIR CONTRIBUTION TO THE COSMIC REIONIZATION [PDF]

, 2014
We present a physical model for the evolution of the ultraviolet (UV) luminosity function of high-redshift galaxies, taking into account in a self-consistent way their chemical evolution and the associated evolution of dust extinction. Dust extinction is
Z. Cai, A. Lapi, A. Bressan, G. De Zotti, M. Negrello, L. Danese   +5 more
semanticscholar   +1 more source

Dark Energy From the Gravitational Wave Background With Scalar Field Dark Matter

Astronomische Nachrichten, Volume 346, Issue 3-4, March-May 2025.
ABSTRACT Recent observational results, such as those from pulsar timing arrays (PTA), suggest a low‐frequency Gravitational Wave Background (GWB) permeates our universe. This opens the possibility that gravitational waves could span a broader spectrum, potentially impacting cosmological scales.
Edwin L. Pérez‐Ochoa, Tonatiuh Matos
wiley   +1 more source

CHILES. XI. Resolved H I Morphologies and the Evolution of the H2/H I Ratio over the Last Five Billion Years

The Astrophysical Journal
We present the neutral gas morphology of four galaxies from z = 0.22 to 0.47 obtained with the COSMOS H i Large Extragalactic Survey (CHILES). The H i is resolved at the highest redshift with the 7 $\mathop{.}\limits^{\unicode{x02033}}$ 5 beam of CHILES ...
J. Blue Bird, N. Luber, H. B. Gim, J. H. van Gorkom, D. J. Pisano, Min S. Yun, E. Momjian, K. M. Hess, D. Lucero, J. Donovan Meyer, A. Chung   +10 more
doaj   +1 more source