Results 91 to 100 of about 14,841,931 (226)

Late-time growth weakly affects the significance of high-redshift massive galaxies

The Open Journal of Astrophysics
Recent observations by the James Webb Space Telescope have revealed massive galaxies at very high redshift ($z\simeq 7-15$). The question of whether the existence of such galaxies is expected in the corresponding JWST surveys has received a lot of ...
Qianran Xia, Dragan Huterer, Nhat-Minh Nguyen   +2 more
doaj   +1 more source

UV–Vis Spectra of Carbonic Acid: Rationalizing Experimental Redshifts between Monomer and Bulk based on (H2CO3)n Calculations

ChemPhysChem, Volume 26, Issue 18, September 19, 2025.
In bulk carbonic acid (e.g., in interstellar icy dust grains) cluster formation produces two distinct UV‐Vis spectral features redshifted by ≈2 eV (25 nm) and by ≈5 eV (80 nm) compared to gas phase single molecule carbonic acid 's adiabatic ionization energy. Theory and experiment were used to investigate the origin of these shifts.
Dennis F. Dinu, Bastian Klein, Chaojiang Zhang, Radu A. Talmazan, Thomas Loerting, Hinrich Grothe, Ralf I. Kaiser, Maren Podewitz   +7 more
wiley   +1 more source

High‐Redshift Galaxy Outflows and the Formation of Dwarf Galaxies

The Astrophysical Journal, 2001
15 pages, 9 figures, accepted to the Astrophysical ...
Scannapieco, Evan, Thacker, Robert J., Davis, Marc   +2 more
openaire   +2 more sources

A complete redshift sample of galaxies [PDF]

, 1983
The role of complete redshift samples is discussed with particular attention focused on the need for new deeper and better controlled surveys for statistical clustering and dynamical studies.
Bean, A.J., Bean, Adrian John
core  

Integral-Field Spectroscopy of High-Redshift Galaxies: Implications for Early Galaxy Evolution [PDF]

, 2006
Several lines of evidence suggest that the most active phase of galaxy evolution, especially in the most massive systems, was largely completed by $z\sim 1$.
Nesvadba, Nicole
core   +1 more source

Two Micron‐Size Dark Dimensions

Fortschritte der Physik, Volume 73, Issue 8, August 2025.
Abstract Two extra dimensions of micron scale might simultaneously address the gauge and cosmological hierarchy problems. In this paper various observational bounds in scenarios with one and two large extra dimensions are examined, to see if they are compatible with the micron scale.
Luis A. Anchordoqui, Ignatios Antoniadis, Dieter Lüst   +2 more
wiley   +1 more source

Exploring the star formation histories of galaxies [PDF]

, 1999
In this thesis, I explore the star formation histories of both spiral and elliptical galaxies. In Part 1,1 present an in-depth study of the star formation histories of spiral galaxies with a wide range of properties. Optical and near-infrared colours are
Bell, Eric Findlay, Bell, E.F.
core  

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

JADES: The Star Formation and Dust Reddening Properties of Galaxies at 3 < z < 7

The Astrophysical Journal
We present the star formation and dust content properties for a sample of 646 galaxies at redshifts 3 
Charity Woodrum, Irene Shivaei, Joris Witstok, Aayush Saxena, Charlotte Simmonds, Jan Scholtz, Rachana Bhatawdekar, Andrew J. Bunker, Stefano Carniani, Stéphane Charlot, Mirko Curti, Emma Curtis-Lake, Jacopo Chevallard, Francesco D’Eugenio, Kevin Hainline, Jakob M. Helton, Roberto Maiolino, Michele Perna, Pierluigi Rinaldi, Brant Robertson, Amber Straughn, Yang Sun, Sandro Tacchella, Christina C. Williams, Chris Willott, Yongda Zhu, Ana Varo O’Ferrall   +26 more
doaj   +1 more source

Tracing nitrogen enrichment across cosmic time with JWST

Astronomy & Astrophysics
We present a comprehensive analysis of the nitrogen-to-oxygen (N/O) abundance ratio in a sample of ∼660 star-forming galaxies at redshift z ∼ 1 − 6, with a median redshift of ⟨z⟩ = 3.0, using deep JWST/NIRSpec spectroscopy. Leveraging detections of faint
Cataldi E., Belfiore F., Curti M., Moreschini B., Marconi A., Maiolino R., Feltre A., Ginolfi M., Mannucci F., Cresci G., Ji X., Amiri A., Arnaboldi M., Bertola E., Bracci C., Ceci M., Chakraborty A., Cullen F., D’Amato Q., Kobayashi C., Lamperti I., Marconcini C., Scialpi M., Ulivi L., Zanchettin M. V.   +24 more
doaj   +1 more source