Results 61 to 70 of about 5,210 (169)
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 +2 more
wiley +1 more source
A study of the core of the Shapley Concentration — IV. Distribution of intercluster galaxies and supercluster properties [PDF]
, 1999 We present the results of a redshift survey of intercluster galaxies in the central region of the Shapley Concentration supercluster, aimed at determining the distribution of galaxies in between obvious overdensities.
S. Bardelli +4 more
semanticscholar +1 more source
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
A complete census of circumgalactic Mg ii at redshift z ≲ 0.5
, 2021 We present a survey of MgII absorbing gas in the vicinity of 380 random galaxies, using 156 background quasi-stellar objects(QSOs) as absorption-line probes.
Yun-Hsin Huang +7 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 +3 more
wiley +1 more source
Astronomy & AstrophysicsContext. Strong-lensing systems are expected to be discovered in great numbers by next-generation surveys. They provide a powerful tool for studying cosmology and the galaxy evolution. The coupling of the galaxy structure and cosmology through distance ratios means that it is essential for advancing both fields to examine the evolution of the lensing ...
S. Geng +5 more
openaire +2 more sources
The Astrophysical Journal, 2006 ApJ submitted (revised version)
Bonamente, M. +5 more
openaire +2 more sources
Towards a precision cosmology from starburst galaxies at z > 2 [PDF]
, 2004 This work investigates the use of a well-known empirical correlation between the velocity dispersion, metallicity and luminosity in Hβ of nearby H II galaxies to measure the distances to H II-like starburst galaxies at high redshifts. This correlation is
E. Siegel +4 more
semanticscholar +1 more source
Engineering Reports, Volume 7, Issue 3, March 2025.We present the details of implementing a highly efficient and scalable Cosmological N‐body simulation framework on the heterogeneous many‐core supercomputer Sunway TaihuLight. We manage to conduct cosmological simulations which contain up to 1.6 trillion particles, obtaining a sustained performance of 56.3 PFlops with a weak‐scaling parallel efficiency
Zhao Liu +8 more
wiley +1 more source
Radial and Transverse Velocities of Nearby Galaxies [PDF]
, 2000 Analysis of the peculiar velocities of the galaxies should take account of the uncertainties in both redshifts and distances. We show how this can be done by a numerical application of the action principle. The method is applied to an improved catalog of
P. J. Peebles +3 more
semanticscholar +1 more source