Results 61 to 70 of about 49,283 (254)

The Evolution of the Galaxy Cluster Luminosity-Temperature Relation

, 2002
We analyzed the luminosity-temperature (L-T) relation for 2 samples of galaxy clusters which have all been observed by the ASCA satellite.
J. Patrick Henry, Kaiser N., Manuela Sornig, Megan C. Novicki, Sadat R., White D. A.   +5 more
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

Spectroscopic Confirmation of a Massive Protocluster with Two Substructures at z ≃ 3.1

The Astrophysical Journal
We present the results of a Keck and Northern Extended Millimeter Array spectroscopic survey of 507 galaxies, where we confirm the presence of two massive overdensities at z = 3.090−3.110 and z = 3.133−3.155 in the neighborhood of the GOODS-N, each with ...
Michael J. Nicandro Rosenthal, Amy J. Barger, Lennox L. Cowie, Logan H. Jones, Stephen J. McKay, Anthony J. Taylor   +5 more
doaj   +1 more source

The NIKA2 Sunyaev-Zeldovich Large Program [PDF]

EPJ Web of Conferences
The NIKA2 camera operating at the IRAM 30-m telescope excels in high-angular resolution mapping of the thermal Sunyaev-Zel’dovich effect towards galaxy clusters at intermediate and high-redshift. As part of the NIKA2 guaranteed-time, the SZ Large Program
Perotto L., Adam R., Ade P., Ajeddig H., André P., Artis E., Aussel H., Barrena R., Bartalucci I., Beelen A., Benoît A., Berta S., Bing L., Bourrion O., Calvo M., Catalano A., De Petris M., Désert F.-X., Doyle S., Driessen E. F. C., Ejlali G., Ferragamo A., Gomez A., Goupy J., Hanser C., Katsioli S., Kéruzoré F., Kramer C., Ladjelate B., Lagache G., Leclercq S., Lestrade J.-F., Macías-Pérez J.F., Madden S. C., Maury A., Mauskopf P., Mayet F., Monfardini A., Moyer-Anin A., Muñoz-Echeverría M., Paliwal A., Pisano G., Pointecouteau E., Ponthieu N., Pratt G.W., Revéret V., Rigby A. J., Ritacco A., Romero C., Roussel H., Ruppin F., Schuster K., Sievers A., Tucker C., Yepes G.   +54 more
doaj   +1 more source

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

MAGAZ3NE: Evidence for Galactic Conformity in z ≳ 3 Protoclusters

The Astrophysical Journal
We examine the quiescent fractions of massive galaxies in six z ≳ 3 spectroscopically confirmed protoclusters in the COSMOS field, one of which is newly confirmed and presented here. We report the spectroscopic confirmation of MAGAZ3NE J100143+023021 at $
Ian McConachie, Gillian Wilson, Ben Forrest, Z. Cemile Marsan, Adam Muzzin, M. C. Cooper, Marianna Annunziatella, Danilo Marchesini, Percy Gomez, Wenjun Chang, Stephanie M. Urbano Stawinski, Michael McDonald, Tracy Webb, Allison Noble, Brian C. Lemaux, Ekta A. Shah, Priti Staab, Lori M. Lubin, Roy R. Gal   +18 more
doaj   +1 more source

Redshift Evolution of the Feedback–Cooling Equilibrium in the Core of 48 SPT Galaxy Clusters: A Joint Chandra–SPT–ATCA Analysis

The Astrophysical Journal, 2023
We analyze the cooling and feedback properties of 48 galaxy clusters at redshifts 0.4 < z < 1.3 selected from the South Pole Telescope (SPT) catalogs to evolve like the progenitors of massive and well-studied systems at z ∼ 0. We estimate the radio power
F. Ruppin, M. McDonald, J. Hlavacek-Larrondo, M. Bayliss, L. E. Bleem, M. Calzadilla, A. C. Edge, M. D. Filipović, B. Floyd, G. Garmire, G. Khullar, K. J. Kim, R. Kraft, G. Mahler, R. P. Norris, A. O’Brien, C. L. Reichardt, T. Somboonpanyakul, A. A. Stark, N. Tothill   +19 more
doaj   +1 more source

Hierarchical Clustering and the Butcher-Oemler Effect

, 1994
We show that the rapid evolution in the fraction of blue, star-forming galaxies seen in clusters as a function of redshift (the Butcher-Oemler effect) can be explained very simply if structure formation in the universe proceeeds hierarchically.
Kauffmann, Guinevere
core   +2 more sources

The Radio Luminosity Function of Cluster Radio Halos [PDF]

, 2002
A significant fraction of galaxy clusters exhibits cluster wide radio halos. We give a simple prediction of the local and higher redshift radio halo luminosity function (RHLF) on the basis of (i) an observed and a theoretical X-ray cluster luminosity ...
Ensslin, Torsten A., Roettgering, Huub
core   +3 more sources

Galaxy colours in high-redshift, X-ray-selected clusters - I. Blue galaxy fractions in eight clusters [PDF]

Monthly Notices of the Royal Astronomical Society, 2002
We present initial results from a wide-field, multi-colour imaging project, designed to study galaxy evolution in X-ray selected clusters at intermediate (z~0.25) and high redshifts (z~0.5). In this paper we give blue galaxy fractions from eight X-ray selected clusters, drawn from a combined sample of three X-ray surveys.
Fairley, B. W., Jones, L. R., Wake, D. A., Collins, C. A., Burke, D. J., Nichol, R. C., Romer, A. K.   +6 more
openaire   +4 more sources