Saved in:
Bibliographic Details
Main Authors: Abdullah, Mohamed H., Samir, Rasha M., Abdelhamid, Nouran E., Abdulshafy, Shrouk, Wilson, Gillian, Klypin, Anatoly, Shehata, SH. M., Shaker, Ashraf A.
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2603.14330
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910053729042432
author Abdullah, Mohamed H.
Samir, Rasha M.
Abdelhamid, Nouran E.
Abdulshafy, Shrouk
Wilson, Gillian
Klypin, Anatoly
Shehata, SH. M.
Shaker, Ashraf A.
author_facet Abdullah, Mohamed H.
Samir, Rasha M.
Abdelhamid, Nouran E.
Abdulshafy, Shrouk
Wilson, Gillian
Klypin, Anatoly
Shehata, SH. M.
Shaker, Ashraf A.
contents The stellar-to-halo mass (SMHM) relation of brightest cluster galaxies (BCGs) provides key insight into the connection between BCG growth and the assembly of their host halos. We analyze this relation using the spectroscopic SDSS GalWCat19 cluster catalog, selecting 996 systems with log(M200) >= 13.6, log(Mstar) >= 10.5, and 0.02 <= z <= 0.125 to limit evolutionary effects and ensure stellar-mass completeness. We fit lognormal scaling relations with a Markov Chain Monte Carlo (MCMC) framework that accounts for measurement uncertainties and intrinsic scatter. For the fiducial SMHM relation, <log Mstar | M200> = alpha + beta log(M200/Mpiv) with log(Mpiv) = 14.2, we find a shallow slope beta = 0.17 +/- 0.03, normalization alpha = 11.04 +/- 0.01, and intrinsic scatter sigma_int = 0.19 +/- 0.01 dex. Recasting the relation in normalized form reduces the scatter to 0.16 +/- 0.01 dex, while including the magnitude gap M14 further reduces it to 0.14 +/- 0.01 dex. Variations in richness, redshift, and mass thresholds produce systematic shifts that are small compared to the statistical uncertainties, indicating that our inferred relations are robust to plausible selection choices. The reduced scatter when including M14 supports a picture in which BCG stellar mass reflects both halo mass and halo assembly history.
format Preprint
id arxiv_https___arxiv_org_abs_2603_14330
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Hidden Connections: Tracing the BCG Stellar Mass-Halo Mass Relation in the SDSS-GalWCat19 Cluster Catalog
Abdullah, Mohamed H.
Samir, Rasha M.
Abdelhamid, Nouran E.
Abdulshafy, Shrouk
Wilson, Gillian
Klypin, Anatoly
Shehata, SH. M.
Shaker, Ashraf A.
Astrophysics of Galaxies
The stellar-to-halo mass (SMHM) relation of brightest cluster galaxies (BCGs) provides key insight into the connection between BCG growth and the assembly of their host halos. We analyze this relation using the spectroscopic SDSS GalWCat19 cluster catalog, selecting 996 systems with log(M200) >= 13.6, log(Mstar) >= 10.5, and 0.02 <= z <= 0.125 to limit evolutionary effects and ensure stellar-mass completeness. We fit lognormal scaling relations with a Markov Chain Monte Carlo (MCMC) framework that accounts for measurement uncertainties and intrinsic scatter. For the fiducial SMHM relation, <log Mstar | M200> = alpha + beta log(M200/Mpiv) with log(Mpiv) = 14.2, we find a shallow slope beta = 0.17 +/- 0.03, normalization alpha = 11.04 +/- 0.01, and intrinsic scatter sigma_int = 0.19 +/- 0.01 dex. Recasting the relation in normalized form reduces the scatter to 0.16 +/- 0.01 dex, while including the magnitude gap M14 further reduces it to 0.14 +/- 0.01 dex. Variations in richness, redshift, and mass thresholds produce systematic shifts that are small compared to the statistical uncertainties, indicating that our inferred relations are robust to plausible selection choices. The reduced scatter when including M14 supports a picture in which BCG stellar mass reflects both halo mass and halo assembly history.
title Hidden Connections: Tracing the BCG Stellar Mass-Halo Mass Relation in the SDSS-GalWCat19 Cluster Catalog
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2603.14330