English

Galaxy cluster mass density profile derived using the submillimetre galaxies magnification bias

Cosmology and Nongalactic Astrophysics 2022-01-26 v1 Astrophysics of Galaxies

Abstract

In this work we want to study the average mass density profile of tens to hundreds of clusters of galaxies acting as lenses that produce a magnification bias on the SMGs, and to estimate their associated masses and concentrations for different richness ranges. The background sample is composed of SMGs observed by Herschel with 1.2<z<4.0 (mean redshift at ~2.3) while the foreground sample is made up of galaxy clusters extracted from the SDSS III with photometric redshifts of 0.05< z< 0.8 (mean redshift at ~0.38). Measurements are obtained by stacking the SMG--cluster pairs to estimate the cross-correlation function using the Davis-Peebles estimator. This methodology allows us to derive the mass density profile for a wide range of angular scales, ~2-250 arcsec or ~10-1300 kpc for z=0.38, with a high radial resolution. We find that It is impossible to fit the data with a single mass density profile at all scales. As for the outer part, the estimated average masses increase from M200c=5.8M_{200c}=5.8 to 51.5×1013M51.5\times 10^{13} M_\odot and the concentration parameter from C=0.74 to 1.74. In the small-scale regions, the obtained average masses fluctuate around M200c=34×1013MM_{200c}=3-4 \times 10^{13}M_\odot with average C~4. The total average masses are in perfect agreement with the M-R relationship estimated from the cluster catalogue. While the estimated average C values of the central galactic halos are in agreement with traditional M-C relationships, we find low concentrations for the outer part. Moreover, C decrease for lower R values, probably indicating that the group of galaxies cannot be considered to be relaxed systems. Finally, we notice a systematic lack of signal at the transition between the dominance of the cluster halo and the central galactic halo (~100 kpc). This feature is also present in previous studies using different catalogues and/or methodologies, but is never discussed.

Keywords

Cite

@article{arxiv.2111.05422,
  title  = {Galaxy cluster mass density profile derived using the submillimetre galaxies magnification bias},
  author = {L. Fernandez and M. M. Cueli and J. González-Nuevo and L. Bonavera and D. Crespo and J. M. Casas and A. Lapi},
  journal= {arXiv preprint arXiv:2111.05422},
  year   = {2022}
}

Comments

12 pages, 6 figures, accepted for publication by A&A