X-ray properties of the X-CLASS-redMaPPer galaxy cluster sample: the luminosity–temperature relation

Abstract

This article presents the results of a spectroscopic analysis of the X-CLASS-redMaPPer (XC1-RM) galaxy cluster sample. X-CLASS is a serendipitous search for clusters in X-ray wavebands based on the XMM–Newton archive, whereas redMaPPer is an optical cluster catalogue derived from the Sloan Digital Sky Survey (SDSS). The present sample comprises 92 X-ray extended sources identified in optical images within 1 arcmin separation. The area covered by the cluster sample is ∼ 27 deg2. The clusters span a wide redshift range (0.05 < z < 0.6) and 88 clusters benefit from spectrosopically confirmed redshifts using data from SDSS Data Release 14. We present an automated pipeline to derive the X-ray properties of the clusters in three distinct apertures: R500 (at fixed mass overdensity), Rfit (at fixed signal-to-noise ratio) and ${R}_{300\, {\rm kpc}}$ (fixed physical radius). The sample extends over wide temperature and luminosity ranges: from 1–10 keV and from 6 × 1042 to 11 × 1044 erg s−1, respectively. We investigate the luminosity–temperature (L–T) relation of the XC1-RM sample and find a slope equal to 3.03 ± 0.26. It is steeper than predicted by self-similar assumptions, in agreement with independent studies. A simplified approach is developed to estimate the amount and impact of selection biases that might be affecting our recoveredL–Tparameters. The result of this simulation process suggests that the measuredL–Trelation is biased to a steeper slope and higher normalization.

Cosmological Simulation of Galaxy Groups and Clusters. II. Studying Different Modes of Feedback through X-Ray Observations

“…Enormous amounts of energy released by a fraction of the SMBH population, in the form of radiative winds, energetic jets, and other mechanisms (Fabian 2012;King & Pounds 2015;Harrison et al 2018;Roy et al 2021), influence several properties of the SMBH host galaxies (e.g., Dressler & Richstone 1988;Kauffmann & Haehnelt 2000;Ferrarese & Merritt 2000;Gebhardt et al 2000;Graham et al 2001;Häring & Rix 2004;Cattaneo et al 2009;Kormendy & Ho 2013;Salviander et al 2015;Fiore et al 2017;Mutlu-Pakdil et al 2018;Schutte et al 2019;de Nicola et al 2019;Marsden et al 2020). Some of the other signatures of AGN feedback involve: a reduced star formation rate in host galaxies (e.g., Vitale et al 2013;Costa et al 2015;Harrison 2017), the absence of cooling flows (e.g., David et al 2001;Peterson et al 2003), or the change in slope of the L X -T relation in galaxy clusters and groups (e.g., Andersson et al 2009;Maughan et al 2012;Molham et al 2020). Despite these series of observational results, a full theoretical understanding of how the energy released from the black hole couples to its surrounding medium, a phenomenon termed active galactic nuclei (AGN) feedback, is yet to arise (e.g., Silk & Rees 1998;Nath & Roychowdhury 2002;Fabian 2012;Li et al 2018;Heinrich et al 2021).…”

Scaling relations of X-ray Luminous Clusters in the Hyper Suprime-Cam Subaru Strategic Program Field

“…Giles et al (2017) estimated that for their statistically complete sample of 34 X-ray galaxy clusters, the luminosity is ∼ 2.2 times higher for a given mass and a flatter relation is noted if selection effect is not taken into account in the 𝐿-𝑀 relation. Using a simplified approach, Molham et al (2020) also found their measured bias-uncorrected 𝐿-𝑇 relation of their X-ray-optical sample is biased to a steeper slope and higher normalization. As a result, not taking into account selection bias may have a noticeable impact on the measured scaling relations.…”

The eROSITA Final Equatorial-Depth Survey (eFEDS)

“…However, a plethora of studies report steeper L X − T (B ∼ 2.5) and L bol − T (B ∼ 3.0) relations compared to their selfsimilar predictions (e.g., Pratt et al 2009;Eckmiller et al 2011;Maughan et al 2012;Hilton et al 2012;Kettula et al 2015;Lovisari et al 2015;Zou et al 2016;Giles et al 2016;Molham et al 2020).…”