TY - JOUR

T1 - The XMM Cluster Survey

T2 - An independent demonstration of the fidelity of the eFEDS galaxy cluster data products and implications for future studies

AU - Turner, D J

AU - Giles, P A

AU - Romer, A K

AU - Wilkinson, R

AU - Upsdell, E W

AU - Klein, M

AU - Viana, P T P

AU - Hilton, M

AU - Bhargava, S

AU - Collins, C A

AU - Mann, R G

AU - Sahlén, M

AU - Stott, J P

PY - 2022/9/3

Y1 - 2022/9/3

N2 - Abstract We present the first comparison between properties of clusters of galaxies detected by the eROSITA Final Equatorial-Depth Survey (eFEDS) and the XMM Cluster Survey (XCS). We have compared, in an ensemble fashion, properties from the eFEDS X-ray cluster catalogue with those from the Ultimate XMM eXtragaLactic (XXL) survey project (XXL-100-GC). We find the redshift and temperature (TX) distributions to be similar, with a larger proportion of clusters above 4 keV in the XXL-100-GC sample; fractional temperature uncertainties are significantly larger in eFEDS compared to XXL. We find 62 eFEDS cluster candidates with XMM data (eFEDS-XMM sample); 10 do not have good enough XMM data to confirm or deny, 11 are classed as sample contaminants, and 4 have their X-ray flux contaminated by another source. The majority of eFEDS-XMM sources have longer XMM exposures than eFEDS, and most eFEDS positions are within 100 kpc of XCS positions. Our eFEDS-XCS sample of 37 clusters is used to calculate minimum sample contamination fractions of ∼18 per cent and ∼9 per cent in the eFEDS X-ray and optically confirmed samples respectively, in general agreement with eFEDS findings. We directly compare 29 X-ray luminosities (LX) measured by eFEDS and XCS, finding excellent agreement. Eight clusters have a TX measured by XCS and eFEDS, and we find that XMM temperatures are 25±9 per cent larger than their eROSITA counterparts. Finally, we construct LX - TX scaling relations based on eFEDS and XCS measurements, which are in tension; the tension is decreased when we measure a third scaling relation with calibrated XCS temperatures.

AB - Abstract We present the first comparison between properties of clusters of galaxies detected by the eROSITA Final Equatorial-Depth Survey (eFEDS) and the XMM Cluster Survey (XCS). We have compared, in an ensemble fashion, properties from the eFEDS X-ray cluster catalogue with those from the Ultimate XMM eXtragaLactic (XXL) survey project (XXL-100-GC). We find the redshift and temperature (TX) distributions to be similar, with a larger proportion of clusters above 4 keV in the XXL-100-GC sample; fractional temperature uncertainties are significantly larger in eFEDS compared to XXL. We find 62 eFEDS cluster candidates with XMM data (eFEDS-XMM sample); 10 do not have good enough XMM data to confirm or deny, 11 are classed as sample contaminants, and 4 have their X-ray flux contaminated by another source. The majority of eFEDS-XMM sources have longer XMM exposures than eFEDS, and most eFEDS positions are within 100 kpc of XCS positions. Our eFEDS-XCS sample of 37 clusters is used to calculate minimum sample contamination fractions of ∼18 per cent and ∼9 per cent in the eFEDS X-ray and optically confirmed samples respectively, in general agreement with eFEDS findings. We directly compare 29 X-ray luminosities (LX) measured by eFEDS and XCS, finding excellent agreement. Eight clusters have a TX measured by XCS and eFEDS, and we find that XMM temperatures are 25±9 per cent larger than their eROSITA counterparts. Finally, we construct LX - TX scaling relations based on eFEDS and XCS measurements, which are in tension; the tension is decreased when we measure a third scaling relation with calibrated XCS temperatures.

KW - Space and Planetary Science

KW - Astronomy and Astrophysics

U2 - 10.1093/mnras/stac2463

DO - 10.1093/mnras/stac2463

M3 - Journal article

VL - 517

SP - 657

EP - 674

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 1

ER -