Fossil group origins - VI. Global X-ray scaling relations of fossil galaxy clusters

Abstract

We present the first pointed X-ray observations of 10 candidate fossil galaxy groups and clusters. With these Suzaku observations, we determine global temperatures and bolometric X-ray luminosities of the intracluster medium (ICM) out to r<SUB>500</SUB> for six systems in our sample. The remaining four systems show signs of significant contamination from non-ICM sources. For the six objects with successfully determined r<SUB>500</SUB> properties, we measure global temperatures in the range 2.8 ≤ T<SUB>X</SUB> ≤ 5.3 keV, bolometric X-ray luminosities of 0.8 × 10<SUP>44</SUP> ≤ L<SUB>X, bol</SUB> ≤ 7.7 × 10<SUP>44</SUP> erg s<SUP>-1</SUP>, and estimate masses, as derived from T<SUB>X</SUB>, of M<SUB>500</SUB> ≳ 10<SUP>14</SUP> M<SUB>☉</SUB>. Fossil cluster scaling relations are constructed for a sample that combines our Suzaku observed fossils with fossils in the literature. Using measurements of global X-ray luminosity, temperature, optical luminosity, and velocity dispersion, scaling relations for the fossil sample are then compared with a control sample of non-fossil systems. We find the fits of our fossil cluster scaling relations are consistent with the relations for normal groups and clusters, indicating fossil clusters have global ICM X-ray properties similar to those of comparable mass non-fossil systems.