Detection of X-ray Emission From Galaxies Inside The Bootes Void

Abstract

We report the x-ray properties of Bootes void galaxies detected by the ROSAT All-Sky Survey (RASS). By searching the fields of 26 radio and 27 emission-line-selected void galaxies, we have detected 9 x-ray emitting void galaxies at >2.7-sigma confidence level. Five of these 9 galaxies are in the IP,AS subsample. We expect 2 detections at the redshift of the Bootes void based on previous positional cross-correlation studies of the RASS and IRAS Point Source Catalogue sources. Three of the x-ray emitting galaxies are AGNs (IRAS~14288+5255, Mrk~845, and IRAS 15195+5050), and the remaining 6 are all likely emission line galaxies (PC~1357+4641, CG~547, CG~922, IRAS~14SOO+4804, CG~637, and IRAS~15092+3940). The far infrared flux levels of the AGN sources implies most of the observed x-ray emissivity is from starburst activity. We have carried out timing and spectral analysis for the narrow-line Seyfert 1 galaxy Mrk~845. Poor statistics prevents detailed analysis of the remaining sources. only two galaxies in our sample, BHI 1514+3819 and FSS 1515+3823, were observed during ROSAT pointed observations resulting in a nondetection at the 1-sigma level.