2005/11/11 by Bregman, Joel N.
#Astrophysics (astro-ph) #FOS: Physical sciences
paper · doi:10.48550/arxiv.astro-ph/0511368
An analysis of the radio and X-ray luminosities, along with black hole masses has led to a relationship, the fundamental plane of black hole activity, where logLR = 0.60logLX + 0.78logMBH. We show that this same relationship can be obtained by using upper limit data or by randomizing the radio fluxes. In those cases, the relationship arises because one is effectively plotting distance vs distance in a flux-limited sample of objects. To correctly establish a relationship between LR, LX, and MBH, one would need to analyze a volume-limited sample of objects. The distance effect can be removed from the sample, where a relationship between LR/LX and MBH is found, showing that the LR rises more quickly than LX with increasing MBH. However, until a well-define sample is used, it is unclear the degree to which this relationship is influenced by the sample-selection.