The Host Galaxy of the Quasar HE 0450−2958

A recent study suggests that the quasar HE 0450-2958 is hosted by a galaxysubstantially fainter than that inferred from the correlation between blackhole mass and bulge luminosity. As this result has significant bearings ongalaxy and black hole evolution, we revisit the issue by performing anindependent analysis of the data, using a two-dimensional image fittingtechnique. We indeed find no evidence of a host galaxy either, but, due to thebrightness of the quasar and uncertainties in the point-spread function, thelimits are fairly weak. To derive an upper limit on the host galaxy luminosity,we perform simulations to deblend the quasar from the host under conditionssimilar to those actually observed. We find that the host galaxy has anabsolute magnitude upper limit of -20 < M_V < -21, in good agreement with theprevious determination. Since this limit is consistent with the value predictedfrom the current best estimate of the black hole mass, there is no compellingevidence that the quasar HE 0450-2958 has an abnormally underluminous hostgalaxy. We also show that, contrary to previous claims, the companion galaxy toHE 0450-2958 should not be be regarded as an ultraluminous infrared galaxy.Comment: To appear in ApJ; 7 pages, 4 figures, uses emulateapj5.st