Evidence for emission in the MeV band from GRO J1837+59 and QSO 1739+522

O.R.Williams, K.Bennett, R.Much

V.Schonfelder, W.Collmar, H.Steinle

H.Bloemen, W.Hermsen



Emission in the MeV band from the region containing the bright unidentifed EGRET source GRO J1837+59 and the steep-spectrum EGRET blazar QSO 1739+522 was first reported by COMPTEL during an observation in November 1992. During this observation the emission was consistent with a single point source, designated GRO J1753+57. However, the location of GRO J1753+57 was not consistent with either GRO J1837+59 or QSO 1739+522 and identifying its counterpart in other wavelengths proved difficult. Moreover, subsequent observations suggested that the source could not in fact be described as a single point source and explanantions involving extended or multiple sources were invoked.

We present an analysis of recent obervations of this region, which confirm that the emission cannot arise from a single source, but can be modelled as a combination of emission from both GRO J1837+59 and QSO 1739+522. The spectrum and time variability derived for these two sources are discussed and compared to observations in neighbouring bands.

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On 16 Jul 1999, 09:19.