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Multiwavelength observations of 26W20, a radio galaxy which displays BL Lac characteristics

J. D. Silverman·D. E. Harris·W. Junor
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Abstract

26W20, a radio galaxy located at a projected distance of 2.2 Mpc from the center of Abell 754 (z=0.054) exhibits core emission properties similar to those of a BL Lac object. New radio observations and VLA archival data show parsec scale features in the core (L_{r} approx.10^{41}) ergs/s with a flat spectrum. From observations with ROSAT, we demonstrate that the X-ray core emission (L_{x}=3X10^{43}) ergs/s is non-thermal and variable. An 18% increase in the X-ray luminosity was observed in two observations separated by five days. The optical morphology is that of a large, normal elliptical galaxy (m_{v}=15.6) and the optical spectrum lacks strong emission lines. If the innermost segment of the radio jet is close to our line of sight, Doppler boosting could explain both the observed X-ray intensity and the absence of emitting line regions.

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J. D. Silverman, D. E. Harris, W. Junor. 1998-04-20. Multiwavelength observations of 26W20, a radio galaxy which displays BL Lac characteristics. https://arxiv.org/abs/astro-ph/9804197

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