No CrossRef data available.
Published online by Cambridge University Press: 12 April 2016
During a pointed ROSAT observation in the direction of the Coma cluster of galaxies an exceptionally bright EUV source, RE J1255+266, was detected serendipitously. The source is located close to the Galactic North pole, at bII ~ 89°. Its observed EUV flux (62-110 eV) at the time of the detection was of order 7 × 10−9 ergs s−1 cm−2, making RE J1255+266 temporarily one of the brightest EUV sources on the sky.
The EUV flare of RE J1255+266 has a light curve with a decay time of about 0.86 days. With respect to earlier non-detections, the source brightened by a factor of > 7000. Such a behavior has not been observed before. Thus, it is unclear what type of source RE J1255+266 might be. The most likely optical counterpart is a faint (V ~ 18.5 mag) object with a blue spectrum (taken from an objective-prism Schmidt plate). For more details on the optical identification see the paper by J. Pye (this conference).
Simultaneous observations with CGRO/BATSE resulted in non-detections of the source in the 8-50 keV energy range.