Search for Periodicities Near 59 S in the Cos-B Gamma-Ray Data of 2CG 195+04 (geminga)
Caraveo, P. A.; Bignami, G. F.; Hermsen, W.; Pollock, A. M. T.; Bennett, K.; Buccheri, R.; Mayer-Hasselwander, H. A.; Sacco, B.
Italy, France, Netherlands, Germany
Abstract
The COS-B data relating to five observations in the general direction of Geminga, spanning 6.7 years, were searched for pulsation near 59 s. The SAS-2 indication is not confirmed. An indication of a 59 s pulsation in the gamma ray emission from 2CG195+04 (Geminga) was reported. Early analysis of COS-B data supported the result while later improved statistics did not confirm it. Subsequently, detection of a 59 s pulsation in the emission from the direction of Geminga at ultra high gamma and X-rays was reported. Geminga was identified with the X-ray source 1E0630+128. The final COS-B data on Geminga which was observed five times for a total of 214 days are reported.