HEXTE Detections of Hard X-Ray Tails in Sco X-1

摘要: We report the detection of a non-thermal hard X-ray component from Sco X-1 based upon analysis 20-220 keV spectra obtained with HEXTE experiment on-board RXTE satellite. find that addition power-law to thermal bremsstrahlung model is required achieve good fit in 5 16 observations analyzed. Using PCA data we were able track movement source along Z diagram, and found presence tail not confined specific position. However, do observe an indication power law index hardens increasing mass accretion rate, as indicated position on diagram. derived luminosities are at order 10% for brightest atoll sources.