Compton scattering effects observed in Sco X-1 and similar sources.

Comptonized thermal bremsstrahlung spectra have been fitted to data from Sco X-1, 4U1702-36 (Sco X-2), 4U1813-14(GX17+2) and 4U1728-16(GX9+9). These spectral forms result in improved values of chi-square and give lower values of temperature when compared with pure bremsstrahlung spectra. We find an electron temperature for Sco X-1 of 2.4 keV (2.8 x 10 million K). There is no evidence for the correlation of temperature with intensity, which has been reported by previous authors. Instead, we observe that the optical depth and intensity of Sco X-1 are correlated.