Three cosmic x-ray sources have been observed from a water-launched rocket carrying two x-ray detectors to an altitude of 200 kilometers. The x-ray spectra, measured in the photon energy range between I and 40 kiloelectron volts, are all different. The sources in order of hardness of spectra are Cyg XR-1, Tau XR-1, and Sco XR-1. The intensity of Sco XR-J decreased at low photon energies. The differences in spectra might source mechanisms.
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