New Transient Source, Cepheus X-4, Observed by OSO-7

A new, apparently transient, X-ray source, Cep X-4, was observed 1972 June 7 by the UCSD X-ray telescope on OSO-7. Subsequent observations by the lower-energy MIT X-ray telescope on the same satellite confirmed the source and provided an improved position of a = 211137n1, = 56?78 (1950 coordinates) with an error circle radius of 0?4. Best fits to the UCSD data in the 7-37 keV range were 6.5 x l0- E2(eE/I.'. ) -1 and 8 X 10- E2(eE/4. ) -1 photons (cm2 s keV) -1 on 1972 June and June 29-July 6, respectively. The source was undetected on two other occasions, with 2 upper limits being 10-2 photons (cm2 s) -1 for 1971 December 15-23 and 3 X 10-2 photons (cm2 s)-1 for 1973 February 15-16 in the more sensitive 7-26 keV energy range. Subject headings:spectra, X-ray-X-ray sources