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Neighbours, J. E.

Publications and source records attributed to Neighbours, J. E..

Observations of a bright, variable X-ray source in a globular cluster

The source 3U 1820-30 in NGC 6624 has been observed with the OSO-7 satellite. It shows variability of up to a factor of 5 in intensity over days and months and of a factor of 2 in about 5-10 minutes, but there are no evident periodicities. The luminosity of the source is 10 to the 38th ergs per sec (1-10 keV). Arguments are examined which suggest that mass accretion onto a neutron star or black hole provides the most likely mechanism of X-ray production.

Canizares, C. R.↗

A search for X-rays from supernova 1972e with Uhuru and OSO-7

The results of observations performed with X-ray detectors aboard OSO-7 and Uhuru at 13 different times ranging from 16 months before to 2 years after Sn 1972e maximum light are reported. Only one possible (3.2 sigma) positive result was found. The absence of any sizable flux contradicts the model of Shklovsky and imposes limitations on the model of Colgate and McKee.

Canizares, C. R.↗

A survey of trapped low energy electrons near the inner boundary of the inner radiation zone from the OSO-7

Data from the MIT X-ray experiment on the OSO-7 satellite were used to delineate the regions in B-L and geographic spaces where trapped radiation was encountered. The results pertain specifically to electrons with energies in a range of 10 keV centered on 55 keV which were encountered in an orbit between altitudes of 330 and 570 km and latitudes of 33.3 degrees. A typical pitch angle distribution is fitted by a Gaussian with a FWHM of 28 degrees.

Neighbours, J. E.↗