Abstract
Observations with the Imaging Proportional Counter reveal that three of the four galaxies in the Grus Quartet are X-ray emitters (NGC 7552, 7582, 7590). The strongest is the narrow emission line galaxy (NELG) NGC 7582, and we confirm, also using data from the Monitor Proportional Counter, that the variable 2A 2315--428 consists essentially of this galaxy only. In the spectrum of this galaxy evidence is found of a large photoelectric cutoff, with the corresponding N/sub H/ lying between 5 and 10 x 10/sup 22/ cm/sup -2/. It is shown that both the interstellar medium and the narrow emission line gas of this galaxy are unlikely to be the main causes of the cutoff. By analogy with NGC 4151, where the variable cutoff is attributed to the broad line emitting gas, N/sub H/ is found to be compatible with the upper limits that can be placed on the strength of broad line components in NGC 7582 and could therefore represent the first indirect evidence of very high velocity gas in the nuclei of NELGs. A crucial test to be pursued is time variability in the cutoff.
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