ROSATX‐Ray Observation of the Second Error Box for SGR 1900+14

The positions of the two error boxes for the soft gamma repeater (SGR) 1900+14 were determined by the "network synthesis" method, which employs observations by the Ulysses gamma-ray burst and CGRO BATSE instruments. The location of the first error box has been observed at optical, infrared, and X-ray wavelengths, resulting in the discovery of a ROSAT X-ray point source and a curious double infrared source. We have recently used the ROSAT HRI to observe the second error box to complete the counterpart search. A total of six X-ray sources were identified within the field of view. None of them falls within the network synthesis error box, and a 3 σ upper limit to any X-ray counterpart was estimated to be 6.35 × 10 -14 ergs cm -2 s -1 . The closest source is ~3' away, and has an estimated unabsorbed flux of 1.5 × 10 -12 ergs cm -2 s -1 . Unlike the first error box, there is no supernova remnant near the second error box. The closest one, G43.9+1.6, lies ~2 6 away. For these reasons, we believe that the first error box is more likely to be the correct one.