Discovery of 16.6 and 25.5 Second Pulsations from the Small Magellanic Cloud

Abstract

We report the serendipitous detection of two previously unreported pulsars from the direction of the Small Magellanic Cloud, with periods of 16.6 and 25.5 s. The detections are based on archival Proportional Counter Array data from the Rossi X-Ray Timing Explorer . The observation leading to these detections occurred in 2000 September, extending over 2.1 days with an exposure of 121 ks. A possible identification of the 16.6 s pulsar with an X-ray source (RX J0051.8-7310) seen by both the ROSAT and ASCA imaging X-ray satellites is presented.