부산대학교 도서관

We have monitored Supernova 1987A in optical/near-infrared bands from a few weeks following its birth until the present time in order to search for a pulsar remnant. We have found an apparent pattern of emission near the frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14 ms period on numerous occasions over the next four years in data taken with a variety of telescopes, data systems and detectors, at a number of ground- and space-based observatories. The sequence of detections of this signal from Feb. `92 through August `93, prior to its apparent subsequent fading, is highly improbable (< 1.e-10) for any noise source). We also find evidence for modulation of the 2.14 ms period with a ~1,000 s period which, when taken with the high spindown of the source (2-3e-10 Hz/s), is consistent with precession and spindown via gravitational radiation of a neutron star with a non-axisymmetric oblateness of ~1e-6, and an implied gravitational luminosity exceeding that of the Crab Nebula pulsar by an order of magnitude.
Comment: LaTeX, 6 pages, 5 figures, to be published by PASP as the Proceedings of the SN1987A - Tens Years After conference