A Search for Optical Pulsations from Two Young Southern Pulsars

Abstract

We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for PSR B1509-58, with a 2 sigma upper limit on the pulsed fraction of 12 percent, significantly lower than that measured in the five known optical pulsars. Given its low pulsed fraction, high optical luminosity, and significant (8 percent) chance coincidence probability, we suggest that this candidate is not associated with the pulsar. We also find that the still-unidentified optical counterpart of PSR B1706-44 has R>18 and lies within 3 arcsec of an R=16.6 star.

12 pages including 1 PS figure (revised). To appear in ApJ Letters