Backer et al.1,2 discovered PSR1937+214 at radiowavelengths. Djorgovski3 identified a candidate optical counterpart with a red-sensitive CCD on a 1-m telescope, although he found nothing on the paper prints of the Palomer Sky Survey. Manchester et al.4 at the Anglo-Australian Telescope reported optical pulses from a field including Djorgovski's red candidate, although they have not confirmedthis. Their 3.5 arcs field barely included the pulsar position. Two of us (M.J.L. and G.H.R.) have found a bright IR flux of 12.3 mag at 2.2 μm, an image at the plate limit on the red-sensitive glass print of the Sky Survey, and CO absorption bands, all for the red candidate5. We report here that it is probably an ordinary red giant. We do not find statistically significant pulsations at the pulsar frequency or any harmonic up to the fourth in 6 to 8 arc s fields including both the red candidate and the radio pulsar positions.
ASJC Scopus subject areas