Photometry and proper motion of the Vela pulsar *
F.P. Nasuti 1,
R. Mignani 1,
P.A. Caraveo 1 and
G.F. Bignami 1, 2
Received 27 June 1996 / Accepted 29 August 1996
We present the first UBVR photometry of the Vela Pulsar. All observed colours lie significantly above any Rayleigh-Jeans extrapolation of the ROSAT soft X-ray black body curve. While the U, B and V fluxes can be described by a flat power law, the R point lies about 1 magnitude below the expectation. An evidence for a similar spectral turnover, but at longer wavelength, was also claimed for the Crab Pulsar, another young INS with non-thermal optical emission. However, to account for the Vela R point in term of synchrotron self absorption, the emission geometry of the two pulsars must be different.
In parallel, we have used the new images to re-assess the proper motion of the Vela pulsar, an effect for which vastly different results have been reported in the literature.
Key words: pulsars: Vela pulsar astrometry
Send offprint requests to: P. Caraveo
© European Southern Observatory (ESO) 1997
Online publication: May 26, 1998