1997A&A...323..839N

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.