Deep optical observations at the position of PSR1706-44 with the VLT-UT1

We present optical data gathered by the VLT Test Camera in the V-band at th e radio (interferometric) position of PSR1706-44. We find no optical counte rpart to the pulsar in the VLT image. At a distance of 2." 7 from a nearby bright star, the 3 sigma upper limit to the pulsar magnitude above the back ground is V = 25.5. Within an error circle of 1." 0 the upper limit is degr aded in the direction towards the star. At a distance less than or similar to 2 " from the star we can with confidence only claim an upper limit of V = 24.5. This is still several magnitudes fainter than previous estimates. T he implications of the optical upper limit taken together with the high ene rgy pulsed gamma-ray radiation for theoretical models of pulsar emission ar e discussed.