SEARCH FOR CIRCUMSTELLAR MATERIAL AROUND NEARBY PULSARS THERMAL EMISSION OF DUSTY CLOUDS OR DISCS AROUND NEUTRON STARS

we propose to search for thermal dust emission from circumstellar discs, debris or clouds around nearby pulsars, that are the byproducts or progenitors of planet formation. it is suggested that planets can form or survive around old millisecond pulsars and intermediate age slow pulsars, although, so far, planets have only been detected orbiting millisecond pulsars. our main objective is to detect dust clouds or discs around neutron stars in which planets can form by a similar mechanism as in our solar system. in the case of the millisecond pulsar psr b1257+12, the disc most likely formed out of a companion star which either was dynamically disrupted or evaporated by the pulsar radiation. in the first case, the disc would surround a single, in the second, most likely case, a binary pulsar. discovery of a circumpulsar disc around a single or binary millisecond pulsar could therefore allow to distinguish between the two models, and discover intermediate stages of evolution between evaporating binary pulsars and isolated millisecond pulsars with planetary bodies in quasicircular orbits, such as psr b1257+12. in the case of ordinary radio pulsars, planetforming discs may also exist, if some material of the envelope of the progenitor was not ejected in the supernova in which the radio pulsar formed, but fell back to form a postsupernova disc. detection of such discs, ideally for pulsars of different ages, would have implications not only for the prospects of forming planets but also for our understanding of the basic supernova explosion mechanism. in these different pulsars we aim to deduce the radiating mass of dust and to compare its physical properties to that of the dusty discs around mainsequence and postmain sequence stars revealed by iras and groundbased infrared measurements. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]