Young Circumstellar Disks near Evolved Massive Stars and Supernovae

There is increasing evidence that low mass stars with circumstellar disks canbe born close to massive stars, in some cases within tenths of a pc. If thedisks have lifetimes greater than those of the more massive stars, they areexposed to the radiation fields and gas flows from the late evolutionary phasesand supernovae of the massive stars. The fast flows from supernovae are likelyto give some stripping of mass from the disks, but do not typically lead tocomplete disruption of the disks. In the slow wind from a red supergiant star,there is the possibility of gravitational accretion of wind matter onto thecircumstellar disk. In the supernova explosion of a red supergiant, theradiative flux at the time of shock breakout can heat and ionize a nearby disk,leading to transient, narrow line emission. There are consequences for thesolar nebula if it was born ~0.2 pc from a massive star that became a redsupergiant. Accretion from the wind could supply a substantial amount of 26Alto the disk. The high radiative luminosity of the eventual supernova could leadto the melting of dust grains and the formation of chondrules. The passage ofthe supernova ejecta could drive a shock wave in the disk, heating it.Comment: 9 pages, ApJL, submitte