OPTICAL APPEARANCE OF THE DEBRIS OF A STAR DISRUPTED BY A MASSIVE BLACK-HOLE

We show that the disruption of a star by a similar to 10(6) M. black h ole in a galactic nucleus could under favorable circumstances produce an optically thick envelope that radiates with a thermal spectrum at t he Eddington limit, similar to 10(44) ergs s(-1), for tens of years. T he low apparent temperature of this envelope, similar to 10(4) K, woul d be easily detectable in optical surveys. If most galaxies harbor a m assive black hole at their center, then the Sloan Digital Sky Survey m ight find hundreds of galaxies with nuclear activity of this type. Bec ause the envelope is driven to shine near the Eddington limit, a measu rement of the source redshift and total luminosity could yield the bla ck hole mass.