title: Limits on the cosmological abundance of supermassive compact objects from a millilensing search in gamma-ray burst data.
abstract: A new search for the gravitational lens effects of a significant cosmological density of supermassive compact objects (SCOs) on gamma-ray bursts (GRBs) has yielded a null result. We inspected the timing data of 774 BATSE-triggered GRBs for evidence of millilensing: repeated peaks similar in light-curve shape and spectra. Our null detection leads us to conclude that, in all candidate universes simulated, Omega(SCO)<0.1 is favored for SCO masses in the range 10(5)<M(SCO)/M( middle dot in circle)<10(9), while in some universes and mass ranges the density limits are as much as 10 times lower. Therefore, a cosmologically significant population of SCOs near globular cluster mass did not come out of the primordial universe or condense at recombination.
authors.affiliation: Michigan Technological University, Department of Physics, 1400 Townsend Drive, Houghton, Michigan 49931, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Nemiroff
authors.forename: G F
authors.initials: GF
authors.lastname: Marani
authors.forename: J P
authors.initials: JP
authors.lastname: Norris
authors.forename: J T
authors.initials: JT
authors.lastname: Bonnell