Implications Of A Dark Sector U(1) For Gamma Ray Bursts
  We discuss the implications for gamma ray burst studies, of a dark unbroken $U(1)_D$ sector that couples predominantly through gravity to the visible sector. The dominant dark matter component remains neutral under $U(1)_D$. The collapsar model is assumed to explain the origin of long gamma ray bursts. The main idea is that by measuring the change in stellar black hole spin during the duration of the GRB, one can make inferences about the existence of a dark matter accretion disk. This could potentially provide evidence for the existence for a $U(1)_D$ sector. 
Tom Banks, Willy Fischler, Dustin Lorshbough, Walter Tangarife
astro-ph.HE gr-qc hep-ph hep-th