Searching the Gamma-ray Sky for Counterparts to Gravitational Wave   Sources: Fermi GBM and LAT Observations of LVT151012 and GW151226
  We present the Fermi Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) observations of the LIGO binary black hole merger event GW151226 and candi- date LVT151012. No candidate electromagnetic counterparts were detected by either the GBM or LAT. We present a detailed analysis of the GBM and LAT data over a range of timescales from seconds to years, using automated pipelines and new techniques for char- acterizing the upper limits across a large area of the sky. Due to the partial GBM and LAT coverage of the large LIGO localization regions at the trigger times for both events, dif- ferences in source distances and masses, as well as the uncertain degree to which emission from these sources could be beamed, these non-detections cannot be used to constrain the variety of theoretical models recently applied to explain the candidate GBM counterpart to GW150914. 
J. L. Racusin, E. Burns, A. Goldstein, V. Connaughton, C. A.   Wilson-Hodge, P. Jenke, L. Blackburn, M. S. Briggs, J. Broida...
astro-ph.HE