• DOI:10.3847/2041-8205/826/1/L6
• Corpus ID: 41946613

Fermi GBM Observations of LIGO Gravitational Wave event GW150914

@article{Connaughton2016FermiGO,
  title={Fermi GBM Observations of LIGO Gravitational Wave event GW150914},
  author={Valerie Connaughton and Eric Burns and Adam Goldstein and Lindy Blackburn and M S Briggs and B.-B. Zhang and Jordan B. Camp and Nelson Christensen and C. M. Hui and Peter Jenke and Tyson B. Littenberg and J. Mcenery and Judith L. Racusin and Peter Shawhan and Leo P. Singer and John Veitch and Colleen A. Wilson-Hodge and P. N. Bhat and Elisabetta Bissaldi and William H. Cleveland and Gerard Fitzpatrick and Misty M. Giles and Melissa Gibby and A. von Kienlin and R. Marc Kippen and Sheila McBreen and Bagrat G. Mailyan and Charles A. Meegan and W. S. Paciesas and R. D. Preece and Oliver J. Roberts and Linda S. Sparke and Matthew Stanbro and K. Toelge and P{\'e}ter Veres},
  journal={The Astrophysical Journal},
  year={2016},
  volume={826}
}

• V. Connaughton, E. Burns, +32 authors P. Veres
• Published 11 February 2016
• Physics
• The Astrophysical Journal

With an instantaneous view of 70% of the sky, the Fermi Gamma-ray Burst Monitor (GBM) is an excellent partner in the search for electromagnetic counterparts to gravitational-wave (GW) events. GBM observations at the time of the Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914 reveal the presence of a weak transient above 50 keV, 0.4 s after the GW event, with a false-alarm probability of 0.0022 (2.9(sigma)). This weak transient lasting 1 s was not detected by any other instrument and does not appear to be connected with other previously known astrophysical, solar, terrestrial, or magnetospheric activity. Its localization is ill-constrained but consistent with the direction of GW150914. The duration and spectrum of the transient event are consistent with a weak short gamma-ray burst (GRB) arriving at a large angle to the direction in which Fermi was pointing where the GBM detector response is not optimal. If the GBM transient is associated with GW150914, then this electromagnetic signal from a stellar mass black hole binary merger is unexpected. We calculate a luminosity in hard X-ray emission between 1 keV and 10 MeV of 1.8(sup +1.5, sub -1.0) x 10(exp 49) erg/s. Future joint observations of GW events by LIGO/Virgo and Fermi GBM could reveal whether the weak transient reported here is a plausible counterpart to GW150914 or a chance coincidence, and will further probe the connection between compact binary mergers and short GRBs.