Is the GW150914-GBM really associated with the GW150914?

Abstract

Finding the electromagnetic (EM) counterpart is critically important for a gravitational wave event. Although many efforts have been made to search for the purported EM counterpart of GW150914, the first gravitational wave event detected by LIGO, only Fermi/GBM reported an excess above background (i.e. GW150914-GBM) at 0.4 s after the LIGO trigger time, that is possibly associated with this GW event (Connaughton et al. 2016). However, since there is no significant detection by the INTEGRAL/SPI-ACS around the time of GW150914-GBM, a great debate has been raised about whether GW150914-GBM is of astrophysical origin and associated with the GW150914 (Savchenko et al. 2016). In order to answer this question, we re-analyzed the GBM data with a straightforward but sophisticated method. We find that the excess of GW150914-GBM mostly comes from those detectors with bad viewing angles to the GW event, whereas the good viewing detectors see nothing significant beyond background fluctuation around the trigger time of GW150914. This finding suggests that GW150914-GBM is very unlikely associated with the GW150914. Given that GW150914-GBM is the only event found by GBM that is possibly associated with this GW event in a comprehensive search, we conclude that GBM did not detect any electromagnetic radiation from the GW150914.

4 pages, 2 figures, comments are very welcome

References in corpus (4)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• Fermi GBM Observations of LIGO Gravitational Wave event GW150914
• Localization and broadband follow-up of the gravitational-wave transient GW150914
• INTEGRAL upper limits on gamma-ray emission associated with the gravitational wave event GW150914

Cited by in corpus (9)

• Theoretical Physics Implications of the Binary Black-Hole Mergers GW150914 and GW151226
• Electromagnetic signals following stellar-mass black hole mergers
• Disks Around Merging Binary Black Holes: From GW150914 to Supermassive Black Holes
• Probing extra dimension through gravitational wave observations of compact binaries and their electromagnetic counterparts
• Evolution of an Accretion Disk in Binary Black Hole Systems
• Mergers of accreting stellar-mass black holes
• Possible associated signal with GW150914 in the LIGO data
• Test of the Weak Equivalence Principle using LIGO observations of GW150914 and Fermi observations of GBM transient 150914
• Strategies for the Follow-up of Gravitational Wave Transients with the Cherenkov Telescope Array