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Title: ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914

Abstract

In view of the recent report by Connaughton et al., we analyze continuous time-tagged event (TTE) data of Fermi -gamma-ray burst monitor (GBM) around the time of the gravitational-wave event GW 150914. We find that after proper accounting for low-count statistics, the GBM transient event at 0.4 s after GW 150914 is likely not due to an astrophysical source, but consistent with a background fluctuation, removing the tension between the INTEGRAL /ACS non-detection and GBM. Additionally, reanalysis of other short GRBs shows that without proper statistical modeling the fluence of faint events is over-predicted, as verified for some joint GBM–ACS detections of short GRBs. We detail the statistical procedure to correct these biases. As a result, faint short GRBs, verified by ACS detections, with significances in the broadband light curve even smaller than that of the GBM–GW150914 event are recovered as proper non-zero source, while the GBM–GW150914 event is consistent with zero fluence.

Authors:
;  [1];  [2];  [3]
  1. Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching (Germany)
  2. Oskar Klein Centre for Cosmoparticle Physics, SE-106 91 Stockholm (Sweden)
  3. Francois Arago Centre, APC, Université Paris Diderot, CNRS/IN2P3, CEA/Irfu, Observatoire Paris, Sorbonne Paris Cité, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13 (France)
Publication Date:
OSTI Identifier:
22654195
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 827; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCOUNTING; ASTROPHYSICS; COSMIC GAMMA BURSTS; DETECTION; DIAGRAMS; FLUCTUATIONS; GAMMA RADIATION; GRAVITATIONAL WAVES; SIMULATION; VISIBLE RADIATION

Citation Formats

Greiner, J., Yu, H.-F., Burgess, J. M., and Savchenko, V., E-mail: jcg@mpe.mpg.de, E-mail: sptfung@mpe.mpg.de, E-mail: jamesb@kth.se, E-mail: savchenk@apc.in2p3.fr. ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914. United States: N. p., 2016. Web. doi:10.3847/2041-8205/827/2/L38.
Greiner, J., Yu, H.-F., Burgess, J. M., & Savchenko, V., E-mail: jcg@mpe.mpg.de, E-mail: sptfung@mpe.mpg.de, E-mail: jamesb@kth.se, E-mail: savchenk@apc.in2p3.fr. ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914. United States. doi:10.3847/2041-8205/827/2/L38.
Greiner, J., Yu, H.-F., Burgess, J. M., and Savchenko, V., E-mail: jcg@mpe.mpg.de, E-mail: sptfung@mpe.mpg.de, E-mail: jamesb@kth.se, E-mail: savchenk@apc.in2p3.fr. 2016. "ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914". United States. doi:10.3847/2041-8205/827/2/L38.
@article{osti_22654195,
title = {ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914},
author = {Greiner, J. and Yu, H.-F. and Burgess, J. M. and Savchenko, V., E-mail: jcg@mpe.mpg.de, E-mail: sptfung@mpe.mpg.de, E-mail: jamesb@kth.se, E-mail: savchenk@apc.in2p3.fr},
abstractNote = {In view of the recent report by Connaughton et al., we analyze continuous time-tagged event (TTE) data of Fermi -gamma-ray burst monitor (GBM) around the time of the gravitational-wave event GW 150914. We find that after proper accounting for low-count statistics, the GBM transient event at 0.4 s after GW 150914 is likely not due to an astrophysical source, but consistent with a background fluctuation, removing the tension between the INTEGRAL /ACS non-detection and GBM. Additionally, reanalysis of other short GRBs shows that without proper statistical modeling the fluence of faint events is over-predicted, as verified for some joint GBM–ACS detections of short GRBs. We detail the statistical procedure to correct these biases. As a result, faint short GRBs, verified by ACS detections, with significances in the broadband light curve even smaller than that of the GBM–GW150914 event are recovered as proper non-zero source, while the GBM–GW150914 event is consistent with zero fluence.},
doi = {10.3847/2041-8205/827/2/L38},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 827,
place = {United States},
year = 2016,
month = 8
}
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