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Title: DESGW: Optical Follow-up of BBH LIGO-Virgo Events with DECam

Abstract

The DESGW program is a collaboration between members of the Dark Energy Survey, the wider astronomical community, and the LIGO-Virgo Collaboration to search for optical counterparts of gravitational wave events, such as those expected from binary neutron star mergers or neutron star-black hole mergers. While binary black hole (BBH) events are not expected to produce an electromagnetic (EM) signature, emission is certainly not impossible. The DESGW program has performed follow-up observations of four BBH events detected by LIGO in order to search for any possible EM counterpart. Failure to nd such counterparts is still relevant in that it produces limits on optical emission from such events. This is a review of follow-up results from O1 BBH events and a discussion of the status of ongoing uniform re-analysis of all BBH events that DESGW has followed up to date.

Authors:
 [1];  [2];  [3];  [3]
  1. Indiana U.
  2. Brandeis U.
  3. Fermilab
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1415630
Report Number(s):
FERMILAB-CONF-17-591-AE
1646014
DOE Contract Number:
AC02-07CH11359
Resource Type:
Conference
Resource Relation:
Conference: IAU Symposium 338, Baton Rouge, LA, USA, 10/16-10/19/2017
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Butler, Robert E., Soares-Santos, M., Annis, j., and Herner, K. DESGW: Optical Follow-up of BBH LIGO-Virgo Events with DECam. United States: N. p., 2017. Web.
Butler, Robert E., Soares-Santos, M., Annis, j., & Herner, K. DESGW: Optical Follow-up of BBH LIGO-Virgo Events with DECam. United States.
Butler, Robert E., Soares-Santos, M., Annis, j., and Herner, K. 2017. "DESGW: Optical Follow-up of BBH LIGO-Virgo Events with DECam". United States. doi:. https://www.osti.gov/servlets/purl/1415630.
@article{osti_1415630,
title = {DESGW: Optical Follow-up of BBH LIGO-Virgo Events with DECam},
author = {Butler, Robert E. and Soares-Santos, M. and Annis, j. and Herner, K.},
abstractNote = {The DESGW program is a collaboration between members of the Dark Energy Survey, the wider astronomical community, and the LIGO-Virgo Collaboration to search for optical counterparts of gravitational wave events, such as those expected from binary neutron star mergers or neutron star-black hole mergers. While binary black hole (BBH) events are not expected to produce an electromagnetic (EM) signature, emission is certainly not impossible. The DESGW program has performed follow-up observations of four BBH events detected by LIGO in order to search for any possible EM counterpart. Failure to nd such counterparts is still relevant in that it produces limits on optical emission from such events. This is a review of follow-up results from O1 BBH events and a discussion of the status of ongoing uniform re-analysis of all BBH events that DESGW has followed up to date.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Conference:
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  • We present two different search methods for electromagnetic counterparts to gravitational-wave (GW) events from ground-based detectors using archival NASA high-energy data from the Fermi Gamma-ray Burst Monitor (GBM) and RXTE All-sky Monitor (ASM) instruments. To demonstrate the methods, we use a limited number of representative GW background noise events produced by a search for binary neutron star coalescence over the last two months of the LIGO-Virgo S6/VSR3 joint science run. Time and sky location provided by the GW data trigger a targeted search in the high-energy photon data. We use two custom pipelines: one to search for prompt gamma-ray counterpartsmore » in GBM, and the other to search for a variety of X-ray afterglow model signals in ASM. We measure the efficiency of the joint pipelines to weak gamma-ray burst counterparts, and a family of model X-ray afterglows. By requiring a detectable signal in either electromagnetic instrument coincident with a GW event, we are able to reject a large majority of GW candidates. This reduces the signal-to-noise ratio of the loudest surviving GW background event by around 15–20%.« less
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