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Title: Radio Follow-Up of Gravitational-Wave Triggers during Advanced LIGO 01

Abstract

We present radio follow-up observations carried out with the Karl G. Jansky Very Large Array during the first observing run (O1) of the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO). A total of three gravitational-wave triggers were followed-up during the ≈4 months of O1, from 2015 September to 2016 January. Two of these triggers, GW150914 and GW151226, are binary black hole (BH) merger events of high significance. A third trigger, G194575, was subsequently declared as an event of no interest (i.e., a false alarm). Our observations targeted selected optical transients identified by the intermediate Palomar Transient Factory in the Advanced LIGO error regions of the three triggers, and a limited region of the gravitational-wave localization area of G194575 not accessible to optical telescopes due to Sun constraints, where a possible high-energy transient was identified. No plausible radio counterparts to GW150914 and GW151226 were found, in agreement with expectations for binary BH mergers. We show that combining optical and radio observations is key to identifying contaminating radio sources that may be found in the follow-up of gravitational-wave triggers, such as emission associated with star formation and active galactic nuclei. We discuss our results in the context of the theoretical predictions for radiomore » counterparts to gravitational-wave transients, and describe our future plans for the radio follow-up of Advanced LIGO (and Virgo) triggers.« less

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3];  [4]; ORCiD logo [5];  [6]; ORCiD logo [7]; ORCiD logo [8]; ORCiD logo [9]; ORCiD logo [2]
  1. Texas Tech Univ., Lubbock, TX (United States)
  2. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  3. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Univ. of Maryland, College Park, MD (United States)
  4. National Radio Astronomy Observatory, Socorro, NM (United States)
  5. Univ. of Copenhagen, Copenhagen (Denmark)
  6. Texas Tech Univ., Lubbock, TX (United States); Westview High School, Portland, OR (United States)
  7. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
  8. Weizmann Institute of Science, Rehovot (Israel)
  9. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21)
OSTI Identifier:
1393080
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal. Letters
Additional Journal Information:
Journal Volume: 829; Journal Issue: 2; Journal ID: ISSN 2041-8213
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; gravitational waves; radiation mechanisms: general; radio continuum: general

Citation Formats

Palliyaguru, N. T., Corsi, Alessandra, Kasliwal, M. M., Cenko, S. B., Frail, D. A., Perley, D. A., Mishra, N., Singer, L. P., Gal-Yam, A., Nugent, P. E., and Surace, J. A. Radio Follow-Up of Gravitational-Wave Triggers during Advanced LIGO 01. United States: N. p., 2016. Web. doi:10.3847/2041-8205/829/2/L28.
Palliyaguru, N. T., Corsi, Alessandra, Kasliwal, M. M., Cenko, S. B., Frail, D. A., Perley, D. A., Mishra, N., Singer, L. P., Gal-Yam, A., Nugent, P. E., & Surace, J. A. Radio Follow-Up of Gravitational-Wave Triggers during Advanced LIGO 01. United States. doi:10.3847/2041-8205/829/2/L28.
Palliyaguru, N. T., Corsi, Alessandra, Kasliwal, M. M., Cenko, S. B., Frail, D. A., Perley, D. A., Mishra, N., Singer, L. P., Gal-Yam, A., Nugent, P. E., and Surace, J. A. 2016. "Radio Follow-Up of Gravitational-Wave Triggers during Advanced LIGO 01". United States. doi:10.3847/2041-8205/829/2/L28. https://www.osti.gov/servlets/purl/1393080.
@article{osti_1393080,
title = {Radio Follow-Up of Gravitational-Wave Triggers during Advanced LIGO 01},
author = {Palliyaguru, N. T. and Corsi, Alessandra and Kasliwal, M. M. and Cenko, S. B. and Frail, D. A. and Perley, D. A. and Mishra, N. and Singer, L. P. and Gal-Yam, A. and Nugent, P. E. and Surace, J. A.},
abstractNote = {We present radio follow-up observations carried out with the Karl G. Jansky Very Large Array during the first observing run (O1) of the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO). A total of three gravitational-wave triggers were followed-up during the ≈4 months of O1, from 2015 September to 2016 January. Two of these triggers, GW150914 and GW151226, are binary black hole (BH) merger events of high significance. A third trigger, G194575, was subsequently declared as an event of no interest (i.e., a false alarm). Our observations targeted selected optical transients identified by the intermediate Palomar Transient Factory in the Advanced LIGO error regions of the three triggers, and a limited region of the gravitational-wave localization area of G194575 not accessible to optical telescopes due to Sun constraints, where a possible high-energy transient was identified. No plausible radio counterparts to GW150914 and GW151226 were found, in agreement with expectations for binary BH mergers. We show that combining optical and radio observations is key to identifying contaminating radio sources that may be found in the follow-up of gravitational-wave triggers, such as emission associated with star formation and active galactic nuclei. We discuss our results in the context of the theoretical predictions for radio counterparts to gravitational-wave transients, and describe our future plans for the radio follow-up of Advanced LIGO (and Virgo) triggers.},
doi = {10.3847/2041-8205/829/2/L28},
journal = {The Astrophysical Journal. Letters},
number = 2,
volume = 829,
place = {United States},
year = 2016,
month = 9
}

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  • We report the results of a deep search for an optical counterpart to the gravitational wave (GW) event GW150914, the first trigger from the Advanced LIGO GW detectors. We used the Dark Energy Camera (DECam) to image a 102 deg 2 area, corresponding to 38% of the initial trigger high-probability sky region and to 11% of the revised high-probability region. We observed in the i and z bands at 4–5, 7, and 24 days after the trigger. The median 5σ point-source limiting magnitudes of our search images are i = 22.5 and z = 21.8 mag. We processed the imagesmore » through a difference-imaging pipeline using templates from pre-existing Dark Energy Survey data and publicly available DECam data. Due to missing template observations and other losses, our effective search area subtends 40 deg 2, corresponding to a 12% total probability in the initial map and 3% in the final map. In this area, we search for objects that decline significantly between days 4–5 and day 7, and are undetectable by day 24, finding none to typical magnitude limits of i = 21.5, 21.1, 20.1 for object colors (i – z) = 1, 0, –1, respectively. Lastly, our search demonstrates the feasibility of a dedicated search program with DECam and bodes well for future research in this emerging field.« less
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