GW150914: First search for the electromagnetic counterpart of a gravitational-wave event by the TOROS collaboration

Abstract

We present the results of the optical follow-up conducted by the TOROS collaboration of the first gravitational-wave event GW150914. We conducted unfiltered CCD observations (0.35-1 micron) with the 1.5-m telescope at Bosque Alegre starting ~2.5 days after the alarm. Given our limited field of view (~100 square arcmin), we targeted 14 nearby galaxies that were observable from the site and were located within the area of higher localization probability. We analyzed the observations using two independent implementations of difference-imaging algorithms, followed by a Random-Forest-based algorithm to discriminate between real and bogus transients. We did not find any bona fide transient event in the surveyed area down to a 5-sigma limiting magnitude of r=21.7 mag (AB). Our result is consistent with the LIGO detection of a binary black hole merger, for which no electromagnetic counterparts are expected, and with the expected rates of other astrophysical transients.

ApJ Letters, in press

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Cited by in corpus (8)

• Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration
• Variability Properties of 4 Million Sources in the $TESS$ Input Catalog Observed with the Kilodegree Extremely Little Telescope Survey
• A search for low-energy neutrinos correlated with gravitational wave events GW150914, GW151226 and GW170104 with the Borexino detector
• Evolution of dwarf galaxies hosting GW150914-like events
• Detecting optical transients using artificial neural networks and reference images from different surveys
• On similarity of binary black hole gravitational-wave skymaps: to observe or to wait?
• Limits on the Electro-Magnetic Counterpart of Binary Black Hole Coalescence at Visible Wavelengths
• Finding Fast Transients in Real Time Using Novel Light Curve Analysis Algorithm