GCN Circular 20491
Subject
SUBJECT: LIGO/Virgo G270580: Pan-STARRS and ATLAS observations of the skymap
Event
Date
2017-01-21T00:52:25Z (10 years ago)
From
S. J. Smartt at Queens U Belfast <s.smartt@qub.ac.uk>
L. Denneau, K. C. Chambers, J. Tonry, M. E. Huber (IfA), D. R. Young (QUB),
C. W. Stubbs (Harvard), S. J. Smartt, K. W. Smith (QUB),
M. Coughlin (Harvard), T.-W. Chen (MPE), H. Flewelling, A. Heinze,
E. A. Magnier (IfA), A. Rest (STScI), B. Stalder (IfA), A. S. B. Schultz,
C. Waters, R. J. Wainscoat, H. Weiland (IfA), D. E. Wright (QUB),
The optical wide-field imaging systems ATLAS (see Tonry et al. GCN 20377)
and Pan-STARRS1 (see Chambers et al. GCN 20383 ) were both
observing part of the northern arc of G270580 of the LALInference map
for Burst reconstruction (Veitch et al. PRD, 91, 04200, as released in GCN 20486).
These observations were taken during the night of 2017-01-20 UT, just a
few hours after the GW source was detected.
These were mostly normal survey operations, with some pointed PS1
footprints in z and y filters close to the end of the night in Hawaii.
Not enough dark hours were available to allow the sky map to be targeted
and mapped out in full.
These (mostly) serendipitous footprints for the night of 2017-01-20 UT
have been uploaded in two plots on GraceDB.
ATLAS covered 209 sq deg. (all post-detection of G270580) which corresponds
to a 10% likelihood of covering the position of the source. They were taken
1.5 - 3hrs after G270580 detection, reaching AB mag of o~19 (orange filter)
Pan-STARRS1 covered an area of 95 sq. deg. of the likelihood arc
(pointings which lie on non-zero probability regions) equating to 5%
probability of containing the source. These were take approximately
2-4hrs after G270580 detection, reaching AB mag of i,z ~ 20 and y~19.
Analysis is ongoing and any transients will be report.
Weather permitting, we will target much larger regions beginning on
the night of 2017-01-21 UT.