K. De (Caltech), M. Hankins (Caltech), M. Coughlin (Caltech), M. M. Kasliwal (Caltech), S. M. Adams (Caltech), I. Andreoni (Caltech), S. Anand (Caltech), M. Sharma (Caltech), L. Singer (NASA GSFC), T. Ahumada (UMD), A. Moore (ANU), J. Soon (ANU), M. Ashley (UNSW), T. Travouillon (ANU), R. Soria (NAOC) report on behalf of the Palomar Gattini-IR team and the larger GROWTH (Global Relay of Observatories Watching Transients Happen) collaboration
We report wide-field near-infrared follow-up observations of the localization region of the gravitational wave event S200114f (GCN 26734) by the Palomar Gattini-IR survey (Moore and Kasliwal 2019). Gattini-IR is a newly commissioned near-IR camera with a field of view of 25 square degrees mounted on a robotic 30 cm telescope at Palomar observatory (De et al. 2020).
We started customized Target of Opportunity observations at UT 2020-01-14 05:02. The tiling was optimally determined and triggered using the GROWTH Target of Opportunity marshal (Coughlin et al. 2019a, Kasliwal et al. 2019b). We imaged a total of 479 square degrees, covering 89.1% of the probability region of the event until UT 11:21. We obtained a second epoch of observations starting the next night at at UT 2019-01-15 02:03 and continuing until UT 07:59. All data were processed and stacked with the Palomar Gattini-IR data reduction pipeline. The typical limiting magnitude of each field visit (300s second exposure time) was between 15.9 and 16.3 AB mag in J-band. No viable counterparts with at least two detections and without previous history of variability were identified in the single epoch stacks within the survey region.