{
  "bibcode": "2014GCN.15758....1S",
  "body": "L. P. Singer (Caltech), M. M. Kasliwal (Carnegie Observatories/Princeton),\nS. B. Cenko (NASA/GSFC), and Y. Cao (Caltech) report on behalf of the\nintermediate Palomar Transient Factory (iPTF) collaboration:\n\nWe have searched for optical counterparts of Fermi GBM trigger\n412093190 (2014-01-22 14:19:47.78) using the Palomar 48-inch Oschin\ntelescope (P48). Starting at 11.97 hours after the Fermi trigger, we\nimaged an area of 75 deg^2 within the GBM 1-sigma\nstatistical+systematic region, with a 34% chance of containing the\ntrue, unknown location of the source.\n\nWe sifted through 14,681 candidate variable sources using standard\niPTF vetting procedures. After obtaining spectra with the Palomar 200\ninch (P200) for the most promising sources, no compelling optical\nafterglow candidates survived. We note the following unrelated\noptical transients:\n\niPTF14ig, at R=19.9 +/- 0.1 mag, classified as a SN Ia based on P200\nobservations, at the coordinates:\n RA(J2000)  =  03h 32m 23.94s ( 53.099768 deg)\n Dec(J2000) = +10d 07' 06.2\"  (+10.118386 deg)\n\niPTF14ih, at R=20.2 +/- 0.2 mag, classified as a SN II based on P200\nobservations, on the outskirts of the galaxy 2MASX J03394459+1548035\na.k.a. PGC 1493639, at the coordinates:\n RA(J2000)  =  03h 39m 43.88s ( 54.932815 deg)\n Dec(J2000) = +15d 47' 43.4\"  (+15.795391 deg)\n\niPTF14ip, at R = 19.6 +/- 0.1 mag, on the edge of the galaxy SDSS\nJ034353.55+094512.9, at the coordinates:\n RA(J2000)  =  03h 43m 53.69s ( 55.973710 deg)\n Dec(J2000) = +09d 45' 13.1\"  (+09.753634 deg)\nGiven the nearby galaxy and lack of recent limits, we consider it\nlikely iPTF14ip is also an unrelated foreground supernova. We will\nattempt future observations to confirm its origin.\n\nA diagram of the locations of these candidates, the Fermi-GBM\nlocalization, and the ten P48 fields that we imaged can be found at\n<http://www.its.caltech.edu/~lsinger/iptf/Fermi412093190.pdf>.\n\nWe thank Andrew Drake for promptly obtaining the P200 spectra.",
  "circularId": 15758,
  "createdOn": 1390471484000,
  "email": "lsinger@caltech.edu",
  "subject": "Fermi412093190: iPTF optical counterpart search",
  "submitter": "Leo Singer at CIT/PTF  <lsinger@caltech.edu>"
}