TITLE: GCN CIRCULAR NUMBER: 19363 SUBJECT: ICECUBE-160427A neutrino candidate event: updated direction information DATE: 16/04/29 16:29:47 GMT FROM: Erik Blaufuss at U. Maryland/IceCube IceCube detected a candidate cosmic neutrino IceCube-160427A, "AMON ICECUBE HESE 127853 67093193" at 05:52:32.00 UT on 16/04/27 (http://gcn.gsfc.nasa.gov/notices_amon/67093193_127853.amon) The event was a high energy starting event (HESE) with track-like characteristics and it arrived when the IceCube detector was in a normal operating state. ​ More sophisticated reconstruction algorithms have been applied offline, with the direction refined to RA=240.57d and DEC=+9.34d (J2000), and the position uncertainty reduced to an estimated 0.6 degrees or 36 arcminuntes radius (stat+sys, 90% containment). We encourage followup by ground and space-based instruments to help identify a possible astrophysical source for the neutrino. ​ The IceCube neutrino observatory is a cubic-kilometer neutrino detector operating at the geographic south Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu