/////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19828 SUBJECT: INTEGRAL/SPI-ACS observation of IceCube HESE 128340 58537957 DATE: 16/08/21 12:04:41 GMT FROM: Volodymyr Savchenko at ISDC,U of Geneve V. Savchenko (APC, Paris, France) , C. Ferrigno (ISDC, University of Geneva, CH), P. Ubertini, A. Bazzano, L. Natalucci (INAF IAPS-Roma, Italy), S. Mereghetti (INAF IASF-Milano, Italy), P. Laurent (CEA, Saclay, France), E. Kuulkers (ESAC/ESA, Madrid, Spain) Using INTEGRAL/SPI-ACS we have performed a search for a prompt gamma-ray counterpart of the cosmic neutrino candidate IceCube HESE 128340 58537957. At the time of the event (2016-08-14 21:45:54 UTC, hereafter T0), INTEGRAL/SPI-ACS was operating in the nominal mode. The spacecraft was pointing in the direction of Norma Arm Region, and the neutrino localization was at an angle of 47.3 deg with respect to the pointing axis. This orientation enables high response of SPI-ACS. The background within +/-7000 seconds around the event was very stable, with only low-significance variations at 100 second time scale. We estimate a 3-sigma upper limit on the 75-2000 keV fluence of 3.1x10^-7 erg/cm^2 for a burst lasting less than 1 s with a characteristic short GRB spectrum (an exponentially cut off power law with alpha=-0.5 and Ep=500 keV) occurring at any time in the interval +/-1000 s around T0. For a typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and Ep=250 keV), the derived peak flux upper limit is ~1.9x10^-7 erg/cm^2/s at 1 s time scale in 75-2000 keV energy range. The SPI-ACS light curves, binned at 50 ms, are derived from 91 independent detectors with different lower energy thresholds (mainly between 50 keV and 150 keV) and an upper threshold at about 100 MeV. INTEGRAL has performed a pointed observation of the location of IceCube HESE 128340 58537957, starting 36 hours after the event. The results of this observation will be reported separately. /////////////////////////////////////////////////////////////////////// ATEL #9391 ATEL #9391 Title: INTEGRAL follow-up of IceCube HESE 128340 58537957 Author: V. Savchenko (APC, Paris, France) , C. Ferrigno (ISDC, University of Geneva, CH), P. Ubertini, A. Bazzano, L. Natalucci (INAF, IAPS-Roma, Italy), S. Mereghetti (INAF, IASF-Milano, Italy), P. Laurent (CEA, Saclay, France), E. Kuulkers (ESAC/ESA, Madrid, Spain) Queries: savchenk@apc.in2p3.fr Posted: 21 Aug 2016; 12:24 UT Subjects:X-ray, Neutrinos, Transient On 2016-08-14 21:45:54 the IceCube detector has observed a high-energy neutrino likely of astrophysical origin, HESE 128340 58537957. The location of the event is contained in a circle of 1.5 degree radius (systematic and statistical uncertainty, 90% confidence) centered at RA=199.3100 Dec=-32.0165, assuming that the interaction in the IceCube detector was track-like. INTEGRAL has performed an observation of the neutrino localization region, starting 36 hours after the neutrino detection from 2016-08-16 09:43:41 UTC to 2016-08-17 16:19:07 UTC, corresponding to a total on-target time of 100 ks. We have investigated the data collected by INTEGRAL IBIS and JEM-X without finding any significant new source in IBIS/ISGRI data between 20 and 200 keV within the localization area of HESE 128340 58537957. In the JEM-X 3-35 keV mosaic image corresponding to the whole observation period we identify an excess with SNR of 4.2. We have split the observation in two periods of equal duration, and verified that this excess is not detected with SNR more than 4 in any of them. The probability of this excess happening randomly in the region of interest is 25%. We derived an upper limit on the flux of any new source in the 90% localization region of the HESE 128340 58537953, averaged over the observation, of 6 mCrab (1.8x10-10 erg/cm2/s) in 3-35 keV, 3 mCrab (3.7x10-11 erg/cm2/s) in 20-60 keV , and 7 mCrab (8.2x10-11 erg/cm2/s) in 60-200 keV. We have also searched for new sources in the whole area covered by the observation with sensitivity no worse than 4 times the deepest target sensitivity: 16 degree diameter for JEM-X (3-35 keV) and 30 degrees for ISGRI (20-200 keV). We did not find any unidentified source with SNR larger than 5. INTEGRAL/SPI-ACS observation at the time of the neutrino detection is reported in GCN #19828. /////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19885 SUBJECT: Search for counterpart to IceCube-160814A with ANTARES DATE: 16/08/31 20:02:23 GMT FROM: Damien Dornic at CPPM,France D. Dornic (CPPM/CNRS), A. Coleiro (APC/Universite Paris Diderot), D. Turpin (CPPM/IRAP/CNRS) on behalf of the ANTARES Collaboration: Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported single high-energy (HESE) neutrino IceCube-160814A (AMON IceCube HESE 58537957 128340). The reconstructed origin was 25.9 degrees below the horizon for ANTARES, with this position remaining below the horizon from -3.3h, +13h around the time of the alert. Thus ANTARES had a high sensitivity to any neutrinos from the same region. ANTARES is the largest neutrino detector installed in the Mediterranean Sea, and is primarily sensitive to astrophysical neutrinos in the TeV-PeV energy range. At 10 TeV, the median angular resolution for muon neutrinos is below 0.5 degrees. In the range 1-100 TeV, ANTARES has the best sensitivity to this position in the sky. No up-going muon neutrino candidate events were recorded within three degrees of the IceCube event coordinates during a +/- 1h time-window centered on the IceCube event time. A search on an extended time window of +/- 1 day has also yielded no detection (68% visibility probability). This yields a preliminary 90% upper limit on the muon-neutrino fluence from a point source of 15.7 GeV.cm^-2 over the energy range 2.8 TeV-3.1PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and 43.0 GeV.cm^-2 (0.4-280 TeV) for an E^-2.5 spectrum.