//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20247 SUBJECT: IceCube-161210: IceCube observation of a high-energy neutrino candidate event DATE: 16/12/11 03:52:55 GMT FROM: Erik Blaufuss at U. Maryland/IceCube Erik Blaufuss(University of Maryland) reports on behalf of the IceCube Collaboration (http://icecube.wisc.edu/). On 2016/12/10 IceCube detected a track-like, very-high-energy event with a high probability of being of astrophysical origin. The event was a Extremely High Energy (EHE) event. The IceCube detector was in a normal operating state. EHE events have a neutrino interaction vertex outside the detector, produce a muon that traverses the detector volume and have a high light level (a proxy for energy). After the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon/80127519_128906.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2016/12/10 Time: 16 20:07:16 UT RA: 46.58 deg (+1.10 -1.00deg 90% PSF containment) J2000 Dec: 14.98 deg (+0.45 -0.40 deg 90% PSF containment) J2000 Additionally, we confirm the astrophysical signal probability reported initially. This event was found at the threshold for alert generation, with roughly equal chances of being of astrophysical origin or arising from an atmospheric (background) neutrino interaction. We encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate 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 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20248 SUBJECT: IceCube-161210: MAXI/GSC non-detection DATE: 16/12/11 15:18:54 GMT FROM: H. Negoro at Nihon U. H. Negoro, K. Tanaka (Nihon U.), T. Sakamoto (AGU), S. Ueno, H. Tomida, S. Nakahira, M. Ishikawa, Y. Sugawara (JAXA), T. Mihara, M. Sugizaki, M. Serino, W. Iwakiri, M. Shidatsu, J. Sugimoto, T. Takagi, M. Matsuoka (RIKEN), N. Kawai, N.Isobe, S.Sugita, T. Yoshii, Y. Tachibana, Y. Ono, T. Fujiwara, S. Harita, Y. Muraki (Tokyo Tech), A. Yoshida, Y. Kawakubo, Y. Kitaoka (AGU), H. Tsunemi, R. Shomura (Osaka U.), M. Nakajima, T. Masumitsu, T. Kawase (Nihon U.), Y. Ueda, T. Kawamuro, T. Hori, A. Tanimoto, S. Oda (Kyoto U.), Y. Tsuboi, Y. Nakamura, R. Sasaki (Chuo U.), M. Yamauchi, K. Furuya, C. Hanyu (Miyazaki U.), K. Yamaoka (Nagoya U.), Y. E. Nakagawa (JAMSTEC) report on behalf of the MAXI team: We report the non-detection of the IceCube-161210 event (Blaufuss GCN 20247) by MAXI/GSC. The event region was observed with MAXI/GSC at T0+12 min (T0 = 2016/12/10 20:07:16), and no significant enhancement was detected. A typical 3 sigma upper limit in the 4-10 keV band in a single scan transit is 20 mCrab. We note that the GCN/MAXI NOTICE (EVENT_ID_NUM 732899998) at 02:27 on 11 December 2016 was unintentionally distributed, triggered by an email to the MAXI mailing list to inform this non-detection. We aplogize for the confusion. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20249 SUBJECT: INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161210 DATE: 16/12/11 15:50:29 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 and IBIS/Veto we have performed a search for a prompt gamma-ray counterpart of the cosmic neutrino candidate IceCube-161210 (GCN 20247). At the time of the event (2016-12-10 20:07:16 UTC, hereafter T0), INTEGRAL was operating in nominal mode. The neutrino localization was at an angle of 136 deg with respect to the spacecraft pointing axis. This orientation implies moderately suppressed response of SPI-ACS, the response of IBIS/Veto was close to optimal. The best sensitivity to bursts longer than 8 s was achieved by IBIS/Veto, to those shorter - by SPI-ACS. The background within ±300 seconds around the event was very stable. However, 139 seconds after T0 INTEGRAL/SPI-ACS detected a short excess in a single bin (50 ms), consistent with the properties of the excesses produced in SPI-ACS by cosmic ray interactions. We do not detect any significant counterparts and estimate a 3-sigma upper limit on the 75-2000 keV fluence of 4.6x10^-7erg/cm^2for 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 ±300 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 ~4.5x10^-7(6.2x10^-7) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range. No pointed INTEGRAL observations of the location of IceCube-161103 have been performed or planned due to visibility constraints. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20250 SUBJECT: HAWC follow-up on IceCube-161210 DATE: 16/12/13 18:15:22 GMT FROM: Israel Martinez at HAWC Israel Martinez (University of Maryland) reports on behalf of the HAWC collaboration (http://www.hawc-observatory.org/collaboration/): On 2016/12/10 20:07:16 UT IceCube detected a track-like, very-high-energy event with a high probability of being of astrophysical origin, at RA=46.58d and Dec=14.98d J2000. It was reported in GCN circular 20247. Two analyses were performed: * Search for a steady source. This analysis was performed on archival data from November 2014 to June 2016. Assuming a spectral index of -2.3 we searched in a rectangular window corresponding to IceCube's 90% PSF containment for the event (1.72deg^2). The maximum significance is 2.83 sigma at RA=47.46d and Dec=14.59d. We estimate the number of trials to be ~70. We set an upper limit 95% CL on gamma rays for this period of: E^2 dN/dE = 3.23e-13 (E/TeV)^-0.3 TeV cm^-2 s^-1. * Search for a transient source. The event location was not in HAWC's FOV at the time of detection, so this analysis was performed using data corresponding to the two nearest 6hrs transits (MJD 57732.05-57732.30 and 57733.05-57733.30). Using the same spectral index and search window, the maximum significance is 1.71 sigma at RA=46.57d and Dec=15.18d. We set an upper limit 95% CL on gamma rays for this period of: E^2 dN/dE = 1.54e-11 (E/TeV)^-0.3 TeV cm^-2 s^-1. HAWC is a very-high-energy gamma-ray observatory located in Central Mexico at latitude 19 deg North. It operates day and night with over 95% duty cycle, HAWC has an instantaneous field of view of 2 sr and surveys 2/3 of the sky every day. It is sensitive to gamma rays from 300 GeV to 100 TeV. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20253 SUBJECT: IceCube-161210: CALET Gamma-Ray Burst Monitor upper limits DATE: 16/12/14 12:04:41 GMT FROM: Takanori Sakamoto at AGU Y. Kawakubo, A. Yoshida, T. Sakamoto, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration: We have performed a search for an X-ray and a gamma-ray counterpart using the CALET Gamma-ray Burst Monitor (CGBM) data around the on-set of the very-high-energy neutrino candidate IceCube-161210 (Blaufuss, GCN Circ. 20247). The position of the IceCube event at the event time was inside the field of view of HXM (the incident angle was 48 deg) and SGM (the incident angle was 51 deg). No CGBM on-board trigger happened around the IceCube event time. By using the CGBM time-history data (0.125 s time resolution), we found no significant signal between +-30 s from the IceCube event time. We estimate 7-sigma upper limit of SGM in the 50-1000 keV band as 5.6 x 10^-7 erg cm^-2 s^-1 assuming a single power-law model with a photon index of -2 in 1 s exposure. All the quoted values are preliminary and subject to change by a further analysis. The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20256 SUBJECT: IceCube-161210: Konus-Wind upper limits DATE: 16/12/14 15:23:56 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report: Using Konus-Wind (KW) data, we have performed a search for a gamma-ray transient around the time of the cosmic neutrino candidate IceCube-161210 (Blaufuss, GCN 20247; https://gcn.gsfc.nasa.gov/notices_amon/80127519_128906.amon) No triggered KW event happened from ~6 days before to more than 4 days after the IceCube event time (2016-12-10 20:07:16 UT, hereafter T0). Using Konus-Wind waiting mode data in the interval T0 +/- 1000 s, we estimate an upper limit (90% conf.) on the 10 keV – 10 MeV fluence to ~1.2x10^-6 erg/cm^2 for a burst lasting less than 2.944 s and having a typical KW short GRB spectrum (an exponentially cut off power law with alpha =-0.5 and Ep=500 keV, Svinkin et al. 2016). For a typical long GRB spectrum (the Band function with alpha=-1, beta=-2.5, and Ep=250 keV), the corresponding limiting peak flux is ~3.2x10^-7 erg/cm^2/s (10 keV - 10 MeV, 2.944 s scale). All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20267 SUBJECT: IceCube-161210: Kanata/HONIR near-infrared follow-up observation DATE: 16/12/15 07:21:21 GMT FROM: Michitoshi Yoshida at HASC,Hiroshima U Hiroki Mori, Yousuke Utsumi, Yasuyuki T. Tanaka, Koji S. Kawabata, Kensei Shiki, Taisei Abe, Michitoshi Yoshida (Hiroshima University) on behalf of Kanata team We performed J-band tiling observations for the ~40'x40' region centered at the IceCube alert R.A.=46.58 deg and Dec.=14.98 deg (Blaufuss, GCN 20247) with the optical-infrared simultaneous camera HONIR attached to 1.5m Kanata telescope of Hiroshima University from 13 to 17.5 UT on December 11, 2016. Compared our data with 2MASS catalog, we found no bright NIR transient in the observed region. 5 sigma limiting magnitude was J=18.8 (preliminary, 2'' aperture). We also obtained R-band data simultaneously, and the data analysis is ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20269 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-161210 DATE: 16/12/15 16:48:07 GMT FROM: Sara Buson at GSFC/Fermi S. Buson (NASA-GSFC), C.C. Cheung (NRL), D. Kocevski (NASA/MSFC), G. Vianello (Stanford), on behalf of the Fermi-LAT collaboration We report follow-up observations of the very high-energy IceCube-161210 neutrino event (GCN 20247) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2016-12-10 20:06:40 UTC (T0) with J2000 position, RA =46.58 deg, Decl. = 14.98 deg. There are no cataloged >100 MeV gamma-ray sources consistent with the IceCube-161210 localization. The closest gamma-ray source is 3FGL J0250.6+1713, associated with the high-synchrotron peaked flat-spectrum radio quasar, NVSS J025037+171209 (Ackermann et al. 2015 ApJS 810, 14), at a distance of roughly 4 deg and does not show indication of enhanced gamma-ray activity during the 24 hours close to the neutrino detection. The neutrino localization region was outside the LAT field of view at the time of the detection by IceCube. It entered the LAT FoV at ~T0 + 2000 s. We searched for the existence of intermediate (hours to days) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant excess gamma-ray emission (0.1 - 300 GeV) within the I-161210 90% confidence localization. Assuming a power-law spectrum (photon index = 2.2 fixed) for a point source at the IceCube position, the >100 MeV flux upper limits (95% confidence) are < 6.6e-07 ph cm^-2 s^-1 between T0 + 1927 s and T0 + 4413 s (the time interval in which the position of I-161210 entered the LAT field of view for the first time), < 2.7 x 10^-7 ph cm^-2 s^-1 in 24 hours of exposure beginning at T0, and < 3.7 x 10^-8 ph cm^-2 s^-1 in one week of exposure prior to T0. Longer timescale analysis will be made as data become available. Because Fermi operates in an all-sky scanning mode, regular gamma-ray monitoring of this source region will continue. For this source the Fermi LAT contact person is S. Buson (e-mail: sara.buson at nasa.gov). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.