//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24598 SUBJECT: LIGO/Virgo S190519bj: Identification of a GW compact binary merger candidate DATE: 19/05/19 17:09:42 GMT FROM: Roberto De Pietri at LIGO/Virgo The LIGO Scientific Collaboration and the Virgo Collaboration report: We identified the compact binary merger candidate S190519bj during real-time processing of data from LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) at 2019-05-19 15:35:44.398 UTC (GPS time: 1242315362.398). The candidate was found by the PyCBC Live [1], CWB [2], GstLAL [3], MBTAOnline [4], and SPIIR [5] analysis pipelines. S190519bj is an event of interest because its false alarm rate, as determined by the online analysis, is 5.7e-09 Hz, or about one in 5 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S190519bj The classification of the GW signal, in order of descending probability, is BBH (96%), Terrestrial (4%), BNS (<1%), NSBH (<1%), or MassGap (<1%). Assuming the candidate is astrophysical in origin, there is strong evidence against the lighter compact object having a mass < 3 solar masses (HasNS: <1%). Using the masses and spins inferred from the signal, there is strong evidence against matter outside the final compact object (HasRemnant: <1%). One skymap is available at this time and can be retrieved from the GraceDB event page: * bayestar.fits.gz, an updated localization generated by BAYESTAR [6], distributed via GCN notice about 59 minutes after the candidate For the bayestar.fits.gz skymap, the 90% credible region is 967 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 3154 +/- 791 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo Public Alerts User Guide . [1] Nitz et al. PRD 98, 024050 (2018) [2] Klimenko et al. PRD 93, 042004 (2016) [3] Messick et al. PRD 95, 042001 (2017) [4] Adams et al. CQG 33, 175012 (2016) [5] Qi Chu, PhD Thesis, The University of Western Australia (2017) [6] Singer & Price PRD 93, 024013 (2016) Firma il tuo 5 per mille all'Universit? di Parma e aiuta cos? i nostri studenti che vogliono realizzare un'esperienza di studio all'estero - Indica 00308780345 nella tua denuncia dei redditi. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24599 SUBJECT: LIGO/Virgo S190519bj: IceCube Neutrino Search DATE: 19/05/19 17:19:36 GMT FROM: Raamis Hussain at IceCube The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search for track-like muon neutrino events consistent with the sky localization of S190519bj-1-Preliminary in a time range of 1000 seconds centered on the alert event time (2019-05-19 15:27:24.398 UTC to 2019-05-19 15:44:04.398 UTC) during which IceCube was collecting good quality data. No track-like events are found in spatial coincidence with the 90% spatial containment of S190519bj calculated from the map circulated in the preliminary notice. IceCube's sensitivity to point sources within the location spanned by the 90% spatial containment of S190519bj ranges from 0.029 to 0.639 GeV cm^-2 in a 1000 second time window. 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: 24600 SUBJECT: LIGO/Virgo S190519bj: INTEGRAL SPI/ACS prompt observation DATE: 19/05/19 17:25:35 GMT FROM: Enrico Bozzo at ISDC Enrico Bozzo (ISDC/UniGE, Switzerland), Maeve Doyle (UCD, Ireland), V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland) J. Rodi (IAPS-Roma, Italy) A. Coleiro (APC, France) S. Mereghetti (INAF IASF-Milano, Italy) on behalf of the INTEGRAL multi-messenger collaboration: https://www.astro.unige.ch/cdci/integral-multimessenger-collaboration Using INTEGRAL/SPI-ACS realtime data (following Savchenko et al. 2017, A&A 603, A46) we have performed a search for a prompt gamma-ray counterpart of S190519bj (GCN 24598). At the time of the event (2019-05-19 15:35:44 UTC, hereafter T0), INTEGRAL was operating in nominal mode. The peak of the event localization probability was at an angle of 59 deg with respect to the spacecraft pointing axis. This orientation implies strongly suppressed (13% of optimal) response of ISGRI, strongly suppressed (30% of optimal) response of IBIS/Veto, and somewhat suppressed (67% of optimal) response of SPI-ACS. The background within +/-300 seconds around the event was very stable (excess variance 1.2). We have performed a search for any impulsive events in INTEGRAL SPI- ACS (as described in Savchenko et al. 2012, A&A 541A, 122S) data. We do not detect any significant counterparts and estimate a 3-sigma upper limit on the 75-2000 keV fluence of 2.9e-07 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=600 keV) occurring at any time in the interval within 300 s around T0. For a typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and Ep=300 keV), the derived peak flux upper limit is ~2.6e-07 (1.3e-07) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24601 SUBJECT: LIGO/Virgo S190519bj: HAWC follow-up DATE: 19/05/19 17:40:08 GMT FROM: Israel Martinez-Castellanos at UMD/HAWC The HAWC Collaboration (https://www.hawc-observatory.org) reports: The HAWC Collaboration performed a follow-up of the gravitational wave trigger S190519bj (GCN #24598). At the time of the trigger the HAWC local zenith was oriented towards (RA, Dec) = (13.4 deg, 18.9 deg). 77% of the GW candidate sky location probability fell within our observable field of view (0-45 deg zenith angle). We performed a search for a short timescale emission using 6 sliding time windows (dt = 0.3s, 1s, 3s, 10s, 30s and 100s), shifted forward in time by 20% of their width. We searched the 95% probability containment area in a timescale-dependent time period, from t0-5dt to t0+10dt, where t0 is the time of the GW trigger. No significant gamma-ray detection above the background was observed. The sensitivity of this analysis is greatly dependent on zenith angle, ranging from 21.6 deg to 45 deg for the area searched in this analysis. The 5sigma detection sensitivity to a 1s (100s) burst in the 80-800GeV energy range goes from 2.6e-6 erg/cm^2 to 1.1e-4 erg/cm^2 (1.4e-5 erg/cm^2 to 5e-4 erg/cm^2), depending on the zenith angle. HAWC is a TeV gamma ray water Cherenkov array located in the state of Puebla, Mexico. It is sensitive to the energy range ~0.1-100TeV, and monitors 2/3 of the sky every day with an instantaneous field-of-view of ~2 sr. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24602 SUBJECT: LIGO/Virgo S190519bj: ANTARES neutrino search DATE: 19/05/19 18:02:57 GMT FROM: Damien Dornic at CPPM,France M. Ageron (CPPM/CNRS), B. Baret (APC/CNRS), A. Coleiro (APC/Universite Paris Diderot), M. Colomer (APC/Universite Paris Diderot)), D. Dornic (CPPM/CNRS), A. Kouchner (APC/Universite Paris Diderot), T. Pradier (IPHC/Universite de Strasbourg) report on behalf of the ANTARES Collaboration: Using on-line data from the ANTARES detector, we have performed a follow-up analysis of the recently reported LIGO/Virgo S190519bj event using the 90% contour of the bayestar probability map provided by the GW interferometers (GCN#24598). The ANTARES visibility at the time of the alert, together with the 50% and 90% contours of the probability map are shown at https://www.cppm.in2p3.fr/~dornic/events_runo3/S190519bj.png. Considering the location probability provided by the LIGO/Virgo collaborations, there is a 34% chance that the GW emitter was in the ANTARES **upgoing** field of view at the time of the alert. No up-going muon neutrino candidate events were recorded in the ANTARES sky during a +/- 500s time-window centered on the time (2019-05-19 15:35:44 UT) and in the 90% contour of the S190519bj event. The expected number of atmospheric background events in the region visible by ANTARES is 3.6e-4 in the +/- 500s time window. An extended search during +/- 1 hour gives no up-going muon neutrino coincidence. The expected number of atmospheric background events in the region visible by ANTARES is 2.6e-3 in this larger time window. ANTARES is the largest undersea neutrino detector, installed in the Mediterranean Sea, and it is primarily sensitive to neutrinos in the TeV-PeV energy range. At 10 TeV, the median angular resolution for muon neutrinos is about 0.5 degrees. In the range 1-100 TeV ANTARES has a competitive sensitivity to this position in the sky. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24603 SUBJECT: LIGO/Virgo S190519bj: AGILE MCAL observations DATE: 19/05/19 18:17:18 GMT FROM: Fabrizio Lucarelli at SSDC/INAF-OAR F.Lucarelli (SSDC, and INAF/OAR), M.Cardillo (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), C.Casentini, G.Piano, A.Ursi (INAF/IAPS), C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste) report on behalf of the AGILE Team: In response to the LIGO-Virgo GW event S190519bj at T0 = 2019-05-19 15:35:44 (UT), a preliminary analysis of the AGILE minicalorimeter (MCAL) triggered data found no event candidates within a time interval covering +/- 100 sec from the LIGO-Virgo T0. Three-sigma upper limits (ULs) are obtained for a 1 s integration time at different celestial positions within the accessible S190519bj 90% c.l. localization region (almost 70% of the given GW contour), from a minimum of 1.16E-06 erg cm^-2 to a maximum of 1.90E-06 erg cm^-2 (assuming as spectral model a single power law with photon index 1.5). The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24604 SUBJECT: LIGO-Virgo S190519bj: AGILE GRID observations DATE: 19/05/19 19:36:35 GMT FROM: Francesco Verrecchia at ASDC F. Verrecchia, F. Lucarelli (SSDC, and INAF-OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS), C. Pittori (SSDC, and INAF-OAR), C. Casentini, G. Piano A. Ursi (INAF/IAPS), A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste), report on behalf of the AGILE Team: In response to the LIGO-Virgo GW event S190519bj at T0 = 2019-05-19 15:35:44.40 UTC (GCN #24598) a preliminary analysis of the AGILE exposure at T0 showed that about 70% of the S190517h 90% c.l. localization region (LR) was exposed by the Gamma-Ray Imaging Detector (GRID) at off-axis angles between 20 and 70 deg. We performed an analysis of the GRID data in the energy range 50 MeV - 10 GeV over three time intervals before and after T0, where good exposure of the S190519bj 90% c.l. LR was available. The following preliminary GRID 3-sigma upper limit (UL) values are obtained over a large area of the exposed LR: (T0-2s; T0+2s ): from 7.9e-07 to 3.4e-06 erg cm^-2 s^-1; (T0; T0+10s ): from 3.1e-07 to 1.3e-06 erg cm^-2 s^-1; (T0; T0+100s): from 3.1e-08 to 9.5e-08 erg cm^-2 s^-1. An image of the AGILE-GRID 100s exposure near T0 is available at the site https://tools.ssdc.asi.it/ImgView/Agile/S190519bj_T0_d100s_fv70a75E50d11 These measurements were obtained with AGILE observing a large portion of the sky in spinning mode. Additional analysis of AGILE data is in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24605 SUBJECT: LIGO/Virgo S190519bj: Fermi GBM Observations DATE: 19/05/19 20:05:57 GMT FROM: Suraj Poolakkil at UAH S. Poolakkil (UAH) and R. Hamburg (UAH) report on behalf of the Fermi-GBM Team and the GBM-LIGO/Virgo group: For S190519bj, and using the initial BAYESTAR skymap, Fermi-GBM was observing 32.0% of the localization probability at event time. There was no Fermi-GBM onboard trigger around the event time of the LIGO/Virgo detection of GW trigger S190519bj (GCN 24598). An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM also identified no counterpart candidates. The GBM targeted search, the most sensitive, coherent search for GRB-like signals, was run from +/-30 s around merger time, and also identified no counterpart candidates. Part of the LVC localization region is behind the Earth for Fermi, located at RA = 53.1 and Dec = 15.4 with a radius of 67.5 degrees. We therefore set upper limits on impulsive gamma-ray emission. Using the representative soft, normal, and hard GRB-like spectral templates described in arXiv:1612.02395, we set the following 3 sigma flux upper limits over 10-1000 keV, weighted by the remaining visible GW localization probability (in units of erg/s/cm^2): Timescale soft norm hard -------------------------------------- 0.128 s: 1.3e-07 2.1e-07 4.6e-07 1.024 s: 3.9e-08 6.2e-08 1.4e-07 8.192 s: 1.4e-08 1.6e-08 3.8e-08 Assuming the median luminosity distance of ~3154 Mpc from the GW detection, we estimate intrinsic luminosity upper limits of (2.6-24.3)E49 erg/s for the soft template, (2.5-34.0)E49 erg/s for the normal template, and (1.0-12.6)E50 erg/s for the hard template over the 1 keV-10 MeV energy range. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24607 SUBJECT: LIGO/Virgo S190519bj Global MASTER-Net observations report DATE: 19/05/19 22:24:13 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko (Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University) A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory) K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk (Irkutsk State University) V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University, Blagoveschensk) R. Podesta, Carlos Lopez and F. Podesta (Observatorio Astronomico Felix Aguilar (OAFA)) Hugo Levato and Carlos Saffe (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias) D. Buckley, S. Potter, A. Kniazev, M. Kotze (South African Astronomical Observatory) MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the LIGO/Virgo S190519bj errorbox 8823 sec after trigger time at 2019-05-19 18:02:47 UT, with upper limit up to 18.8 mag. The observations began at zenit distance = 146 deg. The sun altitude is -28.4 deg. MASTER-Tavrida robotic telescope located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the LIGO/Virgo S190519bj errorbox 9382 sec after trigger time at 2019-05-19 18:12:06 UT, with upper limit up to 17.4 mag. Observations started at twilight. The observations began at zenit distance = 136 deg. The sun altitude is -10.6 deg. MASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the LIGO/Virgo S190519bj errorbox 17957 sec after trigger time at 2019-05-19 20:35:01 UT, with upper limit up to 16.5 mag. The observations began at zenit distance = 119 deg. The sun altitude is -26.8 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/ligo_1.php?id=10404 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 8913 | 2019-05-19 18:02:47 | MASTER-SAAO | ( 12h 17m 25.50s , -21d 44m 22.80s) | C | 180 | 18.0 | 9472 | 2019-05-19 18:12:06 | MASTER-Tavrida | ( 0h 33m 00.96s , +55d 58m 47.18s) | C | 180 | 13.7 | 9708 | 2019-05-19 18:16:01 | MASTER-SAAO | ( 12h 17m 27.15s , -21d 44m 33.27s) | C | 180 | 18.1 | 9710 | 2019-05-19 18:16:04 | MASTER-Tavrida | ( 0h 33m 35.51s , +55d 37m 44.92s) | C | 180 | 14.1 | 9947 | 2019-05-19 18:20:01 | MASTER-Tavrida | ( 23h 53m 25.12s , +56d 1m 04.88s) | C | 180 | 12.3 | 9949 | 2019-05-19 18:20:03 | MASTER-SAAO | ( 12h 26m 03.31s , -21d 44m 32.02s) | C | 180 | 18.2 | 10174 | 2019-05-19 18:23:47 | MASTER-SAAO | ( 12h 26m 03.47s , -21d 44m 55.35s) | C | 180 | 18.0 | 10411 | 2019-05-19 18:27:44 | MASTER-SAAO | ( 12h 34m 41.98s , -21d 44m 33.85s) | C | 180 | 17.8 | 10422 | 2019-05-19 18:27:55 | MASTER-Tavrida | ( 0h 24m 55.69s , +59d 56m 15.11s) | C | 180 | 15.9 | 10422 | 2019-05-19 18:27:55 | MASTER-Tavrida | ( 0h 37m 19.98s , +59d 53m 23.31s) | C | 180 | 15.4 | 10660 | 2019-05-19 18:31:54 | MASTER-Tavrida | ( 0h 25m 12.80s , +59d 43m 54.13s) | C | 180 | 15.8 | 10665 | 2019-05-19 18:31:59 | MASTER-SAAO | ( 12h 26m 03.78s , -21d 44m 42.72s) | C | 180 | 18.1 | 10927 | 2019-05-19 18:36:21 | MASTER-SAAO | ( 12h 26m 03.96s , -21d 45m 07.00s) | C | 180 | 17.9 | 11134 | 2019-05-19 18:39:47 | MASTER-Tavrida | ( 0h 25m 11.44s , +59d 43m 35.13s) | C | 180 | 15.8 | 11192 | 2019-05-19 18:40:45 | MASTER-SAAO | ( 12h 34m 42.17s , -21d 45m 05.76s) | C | 180 | 17.5 | 11371 | 2019-05-19 18:43:44 | MASTER-Tavrida | ( 23h 53m 15.48s , +57d 57m 23.33s) | C | 180 | 12.5 | 11371 | 2019-05-19 18:43:44 | MASTER-Tavrida | ( 0h 4m 59.51s , +57d 55m 17.17s) | C | 180 | 12.8 | 11608 | 2019-05-19 18:47:42 | MASTER-Tavrida | ( 0h 5m 24.49s , +57d 37m 26.05s) | C | 180 | 12.7 | 11608 | 2019-05-19 18:47:42 | MASTER-Tavrida | ( 23h 53m 40.99s , +57d 43m 55.74s) | C | 180 | 12.6 | 12082 | 2019-05-19 18:55:36 | MASTER-Tavrida | ( 0h 5m 23.76s , +57d 37m 03.52s) | C | 180 | 12.3 | 12082 | 2019-05-19 18:55:36 | MASTER-Tavrida | ( 23h 53m 39.76s , +57d 43m 35.66s) | C | 180 | 13.1 | 12320 | 2019-05-19 18:59:34 | MASTER-Tavrida | ( 23h 53m 16.49s , +57d 57m 10.06s) | C | 180 | 12.9 | 12321 | 2019-05-19 18:59:34 | MASTER-Tavrida | ( 0h 5m 01.04s , +57d 54m 56.60s) | C | 180 | 12.7 | 12800 | 2019-05-19 19:07:33 | MASTER-Tavrida | ( 23h 53m 02.52s , +59d 54m 59.97s) | C | 180 | 16.9 | 12800 | 2019-05-19 19:07:33 | MASTER-Tavrida | ( 0h 5m 28.59s , +59d 52m 44.68s) | C | 180 | 16.4 | 13039 | 2019-05-19 19:11:33 | MASTER-Tavrida | ( 0h 5m 44.78s , +59d 37m 04.93s) | C | 180 | 16.4 | 13039 | 2019-05-19 19:11:33 | MASTER-Tavrida | ( 23h 53m 17.71s , +59d 43m 31.30s) | C | 180 | 17.2 | 13519 | 2019-05-19 19:19:32 | MASTER-Tavrida | ( 0h 5m 46.78s , +59d 37m 27.98s) | C | 180 | 15.1 | 13519 | 2019-05-19 19:19:33 | MASTER-Tavrida | ( 23h 53m 19.03s , +59d 43m 52.77s) | C | 180 | 17.4 | 13758 | 2019-05-19 19:23:32 | MASTER-Tavrida | ( 23h 53m 03.08s , +59d 54m 49.86s) | C | 180 | 17.2 | 13758 | 2019-05-19 19:23:32 | MASTER-Tavrida | ( 0h 5m 29.76s , +59d 52m 30.33s) | C | 180 | 15.0 | 13995 | 2019-05-19 19:27:29 | MASTER-Tavrida | ( 23h 54m 16.84s , +53d 43m 35.75s) | C | 180 | 13.4 | 14229 | 2019-05-19 19:31:23 | MASTER-Tavrida | ( 23h 17m 27.53s , +51d 59m 52.67s) | C | 180 | 12.0 | 14463 | 2019-05-19 19:35:16 | MASTER-Tavrida | ( 0h 23m 47.65s , +57d 43m 55.97s) | C | 180 | 13.5 | 14571 | 2019-05-19 19:37:05 | MASTER-SAAO | ( 12h 43m 20.00s , -21d 45m 36.52s) | C | 180 | 18.4 | 14697 | 2019-05-19 19:39:11 | MASTER-Tavrida | ( 0h 23m 22.55s , +57d 57m 20.43s) | C | 180 | 14.4 | 14697 | 2019-05-19 19:39:11 | MASTER-Tavrida | ( 0h 35m 07.20s , +57d 55m 07.82s) | C | 180 | 13.7 | 14791 | 2019-05-19 19:40:44 | MASTER-SAAO | ( 12h 45m 59.50s , -23d 45m 59.09s) | C | 180 | 18.4 | 14937 | 2019-05-19 19:43:11 | MASTER-Tavrida | ( 23h 17m 59.96s , +51d 43m 37.96s) | C | 180 | 14.5 | 15009 | 2019-05-19 19:44:22 | MASTER-SAAO | ( 12h 23m 01.40s , -25d 46m 02.26s) | C | 180 | 18.4 | 15235 | 2019-05-19 19:48:09 | MASTER-SAAO | ( 12h 43m 20.89s , -21d 45m 51.96s) | C | 180 | 18.7 | 15453 | 2019-05-19 19:51:46 | MASTER-SAAO | ( 12h 45m 59.50s , -23d 46m 11.77s) | C | 180 | 18.3 | 15666 | 2019-05-19 19:55:19 | MASTER-SAAO | ( 12h 54m 45.88s , -23d 46m 09.23s) | C | 180 | 18.3 | 15883 | 2019-05-19 19:58:56 | MASTER-SAAO | ( 12h 23m 01.85s , -25d 46m 20.96s) | C | 180 | 18.5 | 16099 | 2019-05-19 20:02:33 | MASTER-SAAO | ( 12h 31m 53.93s , -25d 46m 15.85s) | C | 180 | 18.3 | 16325 | 2019-05-19 20:06:18 | MASTER-SAAO | ( 12h 54m 44.76s , -23d 46m 21.59s) | C | 180 | 18.4 | 16562 | 2019-05-19 20:10:16 | MASTER-SAAO | ( 13h 6m 13.80s , -33d 45m 51.77s) | C | 180 | 18.2 | 16742 | 2019-05-19 20:10:16 | MASTER-SAAO | ( 13h 6m 13.80s , -33d 45m 51.78s) | C | 540 | 18.8 | Coadd 16786 | 2019-05-19 20:13:59 | MASTER-SAAO | ( 13h 6m 12.54s , -33d 45m 56.95s) | C | 180 | 18.0 | 17050 | 2019-05-19 20:18:24 | MASTER-SAAO | ( 12h 31m 54.55s , -25d 46m 58.91s) | C | 180 | 17.9 | 17280 | 2019-05-19 20:22:14 | MASTER-SAAO | ( 13h 6m 14.23s , -33d 46m 40.08s) | C | 180 | 17.9 | 17543 | 2019-05-19 20:26:36 | MASTER-SAAO | ( 13h 6m 14.46s , -33d 46m 26.60s) | C | 180 | 17.6 | 17768 | 2019-05-19 20:30:21 | MASTER-SAAO | ( 13h 15m 50.91s , -33d 46m 25.90s) | C | 180 | 17.6 | 17984 | 2019-05-19 20:33:58 | MASTER-SAAO | ( 13h 5m 56.01s , -35d 46m 59.51s) | C | 180 | 17.6 | 18047 | 2019-05-19 20:35:01 | MASTER-Kislovodsk | ( 23h 48m 12.35s , +48d 0m 27.92s) | C | 180 | 15.6 | 18047 | 2019-05-19 20:35:01 | MASTER-Kislovodsk | ( 0h 0m 10.60s , +47d 31m 59.93s) | C | 180 | 15.9 | 18206 | 2019-05-19 20:37:39 | MASTER-SAAO | ( 13h 5m 56.16s , -35d 46m 46.28s) | C | 180 | 17.3 | 18260 | 2019-05-19 20:38:33 | MASTER-Kislovodsk | ( 22h 39m 05.64s , +36d 3m 13.81s) | C | 180 | 16.5 | 18260 | 2019-05-19 20:38:33 | MASTER-Kislovodsk | ( 22h 48m 59.75s , +35d 34m 26.35s) | C | 180 | 16.2 | 18434 | 2019-05-19 20:41:28 | MASTER-SAAO | ( 13h 15m 51.32s , -33d 46m 45.13s) | C | 180 | 17.4 | 18658 | 2019-05-19 20:45:12 | MASTER-SAAO | ( 13h 5m 55.00s , -35d 47m 15.98s) | C | 180 | 17.1 | 18878 | 2019-05-19 20:48:52 | MASTER-SAAO | ( 13h 5m 56.59s , -35d 47m 20.57s) | C | 180 | 17.1 | 19099 | 2019-05-19 20:52:32 | MASTER-SAAO | ( 13h 15m 48.77s , -35d 46m 57.35s) | C | 180 | 17.8 | 19279 | 2019-05-19 20:52:32 | MASTER-SAAO | ( 13h 15m 48.78s , -35d 46m 57.40s) | C | 540 | 18.1 | Coadd 19319 | 2019-05-19 20:56:13 | MASTER-SAAO | ( 13h 25m 39.53s , -35d 47m 15.36s) | C | 180 | 17.9 | 19533 | 2019-05-19 20:59:47 | MASTER-SAAO | ( 13h 25m 31.36s , -33d 47m 00.80s) | C | 180 | 17.9 | 19750 | 2019-05-19 21:03:24 | MASTER-SAAO | ( 13h 15m 47.90s , -35d 47m 11.11s) | C | 180 | 17.5 | 19962 | 2019-05-19 21:06:55 | MASTER-SAAO | ( 13h 15m 48.03s , -35d 47m 36.71s) | C | 180 | 17.3 | 20179 | 2019-05-19 21:10:33 | MASTER-SAAO | ( 13h 25m 41.65s , -35d 47m 34.27s) | C | 180 | 17.0 | 20397 | 2019-05-19 21:14:10 | MASTER-SAAO | ( 13h 35m 33.86s , -35d 47m 12.23s) | C | 180 | 17.9 | 20577 | 2019-05-19 21:14:10 | MASTER-SAAO | ( 13h 35m 33.86s , -35d 47m 12.23s) | C | 540 | 17.6 | Coadd 20612 | 2019-05-19 21:17:46 | MASTER-SAAO | ( 13h 25m 30.97s , -33d 47m 24.55s) | C | 180 | 17.3 | 20835 | 2019-05-19 21:21:28 | MASTER-SAAO | ( 13h 35m 08.88s , -33d 47m 37.26s) | C | 180 | 16.9 | 21059 | 2019-05-19 21:25:12 | MASTER-SAAO | ( 13h 35m 34.37s , -35d 47m 47.89s) | C | 180 | 16.4 | 21289 | 2019-05-19 21:29:02 | MASTER-SAAO | ( 13h 35m 34.47s , -35d 47m 31.21s) | C | 180 | 15.8 | 21516 | 2019-05-19 21:32:50 | MASTER-SAAO | ( 13h 35m 09.26s , -33d 47m 31.91s) | C | 180 | 16.6 | 21783 | 2019-05-19 21:37:16 | MASTER-SAAO | ( 13h 7m 30.54s , -31d 48m 14.69s) | C | 180 | 16.5 | 21963 | 2019-05-19 21:37:16 | MASTER-SAAO | ( 13h 7m 30.54s , -31d 48m 14.77s) | C | 540 | 16.9 | Coadd 22034 | 2019-05-19 21:41:28 | MASTER-SAAO | ( 13h 7m 30.57s , -31d 48m 01.21s) | C | 180 | 16.4 | 22255 | 2019-05-19 21:45:09 | MASTER-SAAO | ( 12h 48m 38.76s , -31d 48m 47.81s) | C | 180 | 16.2 | 22483 | 2019-05-19 21:48:57 | MASTER-SAAO | ( 13h 7m 30.69s , -31d 48m 31.88s) | C | 180 | 16.1 | 22695 | 2019-05-19 21:52:28 | MASTER-SAAO | ( 13h 7m 30.75s , -31d 48m 17.21s) | C | 180 | 15.6 | 22798 | 2019-05-19 21:54:12 | MASTER-Kislovodsk | ( 23h 15m 14.23s , +44d 4m 01.10s) | C | 180 | 14.9 | 22798 | 2019-05-19 21:54:12 | MASTER-Kislovodsk | ( 23h 26m 28.09s , +43d 35m 29.03s) | C | 180 | 12.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24609 SUBJECT: LIGO/Virgo S190519bj: MAXI/GSC Observations DATE: 19/05/20 02:53:58 GMT FROM: Motoko Serino at RIKEN/MAXI N. Kawai, M. Sugizaki (Tokyo Tech), H. Negoro (Nihon U.), S. Sugita, M. Serino (AGU), M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), S. Nakahira, T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, H. Nishida, A. Yoshida (AGU), Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.), M. Shidatsu (Ehime U.), M. Oeda, K. Shiraishi (Tokyo Tech), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai, M. Tominaga (JAXA), Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake (Kyoto U.), H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.), M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU) report on behalf of the MAXI team: We examined MAXI/GSC all-sky X-ray images (2-20 keV) after the LVC trigger S190519bj at 2019-05-19 15:35:44.398 UTC (GCN 24598). At the trigger time of S190519bj, the high-voltage of MAXI/GSC was off, and it was turned on at T0+422 sec (=T0+7.0 min). The first one-orbit (92 min) scan observation with GSC after the event covered 93% of the 90% credible region of the bayestar skymap from 15:42:46 to 16:47:22 UTC (T0+422 to T0+4298 sec). No significant new source was found in the region in the one-orbit scan observation. A typical 1-sigma averaged upper limit obtained in one scan observation is 20 mCrab at 2-20 keV. If you require information about X-ray flux by MAXI/GSC at specific coordinates, please contact the submitter of this circular by email. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24610 SUBJECT: LIGO/Virgo S190519bj: Swift/BAT Counterpart Search DATE: 19/05/20 03:09:03 GMT FROM: Amy Lien at GSFC D. M. Palmer (LANL), S. D. Barthelmy (NASA/GSFC), A. Y. Lien (GSFC/UMBC), T. Sakamoto (AGU), A. A. Breeveld (MSSL-UCL), A. P. Beardmore (U. Leicester), D. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC), G. Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB), V. D'Elia(ASDC), S. Emery (UCL-MSSL), P. A. Evans (U. Leicester), P. Giommi (ASI), C. Gronwall (PSU), D. Hartmann (Clemson U.), J. A. Kennea (PSU), H. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), J. A. Nousek (PSU), S. R. Oates (Uni. of Warwick), P. T. O'Brien (U. Leicester), J. P. Osborne (U. Leicester), C. Pagani (U. Leicester), K. L. Page (U.Leicester), M. Perri (ASDC), J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU), G. Tagliaferri (INAF-OAB), A. Tohuvavohu (PSU), E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team: We report the search results in the BAT data within T0 +/- 100 s of the LVC event S190519bj (LIGO/VIRGO Collaboration GCN Circ. 24598), where T0 is the LVC trigger time (2019-05-19T15:35:44.398 UTC). The center of the BAT FOV at T0 is RA = 99.994 deg, DEC = -0.010 deg, ROLL = 296.994 deg. The BAT Field of View (>10% partial coding) covers 0.00% of the integrated LVC localization probability, and 0.00% of the galaxy convolved probability (Evans et al. 2016). Within T0 +/- 100 s, no significant detections (signal-to-noise ratio >~ 5 sigma) are found in the BAT raw light curves with time bins of 64 ms, 1 s, and 1.6 s. Also, the larger fluctuation seen in the raw light curve is likely due to the proximity to the SAA around that time. Assuming an on-axis (100% coded) short GRB with a typical spectrum in the BAT energy range (i.e., a simple power-law model with a power-law index of -1.32, Lien & Sakamoto et al. 2016), the 5-sigma upper limit in the 1-s binned light curve corresponds to a flux upper limit (15-350 keV) of ~ 9.82 x 10^-8 erg/s/cm^2. No event data are available at this point. BAT retains decreased, but significant, sensitivity to rate increases for gamma-ray events outside of its FOV. About 88.21% of the integrated LVC localization probability was outside of the BAT FOV but above the Earth's limb from Swift's location, and the corresponding flux upper limits for this region are within roughly an order of magnitude higher than those within the FOV. The results of the BAT analysis are available at https://swift.gsfc.nasa.gov/results/BATbursts/team_web/S190519bj/web/source.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24616 SUBJECT: LIGO/Virgo S190519bj: Upper limits from Insight-HXMT/HE observations DATE: 19/05/21 03:16:05 GMT FROM: Shuo Xiao at IHEP S. Xiao, C. Cai, Q. B. Yi, Q. Luo, C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, M. Wu, Y. P. Xu, S. N. Zhang (IHEP), report on behalf of the Insight-HXMT team: Insight-HXMT was taking data normally around the reported LIGO/Virgo S190519bj event (GCN #24598), trigger time 2019-05-19T15:35:44.398 UTC. At T0, more than 50% of the LIGO localization region was covered by Insight-HXMT without occultation by the Earth. Within T0 +/- 100 s, no significant excess events (SNR > 3 sigma) are found in a search of the Insight-HXMT/HE raw light curves. Assuming the GW counterpart GRB with three typical GRB Band spectral models, two typical duration timescales (1 s, 10 s) from the peak position of the LIGO-Virgo location probability map, the 5-sigma upper-limits fluence (0.2 - 5 MeV, incident energy) are reported below: Band model 1 (alpha=-1.9, beta=-3.7, Ep=70 keV): 1 s: 1.1e-07 erg cm^-2 10 s: 3.8e-07 erg cm^-2 Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV): 1 s: 1.6e-07 erg cm^-2 10 s: 6.0e-07 erg cm^-2 Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV): 1 s: 4.2e-07 erg cm^-2 10 s: 1.3e-06 erg cm^-2 All measurements above are made with the CsI detectors operating in the regular mode with the energy range of about 80-800 keV (deposited energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the spacecraft. Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information could be found at: http://www.hxmt.org. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24627 SUBJECT: LIGO/Virgo S190519bj: Fermi-LAT search for a high-energy gamma-ray counterpart DATE: 19/05/21 07:27:11 GMT FROM: Magnus Axelsson at Stockholm U. M. Axelsson (KTH and Stockholm Univ.), N.Omodei (Stanford Univ.), D.Kocevski (NASA/MSFC) and F. Longo (Univ. and INFN Trieste) report on behalf of the Fermi-LAT Collaboration: We have searched data collected by the Fermi Large Area Telescope (LAT) on May 19, 2019, for possible high-energy (E > 100 MeV) gamma-ray emission in spatial/temporal coincidence with the LIGO/Virgo trigger S190519bj (GCN 24598). We define "instantaneous coverage" as the integral over the region of the LIGO probability map that is within the LAT field of view at a given a time, and "cumulative coverage" as the integral of the instantaneous coverage over time. Fermi-LAT had instantaneous coverage of ~20% of the LIGO probability at the time of the trigger (T0 = 2019-05-19 15:35:44.398 UTC), and reached 100% cumulative coverage after ~4.6ks. We performed a search for a transient counterpart within the observed region of the 90% contour of the LIGO map in a fixed time window from T0 to T0 + 10 ks. No significant excess was found. We also performed a search which adapted the time interval of the analysis to the exposure of each region of the sky, and no additional excesses were found. Energy flux upper bounds for the fixed time interval between 100 MeV and 1 GeV for this search vary between 6.5e-10 and 2.1e-09 [erg/cm^2/s]. The Fermi-LAT point of contact for this event is Magnus Axelsson (magaxe@kth.se). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 24668 SUBJECT: LIGO/Virgo S190519bj: AstroSat CZTI upper limits DATE: 19/05/28 06:14:50 GMT FROM: Varun Bhalerao at Indian Inst of Tech A. Anumarlapudi (IITB), D. Saraogi (IITB), Aarthy E. (PRL), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: We have carried a search for X-ray candidates in Astrosat CZTI data in a 100 sec window around the trigger time of the BBH merger event S190519bj (UTC 2019-05-19 15:35:44.000, GraceDB event). CZTI is a coded aperture mask instrument that has considerable effective area for about 29% of the entire sky, but is also sensitive to brighter transients from the entire sky. At the time of merger, Astrosat's nominal pointing is (RA=332.85, DEC=18.08), which is 87.51 deg away from the maximum probability location. In time a interval of 100 sec around the event, 72% of the sky locations are visible and not occulted by Earth in satellite's frame and the rest 28% with the inclusion of maximum probaility location are occulted. CZTI data were de-trended to remove orbit-wise background variation. We then searched data from three of the four independent, identical quadrants to look for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in count rates were estimated by using data from 10 (+-5) neighbouring orbits. We selected confidence levels such that the probability of a false trigger in a 1000 sec window is 10^-4.We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV. We convert our count rates into flux by assuming that the source spectrum is a power law with alpha = -1.0. We use a detailed mass model of the satellite to calculate the instrument response for every htm grid point that fall in 90% LIGO localization region and calculate flux limit in that direction. We get the following upper limits for source flux in the 20-200 keV band by taking a probability weighted mean of flux limit and are reported here : 0.1 s: flux limit= 4.6 e-7 ergs/cm^2/s 1.0 s: flux limit= 1.8 e-6 ergs/cm^2/s 10.0 s: flux limit= 2.8 e-6 ergs/cm^2/s CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.