//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25502 SUBJECT: GRB 190828A: MAXI/GSC detection DATE: 19/08/28 08:44:15 GMT FROM: Satoshi Sugita at Aoyama Gakuin U. S. Sugita, H. Nishida, M. Serino (AGU), H. Negoro (Nihon U.), K. Asakura (Osaka U.), M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, A. Yoshida (AGU), W. Iwakiri, Y. Tsuboi, R. Sasaki, H. Kawai, T. Sato (Chuo U.), M. Shidatsu (Ehime U.), N. Kawai, M. Sugizaki, M. Oeda, K. Shiraishi (Tokyo Tech), S. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, 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, 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: The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 07:58:01 UT on 2019 August 28. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (58.011 deg, 46.448 deg) = (03 52 02, +46 26 52) (J2000) with a 90% C.L. statistical error of 0.25 deg and an additional systematic uncertainty of 0.1 deg (90% containment radius). Without assumptions on the source constancy, we obtain a rectangular error box for the transient source with the following corners: (56.303, 46.041) deg = (03 45 12, +46 02 27) (J2000) (56.644, 45.605) deg = (03 46 34, +45 36 17) (J2000) (60.044, 46.816) deg = (04 00 10, +46 48 57) (J2000) (59.724, 47.262) deg = (03 58 53, +47 15 43) (J2000) The X-ray flux averaged over the scan was 193 +- 27 mCrab (4.0-10.0keV, 1 sigma error). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25518 SUBJECT: Swift GRB190828.54 Global MASTER-Net observations report DATE: 19/08/28 13:55:10 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB190828.54 (trigger No 922808,16h 47m 16.320s , +27d 14m 13.20s, R=0.05) errorbox 648 sec after notice time and 674 sec after trigger time at 2019-08-28 13:11:13 UT, with upper limit up to 19.4 mag. Observations started at twilight. The observations began at zenit distance = 31 deg. The sun altitude is -10.6 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/observ.php?id=1118074 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 734 | MASTER-Tunka | P| | 120 | 18.4 | 734 | MASTER-Tunka | P- | 120 | 16.8 | 1189 | MASTER-Tunka | P| | 180 | 19.3 | 1189 | MASTER-Tunka | P- | 180 | 17.4 | 1491 | MASTER-Tunka | P| | 180 | 19.4 | 1491 | MASTER-Tunka | P- | 180 | 17.8 | The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25527 SUBJECT: Integral GRB190828.78 Global MASTER-Net observations report DATE: 19/08/28 19:39:17 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) 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) was pointed to the Integral GRB190828.78 (trigger No 8364,16h 48m 51.120s , -24d 35m 06.00s, R=0.0516667) errorbox 20 sec after notice time and 31 sec after trigger time at 2019-08-28 18:49:11 UT, with upper limit up to 19.2 mag. The observations began at zenit distance = 25 deg. The sun altitude is -32.4 deg. MASTER-Tavrida robotic telescope located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Integral GRB190828.78 errorbox 30 sec after notice time and 41 sec after trigger time at 2019-08-28 18:49:21 UT, with upper limit up to 16.3 mag. The observations began at zenit distance = 78 deg. The sun altitude is -23.3 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/observ.php?id=1118498 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 37 | MASTER-SAAO | P\ | 10 | 17.2 | 52 | MASTER-SAAO | P\ | 40 | 18.0 | Coadd 46 | MASTER-Tavrida | C | 10 | 15.9 | 61 | MASTER-Tavrida | C | 40 | 16.3 | Coadd 63 | MASTER-SAAO | P\ | 10 | 17.1 | 80 | MASTER-Tavrida | C | 10 | 15.6 | 93 | MASTER-SAAO | P\ | 20 | 17.7 | 119 | MASTER-Tavrida | C | 20 | 16.0 | 130 | MASTER-SAAO | P\ | 20 | 17.8 | 165 | MASTER-SAAO | P\ | 90 | 18.6 | Coadd 171 | MASTER-SAAO | P\ | 30 | 18.0 | 222 | MASTER-SAAO | P\ | 40 | 18.3 | 283 | MASTER-SAAO | P\ | 50 | 18.4 | 353 | MASTER-SAAO | P\ | 190 | 19.1 | Coadd 354 | MASTER-SAAO | P\ | 60 | 18.6 | 680 | MASTER-SAAO | P\ | 370 | 19.2 | Coadd Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25529 SUBJECT: GRB 190828A: Tiled Swift observations DATE: 19/08/28 21:25:46 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the MAXI GRB 190828A. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00086 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the MAXI event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25542 SUBJECT: GRB 190828A: Swift-XRT observations DATE: 19/08/29 09:46:09 GMT FROM: Paolo D'Avanzo at INAF - OAB J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), B. Sbarufatti (PSU), D.N. Burrows (PSU) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the MAXI-detected burst GRB 190828A (Sugita et al. GCN Circ. 25502) in a series of observations tiled on the sky. The total exposure time is 1.3 ks, distributed over 7 tiles; the maximum exposure at a single sky location was 393 s. The data were collected between T0+48.4 ks and T0+49.8 ks, and are entirely in Photon Counting (PC) mode. No X-ray sources have been detected. The 3-sigma upper limit in the field (not including the regions where the tiles overlap) ranges from ~0.02 to ~0.15 ct s^-1, corresponding to a 0.3-10 keV observed flux of 9.9e-13 to 5.8e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum). The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00086. This circular is an official product of the Swift-XRT team.