{
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>",
  "eventId": "GRB 250515.65",
  "submittedHow": "email",
  "subject": "MAXI GRB250515.65: Global MASTER-Net observations report",
  "circularId": 40463,
  "bibcode": "2025GCN.40463....1L",
  "createdOn": 1747363925708,
  "body": "V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko, \nG.Antipov,  A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU),\nO.Gress, N.Budnev (ISU),\nC.Francile,  F. Podesta, R.Podesta, E. Gonzalez  (Observatorio Astronomico Felix Aguilar (OAFA),\nA. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),\nA.Sosnovskij (CrAO),\nA. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),\nD.Buckley (SAAO),\nR.Rebolo (The Instituto de Astrofisica de Canarias),\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) \n\nMASTER-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 MAXI GRB250515.65 (trigger No 10849998,21h 14m 24.00s , -80d 30m 00.0s, R=1) errorbox  10 sec after notice time and 40345 sec after trigger time at 2025-05-16 02:41:33 UT, with upper limit up to  19.0 mag. The observations began at zenith distance = 50 deg. The sun  altitude  is -33.6 deg. \n\nMASTER-OAFA robotic telescope  located in Argentina (OAFA observatory of San Juan National University) started inspect of the MAXI GRB250515.65 errorbox  79 sec after notice time and 40414 sec after trigger time at 2025-05-16 02:42:42 UT, with upper limit up to  18.6 mag. The observations began at zenith distance = 61 deg. The sun  altitude  is -62.8 deg. \n\nThe galactic latitude b = -33 deg., longitude l = 312 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2871800\n\nWe obtain a following upper limits.  \n\nTmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n   40376 | 2025-05-16 02:41:33 |         MASTER-SAAO | (21h 16m 32.15s , -80d 50m 43.5s) |   C |    60 | 18.1 |        \n   40436 | 2025-05-16 02:41:33 |         MASTER-SAAO | (21h 16m 32.15s , -80d 50m 43.5s) |   C |   180 | 19.0 |  Coadd \n   40495 | 2025-05-16 02:42:42 |         MASTER-OAFA | (20h 13m 48.68s , -81d 25m 05.7s) |   C |   160 | 17.6 |        \n   40505 | 2025-05-16 02:42:43 |         MASTER-OAFA | (21h 11m 07.77s , -80d 47m 38.7s) |   C |   180 | 18.6 |        \n   40454 | 2025-05-16 02:42:52 |         MASTER-SAAO | (21h 16m 31.94s , -80d 50m 47.8s) |   C |    60 | 18.3 |        \n   40534 | 2025-05-16 02:44:11 |         MASTER-SAAO | (21h 16m 31.62s , -80d 50m 49.7s) |   C |    60 | 18.2 |        \n   40613 | 2025-05-16 02:45:30 |         MASTER-SAAO | (21h 16m 31.26s , -80d 50m 50.6s) |   C |    60 | 18.2 |        \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n"
}