{
  "eventId": "IceCube-260315A",
  "editedOn": 1773947899056,
  "bibcode": "2026GCN.44023....1S",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>",
  "editedBy": "Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Vladimir Lipunov at Lomonosov Moscow State University <lipunov@sai.msu.ru>",
  "subject": "IceCube Alert-260315A/AT2026fpm Automatic MASTER optical blue counterpart  candidate",
  "createdOn": 1773599986399,
  "format": "text/plain",
  "body": "\nM.J. Segura, C.Francile,  F. Podesta, R.Podesta, E. Gonzalez (Observatorio\nAstronomico Felix Aguilar (OAFA),\nYa.Kechin, V.Lipunov (Lomonosov MSU), N.Budnev, O.Gress (ISU),\nA.Kuznetsov, I.Panchenko, P.Balanutsa, G.Antipov, E.Gorbovskoy, N.Tiurina,\nV.Senik, A.Chasovnikov, M.Shilova,V.Topolev, D.Vlasenko, A.Sankovich,\nYu.Tselik (Lomonosov MSU),\nD.Svinkin (Ioffe Institute),\nA. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),\nA.Sosnovskij (CrAO),\nD.Buckley (SAAO),\nR.Rebolo (The Instituto de Astrofisica de Canarias),\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez,\nJ.Martinez,A.R.Corella, J.Tanori, L. Villalobos, L.H.Rodriguez (INAOE, Guillermo\nHaro Astrophysics Observatory)\nA. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)\n\nMASTER OT J114437.99-023613.5/AT 2026fpm discovery\n\nMASTER-OAFA robotic telescope  [1]  located in Argentina (OAFA observatory of San Juan National University) was pointed to the IceCube Alert 260315A (trigger No 46886533,11h 42m 40.32s , -01d 53m 06.0s, R=0.71) errorbox 105 sec after notice time and 224 sec after trigger time at 2026-03-15 02:22:50 UT, with upper limit up to  20.4 mag. The observations began at zenith distance = 45 deg. The sun  altitude  is -42.8 deg.\n\nThe galactic latitude b = 57 deg., longitude l = 272 deg.\n\nReal time updated cover map and OT discovered available here:\nhttps://master.sai.msu.ru/site/master2/observ.php?id=3187113\n\nMASTER-OAFA auto-detection system [4]\ndiscovered OT source at (RA, Dec) = 11h 44m 37.99s -02d 36m 13.5s on 2026-03-15.10943 UT very close to center of neutrino errorbox (GCN Circular #44017).\n\nThe OT magnitude in 'CLEAR' filter is 19.2m\n(mlim = 20.0).\n\nThe OT is seen in 44 images. There is no minor planet at this place.\n\nWe have reference image on 2026-02-12.28608 UT with unfiltered mlim=19.9m.\n\nSpectral observations are required.\n\nThe discovery and reference images are available at:\n\nhttp://master.sai.msu.ru/static/OT/114437.99-023613.5.png\n\n[1] Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L\n[2] Lipunov et al. 2022, Universe, Vol. 8(5), id.271\n[3] Lipunov et a. 2019, ARep, vol.63, 293\n[4] Lipunov et al. 2023, Astronomical Robotic Networks and Operative Multichanel\nAstrophysics,Lomonosov MSU PRESS, 591pp.\n http://www.pereplet.ru/lipunov/625.html#625",
  "submittedHow": "email",
  "circularId": 44023,
  "version": 3
}