[vsnet-grb-info 22608] GRB 190531B: MASTER optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24707
SUBJECT: GRB 190531B: MASTER optical observation
DATE:    19/06/01 10:06:41 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E.Gorbovskoy, N.Tiurina, A.Kuznetsov, I.Gorbunov, 
V.Vladimirov, P.Balanutsa, D.Vlasenko, D.Zimnukhov, F.Balakin,A. Chasovnikov,
V.Topolev, V.Senik, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics Department),

D. Buckley (South African Astronomical Observatory),

R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA, San Juan National University),

H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE, SJNU)

R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias),

O. Gress, N.M. Budnev, O.Ershova, S.Yazev (Applied Physics Institute, Irkutsk State University),

V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University),

A. Tlatov, D.Dormidontov, A.V. Parhomenko (Kislovodsk Solar  Station of the Pulkovo Observatory),

MASTER Global Robotic Net (Lipunov et al., 2010, Advances in Astronomy,vol.2010, 30L  (http://observ.pereplet.ru)
observed Fermi GRB 190531B
(Ttrig=2019-05-31 20:10:12UT, GBM team GCN24695, Veres et al. GCN 24705;
BALROG localization RA,Dec(2000) = 27.9(+/-0.8d) -40.8(+/-0.6) Kunzweiler et al. GCN 24696, GCN 24699,
LAT localization RA,Dec= 24.37, -41.97 +-0.11d(90%)  Axelsson et al. GCN24701,
Swift XRT afterglow 01h 37m 11.09s -41d 57' 30.3"  +-1.6 arcsec(90%) D'Avanzo et al. GCN24706, Evans et al. 24702 )

At alert time
MASTER-SAAO:   Error-Box_altitude=-15d, Sun_alt=-57d.
MASTER-OAFA:   Error-Box_altitude=+15d, Sun_alt=+15d

MASTER-SAAO robotic telescope (located in South African Astronomical Observatory)
was pointed to the  GRB190531A 4934 sec after notice time and 20321 sec 
after trigger time at 2019-06-01 01:48:53 UT .
Error-box_alt=21deg, sun_alt=-47deg.
There is no OT at Swift XRT position with unfiltered mlim=20.6m

MASTER-OAFA robotic telescope (located in Argentina)
was pointed to the  GRB190531A at 2019-06-01 08:55:19UT
Error-box_alt=34deg, sun_alt=-32deg.
There is no OT at Swift XRT position with unfiltered mlim=20.0m


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