GCN Circular 25573

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

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

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


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),



MASTER-Amur robotic telescope (Global MASTER-Net: 
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical 
University) was pointed to the  GRB190829A (Fermi GCN 25551
Not found
 
 
 )  55 sec 
after Swift trigger  time (Dichiara et al., GCN 25552
Not found
 
 
) at  2019-08-29 19:57:39   UT. The 
5-sigma image limit has been about 14.5 mag


MASTER-Kislovodsk robotic telescope was pointed to the  GRB190829A  by 
FERMI GBM coordinates  15 s after trigger time at 2019-08-29 19:56:59 in 
two polarizations.
The Swift BAT position was 2 degree below horison at this time on 
MASTER-Kislovodsk in two polarizations.  The first image at Swift BAT 
position was obtained 909 s after trigger at 2019-08-29 20:11:53, but due to extrimelly high zenith 
distance (89.5 degree) this images has no stars. The first images with 
stars  was obtained  1239 s after trigger at 2019-08-29 20:17:23 (zenith 
distance 88.7).

The both FERMI-GBM and Swift BAT position was below horisont at 
MASTER-SAAO,  MASTER-Tavrida and MASTER-OAFA sites. Thus, automatic 
pointing was not possible.

MASTER-SAAO robotic telescope  located in South Africa (South African 
Astronomical Observatory) was pointed to the GRB190829A errorbox  6757 sec 
after trigger time at 2019-08-29 21:49:21 UT, with upper limit up to  21.3 
mag. The observations began at zenit distance = 76 deg. The sun  altitude 
is -64.5 deg.

MASTER-Tavrida robotic telescope  located in Russia (Lomonosov MSU, SAI 
Crimea astronomical station) was pointed to the  GRB190829.83 errorbox 
6766 sec after trigger time at 2019-08-29 21:49:30 UT, with upper limit up 
to  18.5 mag. The observations began at zenit distance = 79 deg. The sun 
altitude  is -36.7 deg.

MASTER-OAFA robotic telescope  located in Argentina (OAFA observatory of 
San Juan National University) joined  to the  GRB190829A observations 
27862 sec after trigger time at 2019-08-30 03:41:06 UT, with upper limit 
up to  19.8 mag. The observations began at zenit distance = 77 deg. The 
sun  altitude  is -64.8 deg.
Observation with the MASTER-OAFA telescope continues.


Swift team  noted   the presence of a galaxy SDSS J025810.28-085719.2 
(PGC997094) with z=0.07914 centered at a distance of 10 arcseconds from 
the XRT location.

The aftergrlow was detected indipendingly by ( Xu et al. GCNC 25555,
Lipunov et al. GCNC 25558).
We see object with 3.1E	7.5S arcsec ofsset from the galaxy center.


Optical afterglow spectrum displays a red 
continuum  (Valeev et al., 25565) consistent with the
NOT results (Heintz et al. GCNC 25563) at redshift z = 0.0785 +/- 0.005 
which coincided with PGC Galaxy.

Very late brightening (up to 1 hour after trigger)  in our data, says 
about the unusual nature of this phenomenon. By the way, after 
the maximum of the brightness of the brightness decreases linearly with 
time!

Obviously, this fact indicates the affinity of the galaxy and the 
gamma-evant.

If a very probable connection between the gamma-ray burst and the nearby 
galaxy PGC997094 at a distance of ~ 320 Megaparsec  and the lack of
an LVC alert can make an  important conclusion (VML):
as expected, the collapse of the progenitor core proceeds through the slow 
(on the scale of the radial fall time) compression of the quasicylindrical 
object - the spinar (Lipunov & Gorbovskoy, 2007, ApJ, vol. 665, 
97; Lipunov & Gorbovskoy, MNRAS, 2008, vol. 383, 1397;
Lipunova et al., MNARS, 2009, vol. 397; 1695 .

The one of the automatic detection images is available at
master.sai.msu.ru/static/OT/GRB190829.jpg

You can see the tools of the MASTER robot in Kislovodsk. From left to 
right: the image corresponds to the specified time, the next frame of the 
DSS,  the next is difference between the new and the reference frame, 
frame from  SDSS.

Below are two frames of today's observation. Then a logarithm frame. 
Finaly, old reference frame.

Ruduction is continue.
This message can be cited.