TITLE:   GCN CIRCULAR
NUMBER:  24084
SUBJECT: LIGO/Virgo S190408an: MASTER 3 OT's more detection
DATE:    19/04/09 17:17:17 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

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

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),

D. Buckley (South African Astronomical Observatory),

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

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

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

First of all, we must to say that all this OT's not connected with 
gravitational wave source, because real BBH can not produce 
detectable electromgnetic emission.

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010,Advances in Astronomy,vol. 2010, 30L)
during  LIGO/Virgo S190408an (Singer et al. GCN 24069)
inspection (Lipunov et al. GCN 24070, GCN 24076)
detected the following optical transients

1) MASTER OT J154209.55-431742.2 discovery - OT, no any sources in VIZIER, ampl>5m

MASTER-OAFA auto-detection system  Lipunov et al., "MASTER Global Robotic Net",Advances in Astronomy, 2010, 30L
  discovered OT source at (RA, Dec) = 15h 42m 09.55s -43d 17m 42.2s on 2019-04-09.06495 UT.

The OT unfiltered magnitude is 17.0m (mlim=17.9m).

The OT is seen in both 2 LVC inspect images (south part). There is no minor planet at this place.
We have reference image without OT on 2017-03-30.32611 UT with 18.6 unfiltered magnitude limit .
There is no any sources in VIZIER, it means 22m POSS limit  in history and 
more then 5m of current outburst amplitude (MASTER W=0.2B+0.8R by thousands USNO-B1 field stars)
Spectral observations are required.
The discovery and reference images are available at: 
http://master.sai.msu.ru/static/OT/154209.55-431742.2.png

2) MASTER OT J231043.63+470956.4 discovery - OT with ampl>7.1m

MASTER-Tavrida auto-detection system discovered OT source at (RA, Dec) = 23h 10m 43.63s +47d 09m 56.4s on 2019-04-09.00417 UT.
The OT unfiltered magnitude is 14.9m (limit 18.9m).
The OT is seen in 8 images. There is no sources in POSS images, it gives more then 7.1mag of current outburst amplitude.
There is PanSTARR source in 4.6", but it's too far for error of localization.

We have reference image without OT on 2019-03-18.10164 UT with unfiltered magnitude limit 18.7m.
Spectral observations are required.

The discovery and reference images are available at

http://observ.pereplet.ru/images/MASTEROTJ231043.63+470956.4.jpg

3) MASTER OT J140518.22-395309.9 discovery (Lipunov et al. GCN24076) also detected by ATLAS (Smart et al. GCN 24078) in March


MASTER cover map of Ligo/Virgo S190408an error-field inspection  will be
available on-line at:

http://master.sai.msu.ru/static/LVC/MASTER_S190408an_map.jpg

  Reduction and observation will be cntinued.

The message may be cited.