GCN Circular 24326
Subject
LIGO/Virgo S190425z: MASTER explanation of the nature of an optical flash detected by a Swift as a short flare on a fast-moving WISE brown
Date
2019-04-28T11:05:43Z (5 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, N.Tyurina, E. Gorbovskoy, V.Kornilov, D.Vlasenko,
V.Vladimirov, D.Zimnukhov, A.Kuznetsov, P.Balanutsa, I.Gorbunov, A.
Chasovnikov, V.Grinshpun, F.Balakin, A.Chasovnikov
(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),
Global MASTER-Net (http://observ.pereplet.ru, Lipunov et al., 2010,
Advances in Astronomy, vol. 2010, 30L) started inspect of the
LIGO/Virgo S190425z errorbox (Singer et al. GCN 24168) 3133 sec after
trigger time at 2019-04-25 09:10:18 UT (Lipunov et al. GCN 24167).
MASTER-IAC observed Swift OT (Breeveld et al., GCN 24296) at 2019-04-26
01:45:59 with mlim=20.0, and at 2019-04-26 01:57:23 with mlim=20.0
during automatic inspect of GW190425.
There is optical transient with m_OT ~ 19.0 detected at both
images.
MASTER-OAFA observed these coordinates at 2019-04-26 05:24:35 during
automatic GW190425 inspection with unfiltered mlim=19.0. There is no OT
detection.
MASTER-SAAO observed this area at 2019-04-27 21:15:24 and at 2019-04-27
21:26:02 with mlim=21.0 and at 2019-04-26 04:01:55 with mlim=19.3 during
automatic GW190425 inspection . There is no OT detection.
All instrumental unfiltered magnitude is W = 0.2B + 0.8R with respect to
USNO B reference stars.
The object detected by Swift possibly connected with the blue flare on
fast moving cool AllWISE star (RA,DEC) = 255.5777822 -12.4869992 (2" per
yr!).
So this OT not connected with Gravitational Waves Event.
You can find below the community observations of the Swift OT
region:
Telescope Apr Limit OT Filt GCN
Zwicky 25.4 20.5 - R 24302
Zwicky 25.4 20.5 - g 24302
ASAS-SN 25.4 18.7 - g 24313
Gattini 25.5 15.2 - J 24306
Zwicky 25.5 20.5 - R 24302
KMTNet SSO 25.6 21.5 - R 24318
MASTER-IAC 26.1 20.0 19.0 W This
MASTER-OAFA 26.2 19.0 19.0 W This
Zwicky 26.3 20.5 - g 24302
Gattini 26.4 15.2 - J 24306
Zwicky 26.5 20.4 - R 24302
ASAS-SN 26.5 18.7 - g 24313
Swift 26.8 ? 17.7 U 24296
ASAS-SN 27.3 18.4 - g 24313
MASTER-SAAO 27.88 21.0 - W This
LCO SAAO 27.9 21.5 - R 24307
Lulin 28.8 21.5 - R 24301
These data do not contradict the hypothesis of a short (10-15 minutes
flash) on a red-brown dwarf.
The message may be cited.