MASTER OT J234518.89-443917.6 and MASTER OT J172202.29-645431.0 outbursts
ATel #14893; O. Gress, K. Zhirkov, P. Balanutsa, V. Lipunov, V. Kornilov, E. Gorbovskoy, Y. Kechun, T. Pogrosheva, V. Shumkov, I. Gorbunov, N. Tyurina, A. Kuznetsov, V. Vladimirov, D. Vlasenko, D. Zimnukhov, V. Senik, A. Chasovnikov, E. Minkina, V. Topolev, D. Kuvshinov, V. Grinshpun (Lomonosov Moscow State University), D. Buckley (SAAO), R. Podesta, F. Podesta, C. Lopez, C. Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), N. Budnev, O. Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory) A. Gabovich, V. Yurkov (Blagoveschensk Educational State University)
on 4 Sep 2021; 16:55 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Transient, Variables
MASTER OT J172202.29-645431.0 discovery - new OT, preliminary dwarf nova outburst with ampl>4.8m
AT2021xha
https://www.wis-tns.org/object/2021xha
MASTER-OAFA auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 17h 22m 02.29s -64d 54m 31.0s on 2021-08-31.06731 UT.
The OT unfiltered magnitude is 17.2m (mlim=18.6).
The OT is seen in 10 images. There is no minor planet at this place.
There is no any sources in VIZIER database inside 5" (22m POSS limit), it means >4.8m of current outburst amplitude (MASTER unfiltered m is calibrated for USNO-B1 as 0.2B+0.8R)
There is previous outburst of this OT in MASTER database at 2019-01-16 08:33:40UT (17.8m)
We have reference image on 2020-06-10.24444 UT with unfiltered mlim=18.9m.
http://master.sai.msu.ru/static/OT/172202.29-645431.0.png
MASTER OT J234518.89-443917.6 discovery - preliminary dwarf nova outburst with ampl>3.9
MASTER-OAFA auto-detection system
discovered OT source at (RA, Dec) = 23h 45m 18.89s -44d 39m 17.6s on 2021-09-03.22046 UT.
The OT unfiltered magnitude is 18.1m (mlim=20.2).
The OT is seen in 4 images (2021-09-03 05:14:08/06:00:45,the same magnitude). There is no minor planet at this place.
We have reference image on 2021-08-14.27042 UT with unfiltered mlimit=20.3, at 2021-08-31 07:32:23UT with mlim=19.8.
There is no sources at POSS images. There is only DES source in
VIZIER with rmag=20.98
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/234518.89-443917.6.png
Spectral observations are required.
MASTER Global Robotic Net
