GCN Circular 33895

V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez 
(INAOE, Guillermo Haro Astrophysics Observatory),

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

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


MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the LIGO/Virgo S230529ay errorbox  35464 sec after notice time and 35512 sec after trigger time at 2023-05-30 04:06:52 UT, with upper limit up to  20.0 mag. The observations began at zenith distance = 44 deg. The sun  altitude  is -79.1 deg. 

The galactic latitude b = 10 deg., longitude l = 351 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/ligo_1.php?id=11912

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

   35602 | 2023-05-30 04:06:52 |         MASTER-OAFA | (19h 30m 28.49s , -54d 33m 15.6s) |   C |   180 | 17.5 |        
   35782 | 2023-05-30 04:06:52 |         MASTER-OAFA | (19h 30m 28.48s , -54d 33m 15.6s) |   C |   540 | 17.7 |  Coadd 
   35802 | 2023-05-30 04:10:11 |         MASTER-OAFA | (19h 44m 00.85s , -54d 34m 42.6s) |   C |   180 | 17.3 |        
   35982 | 2023-05-30 04:10:11 |         MASTER-OAFA | (19h 44m 00.85s , -54d 34m 42.7s) |   C |   540 | 17.1 |  Coadd 
   36001 | 2023-05-30 04:13:31 |         MASTER-OAFA | (19h 01m 09.49s , -56d 46m 37.5s) |   C |   180 | 16.5 |        
   36201 | 2023-05-30 04:16:50 |         MASTER-OAFA | (19h 15m 33.95s , -56d 48m 33.1s) |   C |   180 | 16.7 |        
   36400 | 2023-05-30 04:20:10 |         MASTER-OAFA | (19h 30m 28.92s , -54d 32m 13.8s) |   C |   180 | 17.1 |        
   36605 | 2023-05-30 04:23:34 |         MASTER-OAFA | (19h 44m 00.34s , -54d 33m 38.6s) |   C |   180 | 16.1 |        
   36804 | 2023-05-30 04:26:54 |         MASTER-OAFA | (19h 01m 08.06s , -56d 46m 09.6s) |   C |   180 | 16.1 |        
   37004 | 2023-05-30 04:30:13 |         MASTER-OAFA | (19h 15m 38.21s , -56d 47m 39.9s) |   C |   180 | 15.3 |        
   37203 | 2023-05-30 04:33:33 |         MASTER-OAFA | (19h 30m 23.62s , -54d 34m 09.8s) |   C |   180 | 16.6 |        
   37404 | 2023-05-30 04:36:54 |         MASTER-OAFA | (19h 44m 06.81s , -54d 34m 15.8s) |   C |   180 | 14.3 |        
   38403 | 2023-05-30 04:53:33 |         MASTER-OAFA | (19h 01m 07.43s , -56d 48m 08.9s) |   C |   180 | 12.2 |        
   38583 | 2023-05-30 04:53:33 |         MASTER-OAFA | (19h 01m 07.47s , -56d 48m 09.0s) |   C |   540 | 17.0 |  Coadd 
   38603 | 2023-05-30 04:56:52 |         MASTER-OAFA | (19h 15m 38.31s , -56d 48m 36.1s) |   C |   180 | 13.6 |        
   38802 | 2023-05-30 05:00:12 |         MASTER-OAFA | (19h 30m 28.11s , -54d 32m 28.0s) |   C |   180 | 15.6 |        
   38982 | 2023-05-30 05:00:12 |         MASTER-OAFA | (19h 30m 28.13s , -54d 32m 28.0s) |   C |   540 | 17.4 |  Coadd 
   39002 | 2023-05-30 05:03:31 |         MASTER-OAFA | (19h 44m 05.53s , -54d 34m 27.1s) |   C |   180 | 16.8 |        
   39201 | 2023-05-30 05:06:51 |         MASTER-OAFA | (19h 01m 14.67s , -56d 46m 26.1s) |   C |   180 | 16.9 |        
   39600 | 2023-05-30 05:13:30 |         MASTER-OAFA | (19h 30m 26.22s , -54d 32m 07.7s) |   C |   180 | 17.4 |        
   39800 | 2023-05-30 05:16:49 |         MASTER-OAFA | (19h 44m 09.80s , -54d 33m 33.8s) |   C |   180 | 18.4 |        
   40000 | 2023-05-30 05:20:09 |         MASTER-OAFA | (19h 01m 09.23s , -56d 48m 12.2s) |   C |   180 | 17.0 |        
   40199 | 2023-05-30 05:23:28 |         MASTER-OAFA | (19h 15m 39.38s , -56d 48m 21.4s) |   C |   180 | 17.5 |        
   40379 | 2023-05-30 05:23:28 |         MASTER-OAFA | (19h 15m 39.38s , -56d 48m 21.3s) |   C |   540 | 18.0 |  Coadd 
   40439 | 2023-05-30 05:27:29 |         MASTER-OAFA | (19h 30m 29.31s , -54d 34m 02.2s) |   C |   180 | 17.3 |        
   40459 | 2023-05-30 05:27:48 |         MASTER-OAFA | (19h 01m 10.37s , -56d 46m 13.3s) |   C |   180 | 17.9 |        
   40658 | 2023-05-30 05:31:08 |         MASTER-OAFA | (19h 15m 40.91s , -56d 47m 41.2s) |   C |   180 | 18.0 |        
   40858 | 2023-05-30 05:34:27 |         MASTER-OAFA | (18h 44m 35.92s , -54d 32m 44.0s) |   C |   180 | 18.4 |        
   41107 | 2023-05-30 05:38:37 |         MASTER-OAFA | (18h 58m 10.02s , -54d 31m 38.1s) |   C |   180 | 17.6 |        
   41127 | 2023-05-30 05:38:56 |         MASTER-OAFA | (19h 44m 10.12s , -54d 32m 51.9s) |   C |   180 | 17.1 |        
   41347 | 2023-05-30 05:42:36 |         MASTER-OAFA | (19h 01m 10.04s , -56d 47m 16.0s) |   C |   180 | 17.4 |        
   41566 | 2023-05-30 05:46:16 |         MASTER-OAFA | (19h 15m 36.26s , -56d 46m 41.8s) |   C |   180 | 15.8 |        
   41869 | 2023-05-30 05:51:19 |         MASTER-OAFA | (18h 44m 30.25s , -54d 30m 46.4s) |   C |   180 | 16.1 |        
   42049 | 2023-05-30 05:51:19 |         MASTER-OAFA | (18h 44m 30.24s , -54d 30m 46.4s) |   C |   540 | 18.3 |  Coadd 
   42124 | 2023-05-30 05:55:34 |         MASTER-OAFA | (18h 58m 06.98s , -54d 31m 10.7s) |   C |   180 | 17.7 |        
   42304 | 2023-05-30 05:55:34 |         MASTER-OAFA | (18h 58m 06.96s , -54d 31m 10.7s) |   C |   540 | 19.0 |  Coadd 
   42344 | 2023-05-30 05:59:13 |         MASTER-OAFA | (19h 30m 33.38s , -54d 33m 08.8s) |   C |   180 | 16.5 |        
   42564 | 2023-05-30 06:02:54 |         MASTER-OAFA | (19h 44m 05.20s , -54d 34m 32.2s) |   C |   180 | 17.8 |        
   42955 | 2023-05-30 06:09:24 |         MASTER-OAFA | (19h 01m 18.55s , -56d 48m 07.4s) |   C |   180 | 16.9 |        
   43020 | 2023-05-30 06:10:30 |         MASTER-OAFA | (18h 44m 35.08s , -54d 32m 23.2s) |   C |   180 | 17.5 |        
   43239 | 2023-05-30 06:14:09 |         MASTER-OAFA | (18h 58m 14.61s , -54d 31m 13.0s) |   C |   180 | 18.6 |        
   43459 | 2023-05-30 06:17:48 |         MASTER-OAFA | (18h 44m 33.23s , -54d 30m 50.7s) |   C |   180 | 18.6 |        
   43678 | 2023-05-30 06:21:28 |         MASTER-OAFA | (18h 58m 15.00s , -54d 32m 15.5s) |   C |   180 | 18.7 |        
   43944 | 2023-05-30 06:25:54 |         MASTER-OAFA | (18h 44m 39.81s , -54d 31m 52.1s) |   C |   180 | 18.7 |        
   44124 | 2023-05-30 06:25:54 |         MASTER-OAFA | (18h 44m 39.81s , -54d 31m 52.1s) |   C |   540 | 19.3 |  Coadd 
   44164 | 2023-05-30 06:29:33 |         MASTER-OAFA | (18h 58m 10.72s , -54d 33m 09.7s) |   C |   180 | 18.7 |        
   44344 | 2023-05-30 06:29:33 |         MASTER-OAFA | (18h 58m 10.72s , -54d 33m 09.7s) |   C |   540 | 19.4 |  Coadd 
   44383 | 2023-05-30 06:33:13 |         MASTER-OAFA | (18h 44m 39.91s , -54d 32m 09.9s) |   C |   180 | 18.8 |        
   44603 | 2023-05-30 06:36:52 |         MASTER-OAFA | (18h 58m 14.62s , -54d 31m 16.5s) |   C |   180 | 18.8 |        
   44822 | 2023-05-30 06:40:31 |         MASTER-OAFA | (18h 44m 38.06s , -54d 32m 26.4s) |   C |   180 | 18.8 |        
   45087 | 2023-05-30 06:44:56 |         MASTER-OAFA | (18h 58m 11.48s , -54d 30m 50.1s) |   C |   180 | 18.8 |        
   45306 | 2023-05-30 06:48:36 |         MASTER-OAFA | (18h 44m 41.94s , -54d 31m 29.9s) |   C |   180 | 18.9 |        
   45526 | 2023-05-30 06:52:15 |         MASTER-OAFA | (18h 58m 12.89s , -54d 32m 53.1s) |   C |   180 | 18.9 |        
   45745 | 2023-05-30 06:55:55 |         MASTER-OAFA | (18h 44m 43.01s , -54d 32m 04.3s) |   C |   180 | 18.9 |        
   45965 | 2023-05-30 06:59:35 |         MASTER-OAFA | (18h 58m 16.26s , -54d 31m 06.3s) |   C |   180 | 18.9 |        
   46185 | 2023-05-30 07:03:14 |         MASTER-OAFA | (21h 07m 49.25s , -43d 19m 29.1s) |   C |   180 | 19.0 |        
   46365 | 2023-05-30 07:03:14 |         MASTER-OAFA | (21h 07m 49.24s , -43d 19m 29.1s) |   C |   540 | 19.7 |  Coadd 
   46412 | 2023-05-30 07:07:01 |         MASTER-OAFA | (21h 18m 37.52s , -43d 20m 22.6s) |   C |   180 | 19.1 |        
   46592 | 2023-05-30 07:07:01 |         MASTER-OAFA | (21h 18m 37.52s , -43d 20m 22.6s) |   C |   540 | 19.8 |  Coadd 
   46632 | 2023-05-30 07:10:41 |         MASTER-OAFA | (21h 05m 33.17s , -47d 50m 06.3s) |   C |   180 | 19.2 |        
   46812 | 2023-05-30 07:10:41 |         MASTER-OAFA | (21h 05m 33.17s , -47d 50m 06.3s) |   C |   540 | 19.9 |  Coadd 
   46851 | 2023-05-30 07:14:21 |         MASTER-OAFA | (21h 17m 14.87s , -47d 51m 22.5s) |   C |   180 | 19.1 |        
   47031 | 2023-05-30 07:14:21 |         MASTER-OAFA | (21h 17m 14.88s , -47d 51m 22.5s) |   C |   540 | 19.9 |  Coadd 
   47071 | 2023-05-30 07:18:01 |         MASTER-OAFA | (21h 07m 49.44s , -43d 20m 57.2s) |   C |   180 | 19.2 |        
   47291 | 2023-05-30 07:21:40 |         MASTER-OAFA | (21h 18m 41.65s , -43d 19m 49.5s) |   C |   180 | 19.1 |        
   47510 | 2023-05-30 07:25:20 |         MASTER-OAFA | (21h 05m 30.21s , -47d 50m 58.9s) |   C |   180 | 19.2 |        
   47730 | 2023-05-30 07:29:00 |         MASTER-OAFA | (21h 17m 21.25s , -47d 49m 32.0s) |   C |   180 | 19.1 |        
   47955 | 2023-05-30 07:32:44 |         MASTER-OAFA | (21h 07m 44.55s , -43d 20m 09.8s) |   C |   180 | 19.3 |        
   48178 | 2023-05-30 07:36:28 |         MASTER-OAFA | (21h 18m 38.89s , -43d 19m 23.4s) |   C |   180 | 19.1 |        
   48382 | 2023-05-30 07:39:51 |         MASTER-OAFA | (21h 05m 34.34s , -47d 50m 09.6s) |   C |   180 | 19.2 |        
   48581 | 2023-05-30 07:43:11 |         MASTER-OAFA | (21h 17m 15.72s , -47d 51m 25.2s) |   C |   180 | 19.2 |        
   48810 | 2023-05-30 07:47:00 |         MASTER-OAFA | (21h 07m 47.95s , -43d 19m 33.3s) |   C |   180 | 19.3 |        
   48990 | 2023-05-30 07:47:00 |         MASTER-OAFA | (21h 07m 47.95s , -43d 19m 33.3s) |   C |   540 | 20.0 |  Coadd 
   49030 | 2023-05-30 07:50:39 |         MASTER-OAFA | (21h 18m 42.68s , -43d 21m 22.8s) |   C |   180 | 19.2 |        
   49210 | 2023-05-30 07:50:39 |         MASTER-OAFA | (21h 18m 42.68s , -43d 21m 22.9s) |   C |   540 | 19.9 |  Coadd 
   49249 | 2023-05-30 07:54:19 |         MASTER-OAFA | (21h 05m 27.48s , -47d 50m 12.3s) |   C |   180 | 19.2 |        
   49456 | 2023-05-30 07:57:45 |         MASTER-OAFA | (21h 17m 16.41s , -47d 49m 26.9s) |   C |   180 | 19.3 |        
   49655 | 2023-05-30 08:01:05 |         MASTER-OAFA | (21h 07m 51.38s , -43d 20m 14.2s) |   C |   180 | 19.3 |        
   49855 | 2023-05-30 08:04:24 |         MASTER-OAFA | (21h 18m 40.24s , -43d 21m 27.2s) |   C |   180 | 19.2 |        
   50054 | 2023-05-30 08:07:44 |         MASTER-OAFA | (21h 05m 34.85s , -47d 51m 06.0s) |   C |   180 | 19.1 |        
   50254 | 2023-05-30 08:11:03 |         MASTER-OAFA | (21h 17m 20.16s , -47d 49m 32.0s) |   C |   180 | 18.3 |        
   50473 | 2023-05-30 08:14:43 |         MASTER-OAFA | (21h 07m 48.91s , -43d 21m 05.2s) |   C |   180 | 19.2 |        
   50693 | 2023-05-30 08:18:22 |         MASTER-OAFA | (21h 18m 46.84s , -43d 19m 37.9s) |   C |   180 | 19.1 |        
   50919 | 2023-05-30 08:22:09 |         MASTER-OAFA | (17h 58m 36.70s , -30d 31m 04.3s) |   C |   180 | 16.2 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.