Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 24455

LIGO/Virgo S190510g: GRAWITA REM optical observations
2019-05-10T14:42:46Z (5 years ago)
Maria Grazia Bernardini at INAF/Brera <>
P. D'Avanzo (INAF-OAB), L. Izzo (IAA), S. Yang (INAF-OAPd), E. Palazzi 
(INAF-OAS), S Campana (INAF-OAB),

S. Benetti (INAF-OAPd), M.G. Bernardini (INAF-OAB), M.T. Botticella 
(INAF-OAC), M. Branchesi (GSSI),

A. Bulgarelli (INAF-OAS), S. Campana (INAF-OAB), E. Cappellaro 
(INAF-OAPd), R. Carini (INAF-OAR), R. Ciolfi (INAF-OAPd),

S. Covino (INAF-OAB), V. D'Elia (ASI-SSDC), M. Della Valle (INAF-OAC), 
 �A. Grado (INAF-OAC), G. Greco (Univ. Urbino),

A. Melandri (INAF-OAB), L. Nicastro (INAF-OAS), S. Piranomonte 
(INAF-OAR), A. Rossi (INAF-OAS), V. Testa (INAF-OAR),

L. Tomasella (INAF-OAPd), E. Brocato (INAF-OAAb, INAF-OAR), on behalf of 
GRAWITA report:

We carried out optical follow-up observations of the LIGO/Virgo GW 
trigger S190509g (LVC, GCN Circ. 24442) with the 60-cm

robotic telescope REM located at the La Silla Observatory (Chile). The 
observations started at 2019-05-10 at 05:27:51 UT,

simultaneously in the g, r, i, z bands (the REM NIR camera was not 

We observed the following galaxies within the 90% probability of the 
initial bayestar skymap visible from La Silla:

RA(J2000) Dec(J2000) Dist(Mpc) Abs_Mag(B)


 �14:40:29.9303:14:01.1 ��400.91 -20.19

 �13:40:22.5600:14:12.1 ��335.74 -19.36

 �13:39:26.41-04:38:43.7 ��331.50 -20.14

 �14:40:56.6403:09:10.7 ��376.70 -19.83

 �14:17:12.5701:59:31.5 ��261.43 -20.30

 �13:17:09.12-00:57:28.1 ��366.44 -19.74

 �13:40:11.16-04:36:24.0 ��351.69 -19.99

 �14:55:34.8008:39:43.5 ��376.70 -19.51

 �14:32:03.12-01:10:03.7 ��243.01 -19.33

 �14:31:11.16-02:37:20.2 ��315.22 -19.81

 �14:29:11.5209:38:11.6 ��385.48 -18.77

 �14:17:44.1601:58:52.6 ��259.42 -20.12

 �14:30:39.4007:16:30.0 ���21.40 -19.47

 �14:44:57.6000:50:40.1 ��317.69 -18.18

 �13:53:50.6400:50:43.3 ��279.25 -19.74

No clear counterpart for S190509g is found down to a typical 3sigma 
magnitude of r > 19 (AB).

We report the presence of a possible transient (likely unrelated to 
S190509g) found in the analysis of the REM

frames at the following coordinates (J2000):

RA = 14:29:15.99

Dec = +09:41:12.3

(+/- 1").

The source has a magnitude of r = 17.3 +/- 0.1 (AB, calibrated against 
the SDSS). We note that this object is

3.5" from the SDSS galaxy SDSS J142916.22+094112.1, whose catalogue 
magnitude is r = 22.56 +/- 0.20 and

photometric redshift is z = 0.182 +/- 0.073.

Further analysis and observations are planned.
Looking for U.S. government information and services? Visit