[vsnet-grb-info 25302] LIGO/Virgo S200316bj: No Counterparts in DDOTI/OAN Optical Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27402
SUBJECT: LIGO/Virgo S200316bj: No Counterparts in DDOTI/OAN Optical Observations
DATE:    20/03/17 20:43:18 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra at astro.unam.mx>

Margarita Pereyra (UNAM), Alan M. Watson (UNAM), Nat Butler (ASU), Simone
Dichiara (GSFC/UMD), Eleonora Troja (GSFC/UMD), William H. Lee (UNAM),
Alexander Kutyrev (GSFC/UMD), Rosa L. Becerra (UNAM), Diego Gonzalez
(UNAM), and Tanner Wolfram (ASU) report:

We observed LIGO/Virgo S200316bj (LIGO/Virgo Collaboration, GCN Circ.
27388) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico
Nacional on Sierra San Pedro Martir (http://ddoti.astroscu.unam.mx) on the
night of 2020-03-17 UTC.

We tiled the LVC localization with two pointings centered on 05:39:01.45
+47:47:45.23 and 05:50:02.85 +46:24:27.21 (J2000). The combined field
covers about 81 square degrees and includes about 30% of the probability in
the current BAYESTAR map.

We observed from 2020-03-17 02:44 UTC to 2020-03-17 04:27 UTC (from 4.78 to
6.5 hours after the event) obtaining exposures of 28 to 45 minutes across
the field in the w filter, with 10-sigma limiting magnitudes of w = 18.2 to
w = 18.8. We calibrate our images against the APASS catalog.

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogs we
detect no uncatalogued sources within the observed field to our 10-sigma
limit. However, we do detect the previously-cataloged transient source AT
2019dgf at w = 16.8.

We thank the staff of the Observatorio Astronomico Nacional in San Pedro
Martir.



-- 
*Dr. Margarita Pereyra *

*FFTF, Schlumberger Foundation Alumnae*
----------------------------------------------------------------------------------------------------------------

*Catedrático Conacyt*

*Instituto de Astronomía de la UNAM,*

*Km. 107 Carretera Tijua**na-Ensenada, *

*Ensenada Baja California, México. C.P. 22860*

Oficina: 405

Skype: margarita-pereyra