[vsnet-grb-info 22166] GRB 190427A: NOT optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24265
SUBJECT: GRB 190427A: NOT optical observations
DATE:    19/04/27 06:25:28 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani at dark-cosmology.dk>

L. Izzo (HETH/IAA-CSIC), D. B. Malesani (DAWN/NBI and DARK/NBI), D. Xu 
(NAOC/CAS), and N. Jannsen (NOT), report:

We observed the field of the Swift GRB 190427A (Tohuvavohu et al., GCN 
24261; Campana et al., GCN 24264) using the Nordic Optical Telescope 
(NOT) located in La Palma (Canary Islands, Spain), equipped with the 
ALFOSC camera. We have obtained a series of 2 exposures of 300 s each in 
the SDSS r’, i’ and z’ filters.

The first r'-band image was acquired starting on 2019 Apr 27.19742 UT 
(602 s after the GRB). Visual comparison with the Pan-STARRS archival 
images reveals no new sources inside the BAT error circle, down to a 
limiting magnitude r = 23.5 AB (calibrated against Pan-STARRS sources).

Further analysis is ongoing.