TITLE:   GCN CIRCULAR
NUMBER:  39341
SUBJECT: EP250215a / GRB 250215A : NOT optical observations 
DATE:    25/02/16 03:06:15 GMT
FROM:    Daniele B. Malesani at IMAPP / Radboud University <d.malesani@astro.ru.nl>

D. B. Malesani (DAWN/NBI and Radboud Univ), D. Xu (NAOC), N. Pyykkinen (NOT and Turku Univ.), M. A. Diaz Teodori (NOT and Turku Univ.) report on behalf of a larger collaboration:

We observed the optical counterpart (Liu et al., GCN 39330; Xie et al., GCN 39333; Malesani et al., GCN 39339) of EP250215a / GRB 250215A (Wang et al., GCN 39329; Fermi GBM Team, GCN 39327; Barria et al., GCN 39331; Tembhurnikar et al., GCN 39334; Zheng et al., GCN 39335) using the ALFOSC instrument installed on the Nordic Optical Telescope (NOT). Observations were carried out in the i band and consisted of 5x300 s exposures, with a mean epoch 2025 Feb 16.076 UT (23.29 hr after the trigger).

The afterglow is well detected with a magnitude i = 21.34 +- 0.07 AB, calibrated against several stars from the Pan-STARRS catalog.