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GCN Circular 34731

AT 2023sva: NOT observations of the ZTF candidate afterglow
2023-09-18T21:29:35Z (10 months ago)
Daniele B. Malesani at IMAPP / Radboud University <>
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D. B. Malesani (Radboud Univ. and DAWN/NBI) and Maria B. Stone (Turku Univ.) report on behalf of a larger collaboration:

We observed the transient AT 2023sva (Vail et al., GCN 34730; Tonry et al. 2023, TNS report 188327), a candidate afterglow of the Fermi-GBM trigger 716527670 from 2023 September 16, using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera.

Observations started on 2023 Sep 18.84 (2.70 days after the GBM trigger), in twilight, at a large airmass, and consisted in a single 300-s exposure in each of the SDSS r and g filters.

In our image, the transient is clearly detected with a magnitude r = 20.7 +- 0.1 AB, calibrated against nearby stars from the Pan-STARRS catalog.
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