TITLE: GCN CIRCULAR NUMBER: 40022 SUBJECT: GRB 250402A: VLT/FORS2 spectroscopic redshift z = 2.823 DATE: 25/04/03 09:52:28 GMT FROM: luca.izzo@inaf.it B. Schneider (LAM), A. Saccardi (CEA/Irfu), A. de Ugarte Postigo (LAM), L. Izzo (INAF-OACn and DARK/NBI), D. B. Malesani (DAWN/NBI and Radboud), N. R. Tanvir (U. Leicester), A. Martin-Carrillo (UCD) report on behalf of the Stargate collaboration: We observed the afterglow of the SVOM/ECLAIRs GRB 250402A (Chen et al., GCN 40014; Xin et al., GCN 40015, Maggi et al., GCN 40019; Pérez-Fournon et al., GCN 40020) using the ESO/VLT UT1 (Antu) equipped with the FORS2 spectrograph. Observations started on April 3 at 05:54:45 UT (6.78 hr after the SVOM trigger). Four exposures of 600 s were obtained. From a 60 s acquisition image obtained on April 3 at 05:43:17 UT (6.59 hr after the SVOM trigger), we measure r ~ 21.1 +/- 0.2 (AB). From a preliminary reduction of the 300V spectrum, a trough due to Lya absorption is visible at 4645 AA. From the detection of multiple absorption features, which we interpret as due to Si II, O I, C II, Si IV, Si II*, C IV, Fe II, and Al II, we infer a redshift of z = 2.823. Additionally, we note the presence of an intervening absorber at z = 1.409 with multiple Fe II absorption lines. We acknowledge excellent support from the ESO observing staff in Paranal. View this GCN Circular online at https://gcn.nasa.gov/circulars/40022. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...