TITLE: GCN CIRCULAR NUMBER: 10656 SUBJECT: Swift Trigger 420256: BOOTES-2 observations DATE: 10/04/23 07:16:32 GMT FROM: Javier Gorosabel at IAA-CSIC A. de Ugarte Postigo (INAF-OAB), J.Gorosabel (IAA-CSIC), A.J. Castro- Tirado (IAA-CSIC), P. Kubanek (Univ. Valencia, IAA-CSIC), M. Jelinek (IAA-CSIC) report on behalf of a larger collaboration: "We have imaged the field of Swift trigger 420256 (Hoversten et al., GCNC 10654) using the 0.6m TELMA telescope (BOOTES-2). Observations were obtained through a clear filter and began at 2:46 UT (126s after the burst). In a 1724s exposure with mid time 03:13UT (1741s after the bursts) we do not detect any new source within the BAT error box down to a 3-sigma limiting magnitude of R~18, as compared to the USNO-B1.0."