GCN Circular 43792

Subject

SVOM alert sb26021801: LCO optical upper limit

Event

sb26021801

Date

2026-02-21T14:13:23Z (3 days ago)

From

SVOM_group <svomgroup@bao.ac.cn>

Via

Web form

C. Wu (NAOC), A. Saccardi (CEA/Irfu), D. Turpin (CEA/Irfu), L.P. Xin (NAOC), and X.H. Han (NAOC) report on behalf of the SVOM mission team:

We observed the field of sb26021801 (TAN et al., GCN 43778

) with the LCO 1-m telescope, equipped with the Sinistro instrument, at both the Cerro Tololo Interamerican Observatory and the Teide Observatory (Tenerife).

Our observation started on 2026-02-18 at 06:33:39 UT (about 78.35 min after the trigger) and we obtained 3x200 s exposures in the SDSS r and 3x200 s exposures in the Pan-STARRS z filters. In the stacked image, we do not detect any new source within the SVOM/ECLAIRs error box, in agreement with Fortin et al. (GCN 43783

) and Konno et al.(GCN ).

We measure the following upper limit calibrated against the PanSTARSS DR1 catalog, and not corrected for Galactic extinction:

r > 22.1 AB (5-sigma, mid-time 83.35 min after the trigger)
z > 20.2 AB (5-sigma, mid-time 85.38 min after the trigger).

This project is funded by the SVOM collaboration.