GCN Circular 44736
Subject
GRB 260527A/EP260527a: VLT/X-shooter tentative redshift
Event
Date
2026-05-29T10:15:04Z (10 hours ago)
From
Yu-Han Yang at University of Rome Tor Vergata <yyang@roma2.infn.it>
Via
Web form
Y.-H. Yang, E. Troja, M. El Kabir (U Rome) report on behalf of the ERC BHianca team:
We observed the field of EP260527a (Yang et al., GCN 44718), likely associated with the short GRB 260527A (Svinkin et al., GCN 44722, Yu et al., GCN 44724; Kawakubo et al., GCN 44726, Wang et al., GCN 44735) with the X-shooter spectrograph on the ESO Very Large Telescope (VLT). Observations were performed beginning at 41 hours after the GRB trigger, at an average airmass of 1.3 and in excellent conditions. Our spectra cover the wavelength range 3000-25000 AA, and consist of 4x600 s exposures.
Using a nearby bright star for blind offsets, we placed the 1 arcsec slit at the position of the optical counterpart (Aguilar-Ruiz et al., GCN 44719; Li et al., GCN 44720; Busmann et al.44728; Corcoran et al. GCN 44729, El Kabir et al. GCN 44730, O’Connor et al. GCN 44731). Based on a preliminary analysis, we report the identification of weak emission features consistent with the [OII] 3727 doublet at z ~ 0.80, which we propose as the tentative redshift of the EP transient and its underlying host galaxy.
Further observations to confirm this value are planned.
We thank the staff at the VLT for the rapid execution of these observations.