Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
New! Super-Kamiokande JSON Notices and Schema v4.5.0. See news and announcements

GCN Circular 41555

Subject
EP250827a: Las Cumbres independent detection of the optical counterpart
Event
EP250827a
Date
2025-08-27T09:02:44Z (a month ago)
Edited On
2025-09-26T13:50:53Z (6 days ago)
From
Wenxiong Li at NAOC <liwenxiong1992@gmail.com>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Wenxiong Li at NAOC <liwenxiong1992@gmail.com>
Via
Web form

Wenxiong Li (NAOC), Ido Keinan (TAU), Iair Arcavi (TAU), David Sand (U of Arizona)

We observed the position of EP250827a (Hua et al. GCN 41553) with a Las Cumbres 1m telescope at CTIO starting on 2025-08-27 07:51:31 UT (less than 5 minutes after the alert and less than 11 minutes after the event). We obtained 2x300s exposures in the broad optical w band.

We find a source at RA=3.4679 Dec=-56.4979, not present in archival Legacy Survey (https://www.legacysurvey.org/viewer) images and measure a magnitude of 18.71 +- 0.06, calibrated to the r band (consistent with the Gemini detection; Levan et al. GCN 41554).

Addition followup is encouraged.
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov