EP240420a: NOT optical counterpart candidate and potential host
Abstract
We observed the field of the X-ray transient, EP 240420a, detected by EP/WXT (Zhang et al., GCN 36194) using the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera, and obtained 5 x 200 s frames in the Sloan z-band with a median time of 2024-04-21T01:01:05.287, i.e., 0.54 day after the EP trigger. The stacked z-band image has a 5-sigma limiting magnitude of z ~ 22.3. Within the 3 arcmin error circle of the EP/WXT, we identified an optical transient (OT) localized at R.A. = 15:14:55.08 (J2000) Dec. = +14:48:17.8 (J2000) with an uncertainty of radius ~ 0.3" and z ~ 21.4 mag, calibrated with the PanSTARRS field. The OT is ~ 1" south-west to a known source in the Legacy Survey (LS) which has r ~ 23.3 , z ~ 22.9, and a photometric redshift of z_phot ~ 0.82. This LS source could be the host of the OT. Further observations are encouraged.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- April 2024
- Bibcode:
- 2024GCN.36202....1A