GRB 241209A
GCN Circular 38608
Subject
GRB 241209A: ATCA radio follow-up observations
Date
2024-12-18T07:11:43Z (a year ago)
From
Tao An at SHAO, CAS <antao@shao.ac.cn>
Via
Web form
Tao An, Yuanqi Liu (SHAO), Jinjun Geng (PMO), and Xuefeng Wu (PMO) report on behalf of the Einstein Probe radio follow-up team:
Following the detection of GRB 241209A by Fermi and Swift (Hamburg et al. 2024, GCN 38502; Evans et al. 2024, GCN 38523), we conducted radio follow-up observations using the Australia Telescope Compact Array (ATCA). We observed the VLT position [RA(J2000) = 10:21:35.14, Dec(J2000) = +06:19:44.5] during UTC 16:00:00-22:00:00 on December 14, 2024. No significant emission was detected at either 5.5 GHz or 9 GHz, yielding 3σ upper limits of 51 microJy and 36 microJy, respectively.
We thank the ATCA team for their rapid scheduling and support.
GCN Circular 38538
Subject
GRB 241209A: Chandra X-ray Detection
Date
2024-12-11T19:27:31Z (a year ago)
From
Peter Blanchard at Harvard <peter.blanchard@cfa.harvard.edu>
Via
Web form
Peter K. Blanchard and Edo Berger (Harvard) report on behalf of a larger collaboration:
We observed the short GRB 241209A (GCNs 38474, 38476) with Chandra/ACIS (Program 25500091, PI: Berger) starting at UT 2024-12-10 13:47:26 with an exposure time of 19.8 ks (mid-time of 38.4 hr post-burst). We detect a source consistent with the enhanced Swift/XRT position (GCN 38486) at the following coordinates:
RA (J2000): 10:21:35.207
Dec (J2000): +06:19:42.73
with a one sigma uncertainty of 0.3” in RA and Dec.
The X-ray source is closer (~0.6” away) to the fainter galaxy of the two identified by de Ugarte Postigo et al. (GCN 38484), which has a redshift of z=1.490 (GCN 38487). The source is ~2” away from the infrared source identified by Schneider et al. (GCN 38506).
We thank the Chandra team for rapidly scheduling these observations.
GCN Circular 38535
Subject
GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
Date
2024-12-11T13:22:54Z (a year ago)
From
Antonio de Ugarte Postigo at LAM/OCA, CNRS <deugarte@oca.eu>
Via
email
A. de Ugarte Postigo (OCA and LAM, CNRS), D. B. Malesani (DAWN/NBI and Radboud Univ.), J. F. Agui Fernandez (CAHA), N. R. Tanvir (U. Leicester), C. C. Thoene (ASU-CAS, AbAO), N. A. Rakotondrainibe (LAM), L. Izzo (INAF-OACn & DARK/NBI), A. Martin-Carrillo (UCD), J. P. U. Fynbo (DAWN/NBI), S. Geier (GTC), G. L. Lombardi (GTC), N. Castro Rodriguez (GTC), A. Marante-Barreto (GTC), A. Cabrera Lavers (GTC) report:
The refined X-ray counterpart error region (Evans et al., GCN 38486) of the short GRB 241209A (Fermi collaboration, GCN 38474