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GCN Circular 9273

GRB 090423: millimeter detection
2009-04-28T00:29:21Z (15 years ago)
Alberto Castro-Tirado at Astro. de Andalucia <>
A. J. Castro-Tirado (IAA-CSIC Granada), M. Bremer and J.-M. Winters 
(IRAM Grenoble), J. Gorosabel, S. Guziy, M. Jel�nek (IAA-CSIC), P. 
Kub�nek (GACE, Univ. de Valencia), A. de Ugarte Postigo (ESO Santiago) 
and D. P�rez-Ram�rez (Univ. de Ja�n), report:

"Following the detection by Swift of GRB 090423 (Krimn et al. GCNC 
9198), millimeter observations were conducted on Apr 23 & 24 at the 
Plateau de Bure Interferometer. Consistent with the nIR afterglow 
(Tanvir et al. GCNC 9202) we clearly detect a source at 3-mm with a flux 
density of ~0.2 mJy (preliminary) on the combined dataset. Pending of 
confirming its variability we propose this as the likely millimeter 
afterglow  to GRB 090423. Considering the reported redshift values 
around z ~ 8, this is the most distant radio source detected to date.  
Further observations are scheduled. We acknowledge the Bure staff for 
its excellent support."
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