TITLE:   GCN CIRCULAR
NUMBER:  9273
SUBJECT: GRB 090423: millimeter detection
DATE:    09/04/28 00:29:21 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

A. J. Castro-Tirado (IAA-CSIC Granada), M. Bremer and J.-M. Winters 
(IRAM Grenoble), J. Gorosabel, S. Guziy, M. Jelínek (IAA-CSIC), P. 
Kubánek (GACE, Univ. de Valencia), A. de Ugarte Postigo (ESO Santiago) 
and D. Pérez-Ramírez (Univ. de Jaén), 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."