TITLE:   GCN CIRCULAR
NUMBER:  9100
SUBJECT: GRB 090404: millimeter detection
DATE:    09/04/06 22:15:32 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, P. Kubánek
(IAA-CSIC), A. de Ugarte Postigo (ESO Santiago) and D. Pérez-Ramírez
(Univ. de Jaén), report:

"Following the detection by Swift of GRB 090404 (Ziaeepour et al. GCNC
9086), millimeter observations were conducted on Apr 5.9 UT at the Plateau
de Bure Interferometer. Consistent the Swift/XRT enhanced position
(Beardmore et al. GCNC 9088) we clearly detect a millimeter source with a
108 GHz flux density of 1.1 mJy at coordinates RA(2000) = 15:56:57.52,
Dec(2000) = +35:30:57.5 with (0.3",0.2") 1-sigma error in (RA,DEC).
Pending of confirming its variability we propose this as the likely
millimeter afterglow to GRB 090404. Together with the lack of optical and
near-IR afterglows (Xin et al. GCNC 9090, Yock et al. GCNC 9092, Malesani
et al. GCNC 9095, Afonso et al. GCNC 9096, Jelínek et al. GCNC 9099), this
event strongly resembles the dark burst GRB 051022 (Castro-Tirado et al.
2007, A&A 475, 101). Further millimeter observations are scheduled."

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