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GCN Circular 995

GRB 010222
2001-02-27T12:56:58Z (23 years ago)
Michael Bremer at IRAM Grenoble <>
Interferometric Millimeter Observations of GRB 010222

M. Bremer (1), A. Castro-Tirado (2,3) and R. Moreno(1) report:
  (1) IRAM    (Grenoble, France)
  (2) IAA-CSIC  (Granada, Spain)
  (3) LAEFF-INTA (Madrid, Spain)

We have observed the GRB 010222 radio counterpart with the Plateau 
de Bure Interferometer (PdBI) in a compact five antenna configuration
on February 24.94 - 25.11 UT, using the position from Henden et al. 
(GCN 967).  Weather conditions were good for wavelengths of 3mm but 
marginal for 1mm.  The flux calibration was relative to CRL 618 
(1.55 Jy at 3mm and 2 Jy at 1mm) and is accurate to about 10%.

The source was not detected.  UV fits on the phase center give the 
following upper limits (fit errors are one sigma) :

  93.109 GHz : -0.49 +- 0.32 mJy/beam  
 232.032 GHz : -0.09 +- 1.6  mJy/beam

The results have been corrected for atmospheric decorrelation.
Synthesized beams were 9.3" x 5.2" at PA -57 degrees and 3.6" by 2.3" 
at PA -46 degrees, respectively.  No bright sources were detected 
within the primary beam.
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