[AAVSO-HEN] GRB051227: further analysis of VLT images

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4413
SUBJECT: GRB051227: further analysis of VLT images
DATE:    05/12/29 18:30:10 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <davanzo at merate.mi.astro.it>

P. D'Avanzo, S. Covino (INAF/OABr), D. Malesani (SISSA), S. Piranomonte,
L.A. Antonelli (INAF/OAR), S. Campana (INAF/OABr), report on behalf of
the MISTICI collaboration:

We further analyzed our VLT images (Malesani et al., GCN 4404, 4412) of
GRB 051227 (Barbier et al., GCN 4397; Hullinger et al., GCN 4400;
Barthelmy et al., GCN 4401). Optimal subtraction performed with the ISIS
package on our two set of images (taken on Dec 28.2 and 29.2 UT) clearly
shows a dimming of the source S1 (Malesani et al., GCN 4404). A figure
showing the result of the subtraction can be found at the following URL:

  http://www.sissa.it/~malesani/GRB/051227/subtraction.jpg

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