{
  "bibcode": "2021GCN.31070....1M",
  "body": "Daniele B. Malesani (Radboud Univ. and DAWN/NBI), Paolo D'Avanzo \n(INAF/OABr), Andrew J. Levan (Radboud Univ.), Ana Nicuesa Guelbenzu (TLS \nTautenburg), report on behalf of the Stargate consortium:\n\n\nWe observed the location of XRT source #2 (D'Elia et al., GCNs 31051, \n31068), indicated as the X-ray afterglow of the short GRB 211106A \n(Tohuvavohu et al., GCN 31049; Ridnaia et al., GCN 31054; Fletcher, GCN \n31055) using the ESO VLT UT1 equipped with the FORS2 camera. A total of \n20 minutes on source were obtained in the R band, with mid time 2021 Nov \n9.116 UT (that is, 2.92 days after the GRB).\n\nNo bright sources are detected inside the XRT error circle, down to R > \n26.2 (Vega, preliminary calibration based on faint USNO-B1 stars). \nHowever, there are two extended (FWHM ~ 2\") objects at the following \ncoordinates:\n\nRA = 22:54:21.31\nDec = -53:13:47.2\n\nRA = 22:54:20.29\nDec = -53:13:53.6\n\nThe second one is partially blended with a brighter star. These two \ngalaxies are 7.9\" and 4.8\" away, respectively, from the center of the \nXRT position (which has currently a 90% uncertainty radius of 3.4\"). A \nfaint extension of the most nearby object, or a separate, very faint \nsource, is also marginally detected inside the XRT error circle.\n\n\nShould the GRB be associated with one of the closeby galaxies, this \nwould indicate a relatively low redshift. Lacking a reference image, we \ncannot yet ascertain whether a faint transient could be present, \nsuperposed on top of the galaxy light. Chandra X-ray observations would \nhelp pinpoint the precise location of the source.\n\n\nWe acknowledge excellent support from the ESO staff at Paranal, still \noperating at reduced capacity because of the COVID pandemic, in \nparticular Eleonora Sani, Aleksandra Solarz, Rodrigo Palominos, Pedro \nFiguera and Thomas Rivinius.",
  "circularId": 31070,
  "createdOn": 1636499868000,
  "email": "d.malesani@astro.ru.nl",
  "subject": "GRB 211106A: VLT/FORS2 optical observations",
  "submitter": "Daniele B Malesani at Radboud U  <d.malesani@astro.ru.nl>",
  "eventId": "GRB 211106A"
}