{
  "bibcode": "2015GCN.18567....1O",
  "body": "Arto Oksanen (Hankasalmi Obs., Hankasalmi, Finland) reports the \nfollowing observations of GRB 151027A (Maselli et al. 2015, GCN Circular \n#18478; Zheng et al. 2015, GCN Circular #18479, and many subsequent \nCirculars) to the AAVSO High Energy Network:\n\nA. Oksanen observed the location of GRB 151027A using the Hankasalmi \nObservatory 0.4-m Richey-Chretien telescope using an SBIG STL-1001E \ncamera.  Time-series images were obtained with both Rc and clear \nfilters, with fifty 60-second frames obtained in each filter.  Clear \nfiltered images were obtained between 16:27:07 UT and 22:01:23 UT on \n2015 October 27, and Rc-filtered images were obtained between 18:59:58 \nand 21:45.04 UT.  Photometry was performed using an ensemble of \ncomparison stars with APASS photometry available from AAVSO VSP \n(www.aavso.org/vsp). The afterglow is detected in both Rc- and \nclear-filtered observations, with evidence of fading between the start \nand end of the observing run.\n\nPhotometry of co-added groups of images yields the following:\n\nClear filter:\n\nt-t0(d)     m(CR)     err(CR)\n0.5235      16.872    0.030\n0.5334      16.816    0.030\n0.6531      17.160    0.044\n0.6644      17.322    0.047\n0.7468      17.575    0.065\n\n\nRc filter:\n\nt-t0(d)     m(R)     err(R)\n0.6365      17.257    0.058\n0.6848      17.544    0.074\n0.7353      17.580    0.118\n\nThese magnitudes of GRB 151027A are consistent with other magnitudes \nobtained at similar epochs of this burst (e.g. Hentunen et al. GCN \nCircular #18503; Sonbas et al. #18518).",
  "circularId": 18567,
  "createdOn": 1446973494000,
  "email": "oksanen@nyrola.jklsirius.fi",
  "subject": "GRB 151027A: Hankasalmi optical observations",
  "submitter": "Arto Oksanen at Nyrola Obs., Finland  <oksanen@nyrola.jklsirius.fi>",
  "eventId": "GRB 151027A"
}