{
  "bibcode": "2009GCN..9033....1K",
  "body": "D. A. Kann, U. Laux and B. Stecklum (TLS Tautenburg) report:\n\nWe observed the afterglow (Updike et al., GCN 9026, Cenko et al. GCN 9027) \nof the intense Fermi GBM/LAT GRB 090323 (Ohno et al., GCN 9021) with the \n1.34m Schmidt telescope of the TLS Tautenburg observatory under inclement \nconditions (low transparency, passing clouds). We obtained 8 Rc frames of \n600 seconds exposure time each before clouds shut us down. The afterglow \nis faintly detected in each single image and clearly detected in the \ncomplete stack.\n\nAssuming the star at RA = 12 42 39.3, Dec. = +17 05 05.7 to have Rc = \n17.15 (USNOR1=17.17, USNOR2=17.12), we measure the following afterglow \nmagnitude:\n\ndays after trigger\tRc\tdRc (statistical)\n\n1.87751\t\t\t20.88\t0.04\n\nThis value is only slightly fainter than those reported ~18 hours earlier \n(Updike et al., GCN 9026, Cenko et al. GCN 9027), which may indicate the \nfollowing:\n\n- The afterglow is undergoing a plateau phase or possibly even a \nrebrightening (if it faded more inbetween).\n- The magnitude of the comparison star is highly incorrect (e.g., variable \nstar). But we also used several other comparison stars and find agreement \nwithin +/- 0.2 mags.\n\nIf the afterglow truly is this bright, this makes it one of the most \nluminous afterglows every detected, comparable or even exceeding the \nrecent GRB 090313 (Perley et al., GCN 8985, de Ugarte Postigo et al., \n8992). The very low foreground extinction, excellent observability, low \ninfluence of moonlight combined with the extreme high energy properties \n(possible several ksec long tail emission in LAT, Ohno et al., GCN 9021, \nextremely high isotropic energy release, Golenetskii et al., GCN 9030) and \nthe spectroscopic redshift (Chornock et al., GCN 9028) make this a GRB of \nspecial interest, and more observations, especially with medium-size \ntelescopes, are encouraged. If weather permits, Tautenburg will continue \nobservations.\n\nThis message may be cited.",
  "circularId": 9033,
  "createdOn": 1237941722000,
  "email": "kann@tls-tautenburg.de",
  "subject": "GRB 090323 TLS detection - still bright",
  "submitter": "Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>",
  "eventId": "GRB 090323"
}