S. Klose, B. Stecklum (Thüringer Landessternwarte Tautenburg),
O. Fischer (Universitäts-Sternwarte Jena),
J. Greiner (AIP Potsdam),
S. Hippler (Max-Planck-Institut für Astronomie, Heidelberg),
R. Davies (Max-Planck-Institut für Extraterrestrische Physik, Garching),
L. Montoya (Calar Alto observatory),
F. J. Vrba, A. A. Henden, C. B. Luginbuhl, B. Canzian, S. E. Levine, H. H. Guetter, J. A. Munn (U.S. Naval Observatory, Flagstaff),
D. H. Hartmann (Clemson University, Clemson),
A. Castro-Tirado (LAEFF-INTA, Madrid, and IAA-CSIC, Granada),
J. Gorosabel (LAEFF-INTA, Madrid, and University of Amsterdam),
J. M. Castro-Ceron (ROA), and
M. R. Zapatero-Osorio, D. M. Delgado, S. Chueca, M. J. Arevalo (IAC, Tenerife)

report:

The refined error box of GRB 000615 (Gandolfi et al. GCN 705) was imaged in two successive runs with the Calar Alto 3.5-m telescope on June 15, 22:09 UT - 00:25 UT using the near-infrared camera Omega Cass (see http://www.mpia-hd.mpg.de/ ) in the polarimetric mode. The limiting magnitude of either K'-band image is about K'=19 after adding all frames taken at different position angles of the wire-grid polarizer.

A red source in the GRB error box with no counterpart on the DSS-2 red image is at RA, DEC (J2000) = 15:32:35.16, 73:50:45.2 (+/- 1 arcsec). We estimate its magnitude K'=19. Further data reduction is in progress, the K'-band magnitude can be improved. This source is also barely visible on an R-band image taken at USNO with the 1.0-m telescope on June 16, 03:48 UT (limiting magnitude about R=21). It is also visible as a faint source on an I-band image taken with the IAC 80 telescope on June 15.9 UT (limiting magnitude about 20.5). We note we do not claim that this is a fading source, since second epoch K'-band data are not available. At the present stage we cannot rule out that this is a faint Galactic star with an R-K color of about 2 mag.

Figure 1: K'-band image of the error box of GRB 000615. The source mentioned in the text is indicated.

Any use of these data should be accompanied by a reference.

S. Klose, B. Stecklum, Thüringer Landessternwarte Tautenburg.

Last modified: June 18, 2000