2008CBET.1390....2P

M.-A. Perez-Torres, C. Romero and A. Alberdi, IAA/CSIC; L. Colina, A. Alonso-Herrero, and T. Diaz Santos, IEM/CSIC; S. Mattila and E. Kankare, Tuorla Observatory; and S. Ryder, AAO, report the detection of a compact component of radio emission in IRAS 17138-1017 at R.A. = 17h16m35s.853, Decl. = -10o20'43".05 (equinox 2000.0; estimated uncertainty 0".24 in each coordinate), using target-of-opportunity Very Large Array (VLA) observations at 1.3 cm obtained on May 19.4 UT. The flux density of this local radio maximum is 440 ± 75 mJy. The position of the radio maximum is coincident (within 0".05 in each coordinate) with the transient near-infrared source reported by Kankare et al., above, which further suggests that this object is a supernova and, given its brightness, that it must be a core-collapse supernova in its early, rising phase, as also inferred from the near-infrared observations of Kankare et al. For an assumed distance of 75 Mpc to IRAS 17138-1017, the observed flux of 2008cs corresponds to a radio luminosity of (3.1 ± 0.5) x 10**(27) erg/s/Hz. Since the radio supernova does not seem to have reached yet its maximum at wavelengths around and above 1.3 cm, further VLA observations of 2008cs at 1.3, 3.6, and 6 cm are planned to follow its time evolution and spectral evolution. Observations at other wavelengths are encouraged.