2006CBET..396....1S

C. J. Stockdale and M. Kelley, Marquette University; R. A. Sramek, National Radio Astronomy Observatory; S. D. Van Dyk, Spitzer Science Center, California Institute of Technology; S. Immler, Goddard Space Flight Center and Universities Space Research Association; K. W. Weiler and C. L. M. Williams, Naval Research Laboratory; and N. Panagia, Space Telescope Science Institute, report the lack of detection of radio emission near the position of supernova 2006X (cf. IAUC 8667, CBET 393) with the Very Large Array: "Upper limits (3 sigma) to any radio flux density were established on Feb. 9.37 UT of < 0.162 mJy (spectral luminosity < 5.6 x 10**25 erg/s/Hz) at 22.460 GHz (wavelength 1.3 cm) and < 0.047 mJy (spectral luminosity < 1.5 x 10**25 erg/s/Hz) at 8.460 GHz (wavelength 3.5 cm), among the deepest and earliest limits yet obtained for radio emission from a type-Ia supernova. Under standard assumptions, this implies a mass-loss rate from the pre-supernova system of < (a few) x 10**-8 solar mass per year. The search for radio emission was conducted within about 10" of the published optical position of SN 2006X (R.A. = 12h22m53s.99, Decl. = +15o48'33".1, equinox 2000.0; IAUC 8667), and no radio emission was detected near the supernova position exceeding three times the map rms at any of the times or in any of the frequency bands listed above."