THE MID-INFRARED TULLY-FISHER RELATION: CALIBRATION OF THE TYPE Ia SUPERNOVA SCALE AND H0

This Letter builds on a calibration of the Type Ia supernova (SNIa) absolute distance scale begun with a core of distances based on the correlation between galaxy rotation rates and optical I-C-band photometry. This new work extends the calibration through the use of mid-infrared photometry acquired at 3.6 mu m with the Spitzer Space Telescope. The great virtue of the satellite observations is the constancy of the photometry at a level better than 1% across the sky. The new calibration is based on 39 individual galaxies and 8 clusters that have been the sites of well-observed SNIa. The new 3.6 mu m calibration is not yet as extensively based as the I-C-band calibration but is already sufficient to justify a preliminary report. Distances based on the mid-infrared photometry are 2% greater in the mean than reported at the I-C-band. This difference is only marginally significant. The I-C-band result is confirmed with only a small adjustment. Incorporating a 1% decrease in the Large Magellanic Cloud distance, the present study indicates H-0 = 75.2 +/- 3.0 km s(-1) Mpc(-1).