Supernova 1991T and the value of the Hubble constant

Based on multiepoch Hubble Space Telescope observations, we present the discovery of 16 high-quality Cepheid candidates in NGC 4527. Corrected for metallicity effects in the Cepheid period-luminosity relation, we derive a distance, including both random (r) and systematic (s) uncertainties, of 13.0 +/- 0.5(r) +/- 1.2(s) Mpc. Our result is then used to provide a calibration of the peak B-, V-, and I- band luminosities of the peculiar Type Ia supernova SN 1991T, a resident of NGC 4527. Despite its documented spectroscopic peculiarities, after correction for the decline rate-luminosity correlation, the corrected peak luminosity is indistinguishable from those of so-called normal Type Ia SNe. With nine local calibrators now at our disposal, we determine a robust value for the Hubble constant of H-0 = 73 +/- 2(r) +/- 7(s) km s(-1) Mpc(-1).