OPTICAL IDENTIFICATION OF CEPHEIDS IN 19 HOST GALAXIES OF TYPE Ia SUPERNOVAE AND NGC 4258 WITH THEHUBBLE SPACE TELESCOPE Academic Article uri icon

abstract

  • 2016. The American Astronomical Society. All rights reserved. We present results of an optical search conducted as part of the SH0ES project (Supernovae and H 0 for the Equation of State of dark energy) for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258. The targets include nine newly imaged SN Ia hosts using a novel strategy based on a long-pass filter that minimizes the number of HST orbits required to detect and accurately determine Cepheid properties. We carried out a homogeneous reduction and analysis of all observations, including new universal variability searches in all SN Ia hosts, which yielded a total of 2200 variables with well-defined selection criteria, the largest such sample identified outside the Local Group. These objects are used in a companion paper to determine the local value of H 0 with a total uncertainty of 2.4%.

published proceedings

  • The Astrophysical Journal

author list (cited authors)

  • Hoffmann, S. L., Macri, L. M., Riess, A. G., Yuan, W., Casertano, S., Foley, R. J., ... Amanullah, R.

publication date

  • January 1, 2016 11:11 AM