• DOI:10.1088/0004-637x/745/2/156
• Corpus ID: 119113794

CEPHEID PERIOD–LUMINOSITY RELATIONS IN THE NEAR-INFRARED AND THE DISTANCE TO M31 FROM THE HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3

@article{Riess2012CEPHEIDPR,
  title={CEPHEID PERIOD–LUMINOSITY RELATIONS IN THE NEAR-INFRARED AND THE DISTANCE TO M31 FROM THE HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3},
  author={Adam G. Riess and Juergen Fliri and David Valls-Gabaud},
  journal={The Astrophysical Journal},
  year={2012},
  volume={745}
}

• A. Riess, J. Fliri, D. Valls-Gabaud
• Published 17 October 2011
• Physics
• The Astrophysical Journal

We present measurements of 68 classical Cepheids, most detected from the Canada–France–Hawaii Telescope POMME Survey, with periods from 10 to 78 days observed in the near-infrared by the Panchromatic Hubble Andromeda Treasury Program using the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). The combination of HST's resolution and the use of near-infrared measurements provide a dramatic reduction in the dispersion of the period–luminosity relation over the present optical, ground-based data. Even using random phase magnitudes we measure a dispersion of just 0.17 mag, implying a dispersion of just 0.12 mag for mean magnitudes. The error in the mean for this relation is 1% in distance. Combined with similar observations of Cepheids in other hosts and independent distance determinations, we measure a distance to M31 of μ0 = 24.38  ±  0.06(statistical)  ±  0.03(systematic), 752 ± 27 kpc, in good agreement with past measurements though with a better, 3% precision here. The result is also in good agreement with independent distance determinations from two detached eclipsing binaries allowing for an independent calibration of the Cepheid luminosities and a determination of the Hubble constant.