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Title: THE M31 NEAR-INFRARED PERIOD-LUMINOSITY RELATION AND ITS NON-LINEARITY FOR δ Cep VARIABLES WITH 0.5 ≤ log (P) ≤ 1.7

We present the largest M31 near-infrared (F110W (close to J band), F160W (H band)) Cepheid sample so far. The sample consists of 371 Cepheids with photometry obtained from the Hubble Space Telescope PHAT program. The sample of 319 fundamental mode Cepheids, 16 first overtone Cepheids, and 36 type II Cepheids was identified using the median absolute deviation outlier rejection method we develop here. This method does not rely on priors and allows us to obtain this clean Cepheid sample without rejecting a large fraction of Cepheids. The obtained period-luminosity relations (PLRs) have a very small dispersion, i.e., 0.155 mag in F160W, despite using random phased observations. This remarkably small dispersion allows us to determine that the PLRs are significantly better described by a broken slope at 10 days than a linear slope. The use of our sample as an anchor to determine the Hubble constant gives a 3.2% larger Hubble constant compared to the Riess et al. sample.
Authors:
; ; ; ;  [1] ; ; ; ;  [2] ;  [3]
  1. University Observatory Munich, Scheinerstrasse 1, D-81679 Munich (Germany)
  2. Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching (Germany)
  3. Departamento de Astronomia, Universidad de Concepciòn, Casilla 160-C, Concepciòn (Chile)
Publication Date:
OSTI Identifier:
22364380
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 799; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CATALOGS; CEPHEIDS; COMPARATIVE EVALUATIONS; DISTANCE; GALAXIES; LUMINOSITY; NEAR INFRARED RADIATION; PHOTOMETRY; RANDOMNESS; SPACE; TELESCOPES