SCYON Abstract

Received on February 21 2012

Discovery of the Host Cluster for the Fundamental Cepheid Calibrator Zeta Gem

AuthorsD. Majaess (1,4), D. Turner (1,4,5,6), W. Gieren (2), D. Balam (3), and D. Lane (1,4)
Affiliation(1) Saint Mary's University, Halifax, NS, Canada
(2) Universidad de Concepcion, Concepcion, Chile
(3) Dominion Astrophysical Observatory, Victoria, BC, Canada
(4) Abbey Ridge Observatory, Halifax, Nova Scotia, Canada
(5) Visiting Astronomer, David Dunlap Observatory
(6) Visiting Astronomer, Kitt Peak National Observatory
To appear inApJ Letters
Contactdmajaess@ap.smu.ca
URLhttp://arxiv.org/abs/1202.2363
Links

Abstract

New and existing CORAVEL, UBVJHKs, HST, HIP/Tycho, ARO, KPNO, and DAO observations imply that the fundamental Cepheid calibrator Zeta Gem is a cluster member. The following parameters were inferred for Zeta Gem from cluster membership and are tied to new spectral classifications (DAO) established for 26 nearby stars (e.g., HD53588/B7.5IV, HD54692/B9.5IV): E(B-V)=0.02+-0.02, log t=7.85+-0.15, and d=355+-15 pc. The mean distance to Zeta Gem from cluster membership and six recent estimates (e.g., IRSB) is d=363+-9(se)+-26(sd) pc. The results presented here support the color-excess and HST parallax derived for the Cepheid by Benedict et al. (2007). Forthcoming precise proper motions (DASCH) and Chandra/XMM-Newton observations of the broader field may be employed to identify cluster members, bolster the cluster's existence, and provide stronger constraints on the Cepheid's fundamental parameters.