Dominion Astrophysical Observatory

About: Dominion Astrophysical Observatory is a facility organization based out in Victoria, British Columbia, Canada. It is known for research contribution in the topics: Galaxy & Stars. The organization has 244 authors who have published 554 publications receiving 20305 citations. The organization is also known as: DAO.

A New Method for the Determination of the Hubble Parameter

Abstract: By chance, the slope of the Mv(max) versus (B-V)max relation for recent theoretical models of supernovae of Type Ia (SNe Ia) by Hoflich & Khokhlov is indistinguishable from the slope of a reddening line in the V versus B-V plane. This coincidence allows one to determine a parameter Mv*(max) for SNe Ia that is independent of both supernova detonation model and of interstellar reddening. Calibrating Mv*(max) with observations of SNe Ia by Hamuy et al. yields values of the Hubble parameter Ho in the range 55 - 60 km s-1 Mpc-1 . The discrepancy between this result, and values of Ho recently obtained from observations of Cepheids in the Virgo cluster, suggests that either (1) the Cepheid distance scale is wrong, (2) the SN Ia models of Hoflich & Khokhlov are too bright by ~ 0.75 mag near maximum light, or (3) their models are too red by \~ 0.25 mag in B-V.

Holographic Beam Mapping of the CHIME Pathfinder Array

Abstract: The Canadian Hydrogen Intensity Mapping Experiment (CHIME) Pathfinder radio telescope is currently surveying the northern hemisphere between 400 and 800 MHz. By mapping the large scale structure of neutral hydrogen through its redshifted 21 cm line emission between $z \sim 0.8-2.5$ CHIME will contribute to our understanding of Dark Energy. Bright astrophysical foregrounds must be separated from the neutral hydrogen signal, a task which requires precise characterization of the polarized telescope beams. Using the DRAO John A. Galt 26 m telescope, we have developed a holography instrument and technique for mapping the CHIME Pathfinder beams. We report the status of the instrument and initial results of this effort.

A high-resolution study of superficially normal late B spectra.

Abstract: High-dispersion observations of 13 sharp-lined spectra of late B stars are intercompared. All stars had MK types and appeared superficially normal. Two of these objects are clearly related to the manganese stars, while a third may be a 'hot, hot Am'. The selection effect arising from the difficulty of detecting mild hot manganese stars is discussed.

The CNOC2 Field Galaxy Redshift Survey

Abstract: This paper provides a brief description of the CNOC2 Redshift Survey being carried out at CFHT, giving the scope, technique, and current status of the survey, and some preliminary results.