EFFECTIVE TEMPERATURE AND RADIAL VELOCITY OF THE SMALL AMPLITUDE CEPHEID POLARIS (alpha UMi) IN 2015
Journal Title: Odessa Astronomical Publications - Year 2016, Vol 29, Issue
Abstract
We present the results of an analysis of 21 spectra of alpha UMi (Polaris) obtained in September – December 2015. Frequency analysis shows an increase of the pulsation period up to 8.6 min in comparison to the 2007 observational set. The radial velocity amplitude comes to 4.16 kms-1, and it approximately twice the one found in 2007. The average Teff = 6017 K, and it is close to the value determined for the 2001–2004 set. Therefore Polaris moves to the red edge of the Cepheid instability strip (CIS).
Authors and Affiliations
I. A. Usenko, V. Kovtyukh, A. S. Miroshnichenko, S. Danford
Keywords
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- EP ID EP374774
- DOI 10.18524/1810-4215.2016.29.85061
- Views 58
- Downloads 0
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