HDE 344787, THE POLARIS ANALOGUE THAT IS EVEN MORE INTERESTING THAN POLARIS

Автор(и)

  • D. G. Turner Department of Astronomy and Physics, Saint Mary’s University, Halifax, Nova Scotia, Canada; Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatories, which is operated by the Associated Universities for Research in Astronomy, Inc. (AURA) under contract with the National Science Foundation; Visiting Astronomer, Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada; Visiting Astronomer, Harvard College Observatory Photographic Plate Stacks;, Канада
  • D. J. Majaess Department of Astronomy and Physics, Saint Mary’s University, Halifax, Nova Scotia, Canada ; The Abbey Ridge Observatory, Stillwater Lake, Nova Scotia, Canada, Канада
  • D. J. Lane Department of Astronomy and Physics, Saint Mary’s University, Halifax, Nova Scotia, Canada ; The Abbey Ridge Observatory, Stillwater Lake, Nova Scotia, Canada, Канада
  • J. R. Percy Erindale College, University of Toronto, Erindale, Ontario, Canada; Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatories, which is operated by the Associated Universities for Research in Astronomy, Inc. (AURA) under contract with the National Science Foundation, Канада
  • D. A. English Sir Wilfred Grenfell College, Memorial University, Corner Brook, Newfoundland, Canada; Visiting Astronomer, Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada, Канада
  • R. Huziak SED Systems, Saskatoon, Saskatchewan, Canada, Канада

DOI:

https://doi.org/10.18524/1810-4215.2010.23.85250

Ключові слова:

Stars, variables, Cepheids, individual, HDE 344787.

Анотація

A collection of active photometric
observations over the last half decade, archival data
from the past 120 years, radial velocity observations
from 1984, and recent monitoring through a pro-am
collaboration reveal that the 9th magnitude F9 Ib
supergiant HDE 344787 is a double-mode Cepheid
variable of extremely small amplitude. It displays remarkably
similar, but much more extreme, properties
to the exotic Cepheid Polaris, including a rapidlyincreasing
period and sinusoidal light variations of
decreasing amplitude suggesting that pulsational
stability may occur as early as 2045. Unlike Polaris,
HDE 344787 displays sinusoidal light variations at
periods of both 5<sub>d</sub>.4 and 3<sub>d</sub>.8 days, corresponding to
canonical fundamental mode and overtone pulsation.
But it may be similar to Polaris in helping to define a
small subgroup of Cepheids that display characteristics
consistent with a first crossing of the instability strip.
An update of 2010 observations of this remarkable
star is presented.

Посилання

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Опубліковано

2010-12-02

Номер

Том 23 (2010)

Розділ

Статті

Ліцензія

Авторське право (c) 2016 Odessa Astronomical Publications

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Відповідно Закону України про авторське право і суміжні права N 3792-XII від 23 грудня 1993 року