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

D. G. Turner, D. J. Majaess, D. J. Lane, J. R. Percy, D. A. English, R. Huziak

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.

Ключові слова


Stars, variables, Cepheids, individual, HDE 344787.

Повний текст:

PDF (English)

Посилання


Alibert Y., Baraffe I., Hauschildt P., Allard F.: 1999,A&A, 344, 551.

Erickson R.R.: 1971,A&A, 10, 270.

ESA: 1997,The Tycho Catalogue, ESA SP-1200.

Guetter H.H.: 1992,AJ, 103, 197.

Kron G.E.: 1978,AJ, 83, 1195.

Massey P., Johnson K.E., DeGioia-Eastwood K.: 1995, ApJ, 454, 151.

Pojma´nski G.: 2002,Acta Astron., 52, 397.

Shi H.M., Hu J.Y.: 1999,A&AS, 136, 313.

Turner D.G.: 1979,JRASC, 73, 74.

Turner D.G.: 2006,Odessa Astron. Publ., 18, 115.

Turner D.G.: 2009,AIP Conf. Series, 1170, 59.

Turner D.G., Savoy J., Derrah J., Abdel-Sabour AbdelLatif M., Berdnikov L.N.: 2005,PASP, 117, 207.

Turner D.G., Abdel-Sabour Abdel-Latif M., Berdnikov L.N.: 2006,PASP, 118, 410.

Turner D.G., Kovtyukh V.V., Majaess D.J., Lane D.J., Moncrieff K.E.: 2009,AN, 330, 807.




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

Посилання

  • Поки немає зовнішніх посилань.


Copyright (c) 2016 Odessa Astronomical Publications

Creative Commons License
Ця робота ліцензована Creative Commons Attribution-NonCommercial 4.0 International License.