Pulsational activity of The Small-amplitude Cepheid polaris (a UMi) in 2016-2017
Дата
2017
Науковий керівник
Укладач
Редактор
Назва журналу
Номер ISSN
Номер E-ISSN
Назва тому
Видавець
Одеський національний університет імені І. І. Мечникова
Анотація
We present the results of an analysis
of 49 spectra of а UMi (Polaris) obtained during
August – December 2016 and January – March 2017.
Frequency analysis displays an unexpected decrease of
the pulsational period up to 17.3 min in comparison to
the 2015 observational set. The radial velocity amplitude
was reduced to 3.43 kms-1 in 2016 and to 3.31
kms-1 in the beginning of 2017 in comparison with
4.16 kms-1 in 2015. This result is also unexpected,
because during the last decade a gradual amplitude
growth has been observed. The average Teff = 6021
K determined from the 2016–2017 data is close to the
values determined for the 2001–2015 set.
Опис
Ключові слова
radial velocities, effective temperatures, a UMi
Бібліографічний опис
Odessa Astronomical publications = Одесские астрономические публикации = Одеські астрономічні публікації