Results of Photometric and Spectroscopic Observations of the Young Variable Star V730 Cep
| Autor: | David Mkrtichian, V. P. Grinin, I. S. Potravnov, K. A. Antonyuk |
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| Rok vydání: | 2018 |
| Předmět: |
Physics
Brightness 010504 meteorology & atmospheric sciences Be star Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences Photometry (optics) Stars T Tauri star Space and Planetary Science 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Circumstellar dust Astrophysics::Earth and Planetary Astrophysics Variable star Spectroscopy 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics 0105 earth and related environmental sciences |
| Zdroj: | Astronomy Letters. 44:798-802 |
| ISSN: | 1562-6873 1063-7737 |
| DOI: | 10.1134/s1063773718120022 |
| Popis: | We present the results of our photometric (V RI) and spectroscopic observations of the young variable star V730 Cep (MisV1147) classified by Uemura et al. (2004) as a Herbig Be star. Our photometry confirms the conclusion of the above authors that this star has a complex pattern of variability including periodic or quasi-periodic brightness variations with a period of about 14 days and deep Algol-like minima typical for UX Ori stars. Our spectroscopy shows that the classification of V730 Cep as a Herbig Be star is wrong. Actually, this star has a much lower temperature and belongs to the family of T Tauri stars. This allows us to explain the nature of the unusual photometric activity of V730 Cep based on a combination of two well-known models of variable circumstellar extinction applied to young stars: AA Tau- and UX Oritype variability. It follows from our observations that the color tracks on the V −(V −I) color–magnitude diagram for these models slightly differ: the AA Tau-type variability of circumstellar extinction is caused by larger grains than the UX Ori-type variability. Such a difference can be due to an increase in the characteristic sizes of circumstellar dust as the star is approached and has a simple explanation: small dust grains evaporate faster than large ones. |
| Databáze: | OpenAIRE |
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