A spectroscopic and photometric investigation of the mercury–manganese star KIC 6128830
| Autor: | D. Drobek, Ewa Niemczura, Przemysław Walczak, Klaus Bernhard, Simon J. Murphy, Ernst Paunzen, Stefan Hümmerich |
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| Rok vydání: | 2017 |
| Předmět: |
Physics
010308 nuclear & particles physics FOS: Physical sciences Astronomy Astronomy and Astrophysics Astrophysics Mercury-manganese star 01 natural sciences Spectral line Photometry (optics) Stars Amplitude Astrophysics - Solar and Stellar Astrophysics 13. Climate action Space and Planetary Science 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) Astrophysics::Galaxy Astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 474:2467-2478 |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/stx2974 |
| Popis: | The advent of space-based photometry provides the opportunity for the first precise characterizations of variability in Mercury-Manganese (HgMn/CP3) stars, which might advance our understanding of their internal structure. We have carried out a spectroscopic and photometric investigation of the candidate CP3 star KIC 6128830. A detailed abundance analysis based on newly-acquired high-resolution spectra was performed, which confirms that the star's abundance pattern is fully consistent with its proposed classification. Photometric variability was investigated using four years of archival Kepler data. In agreement with results from the literature, we have identified a single significant and independent frequency $f_1$=0.2065424 d$^{-1}$ with a peak-to-peak amplitude of $\sim$3.4 mmag and harmonic frequencies up to $5f_1$. Drawing on the predictions of state-of-the-art pulsation models and information on evolutionary status, we discuss the origin of the observed light changes. Our calculations predict the occurrence of g-mode pulsations at the observed variability frequency. On the other hand, the strictly mono-periodic nature of the variability strongly suggests a rotational origin. While we prefer the rotational explanation, the present data leave some uncertainty. 13 pages, 13 figures, accepted for publication in MNRAS |
| Databáze: | OpenAIRE |
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