Photometry and spectroscopy of massive stars observed during K2 Campaign 8

Autor(es)

Eidam, Jessica M. ^{[1, 2]} ; Andrade, Laerte ^[1] ; Emilio, Marcelo ^{[1, 2, 3]} ; Cristina Rabello-Soares, M. ^[4] ; Pereira, Alan W. ^{[1, 2]} ; Janot-Pacheco, Eduardo ^[5] ; Armstrong, James D. ^[3]

Afiliação do(s) autor(es)

^[1] Univ Estadual Ponta Grossa, BR-84030900 Ponta Grossa, PR - Brazil

^[2] Observ Nacl, MCTIC, BR-20921400 Rio De Janeiro, RJ - Brazil

^[3] Univ Hawaii, Inst Astron, Maui, HI 96768 - USA

^[4] Univ Fed Minas Gerais, Phys Dept, BR-31270901 Belo Horizonte, MG - Brazil

^[5] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05509090 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 491, n. 1, p. 302-312, JAN 2020.
• Citações Web of Science: 0

Resumo

We report in this paper spectroscopic and photometric analysis of eight massive stars observed during Campaign 8 of the Kepler/K2 mission from 2016 January to March. Spectroscopic data were obtained on these stars at OPD/LNA, Brazil, and their stellar parameters determined using SME. Periodic analyses of the light curves were performed through CLEANEST and PERIOD04 algorithms. Mass, luminosity, and radius of our stars were estimated employing CESAM + POSC grids. Three of our stars show significant periodicity. K2 ID 220679442 and K2 ID 220532854 have periods linked to the stellar rotation. K2 ID 220532854 has prominent silicon lines (Si II 4128-4131 angstrom), a characteristic presented in the peculiar class of Ap magnetic main-sequence stars. However, in our spectral analysis, this object was found to be an evolved, luminous giant star. K2 ID 220466722 was revealed to be a delta Scuti variable, and 40 individual frequencies were determined for this star. No significant periodicity was found in the light curves for the remaining stars analysed in this work, besides the instrumental one. (AU)

• Processo FAPESP: 16/13750-6 - O Brasil no espaço: Astrofísica e Engenharia
• Beneficiário: Eduardo Janot Pacheco
• Modalidade de apoio: Auxílio à Pesquisa - Projetos Especiais