The Tarantula Massive Binary Monitoring III. Atmosphere analysis of double-lined spectroscopic systemsx22c6;

Autor(es):Mostrar menos -

Mahy, L. ^[1] ; Sana, H. ^[1] ; Abdul-Masih, M. ^[1] ; Almeida, L. A. ^{[2, 3]} ; Langer, N. ^[4] ; Shenar, T. ^[1] ; de Koter, A. ^{[5, 1]} ; de Mink, S. E. ^{[5, 6]} ; de Wit, S. ^{[5, 7]} ; Grin, N. J. ^[4] ; Evans, C. J. ^[8] ; Moffat, A. F. J. ^{[9, 10]} ; Schneider, F. R. N. ^{[11, 12]} ; Barba, R. ^[13] ; Clark, J. S. ^[14] ; Crowther, P. ^[15] ; Graefener, G. ^[4] ; Lennon, D. J. ^{[16, 17]} ; Tramper, F. ^[7] ; Vink, J. S. ^[18]

Afiliação do(s) autor(es):Mostrar menos -

^[1] Katholieke Univ Leuven, Inst voor Sterrenkunde, Celestijnlaan 200D, Bus 2401, B-3001 Leuven - Belgium

^[2] Univ Fed Rio Grande do Norte, Dept Fis, UFRN, CP 1641, BR-59072970 Natal, RN - Brazil

^[3] Univ Estado Rio Grande do Norte, Dept Fis, Mossoro, RN - Brazil

^[4] Univ Bonn, Argelander Inst Astron, Hugel 71, D-53121 Bonn - Germany

^[5] Univ Amsterdam, Astron Inst Anton Pannekoek, Sci Pk 904, NL-1098 XH Amsterdam - Netherlands

^[6] Harvard & Smithsonian, Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 - USA

^[7] Natl Observ Athens, Penteli 15326 - Greece

^[8] Royal Observ Edinburgh, UK Astron Technol Ctr, Blackford Hill, Edinburgh EH9 3HJ, Midlothian - Scotland

^[9] Univ Montreal, Dept Phys, CP 6128, Succ C-V, Montreal, PQ H3C 3J7 - Canada

^[10] Ctr Rech Astrophys Quebec, CP 6128, Succ C-V, Montreal, PQ H3C 3J7 - Canada

^[11] Heidelberger Inst Theoret Studien, Schloss Wolfsbrunnenweg 35, D-69118 Heidelberg - Germany

^[12] Heidelberg Univ, Zentrum Astron, Astronom Rechen Inst, Monchhofstr 12-14, D-69120 Heidelberg - Germany

^[13] Univ La Serena, Dept Fis & Astron, Av Cisternas 1200 Norte, La Serena - Chile

^[14] Open Univ, Sch Phys Sci, Walton Hall, Milton Keynes MK7 6AA, Bucks - England

^[15] Univ Sheffield, Dept Phys & Astron, Hounsfield Rd, Sheffield S3 7RH, S Yorkshire - England

^[16] Inst Astrofis Canarias, Tenerife 38205 - Spain

^[17] European Space Astron Ctr, ESA, Apdo Correos 78, Madrid 28691 - Spain

^[18] Armagh Observ, Coll Hill, Armagh BT61 9DG - North Ireland

• Tipo de documento: Artigo Científico
• Fonte: Astronomy & Astrophysics; v. 634, FEB 19 2020.
• Citações Web of Science: 2

Resumo

Context. Accurate stellar parameters of individual objects in binary systems are essential to constrain the effects of binarity on stellar evolution. These parameters serve as a prerequisite to probing existing and future theoretical evolutionary models. Aims. We aim to derive the atmospheric parameters of the 31 double-lined spectroscopic binaries in the Tarantula Massive Binary Monitoring sample. This sample, composed of detached, semi-detached and contact systems with at least one of the components classified as an O-type star, is an excellent test-bed to study how binarity can impact our knowledge of the evolution of massive stars. Methods. In the present paper, 32 epochs of FLAMES/GIRAFFE spectra are analysed by using spectral disentangling to construct the individual spectra of 62 components. We then apply the CMFGEN atmosphere code to determine their stellar parameters and their helium, carbon, and nitrogen surface abundances. Results. Among the 31 systems that we study in the present paper, we identify between 48 and 77% of them as detached, likely pre-interacting systems, 16% as semi-detached systems, and between 5 and 35% as systems in or close to contact phase. Based on the properties of their components, we show that the effects of tides on chemical mixing are limited. Components on longer-period orbits show higher nitrogen enrichment at their surface than those on shorter-period orbits, in contrast to expectations of rotational or tidal mixing, implying that other mechanisms play a role in this process. For semi-detached systems, components that fill their Roche lobe are mass donors. They exhibit higher nitrogen content at their surface and rotate more slowly than their companions. By accreting new material, their companions spin faster and are likely rejuvenated. Their locations in the N - v sinx2006;i diagram tend to show that binary products are good candidates to populate the two groups of stars (slowly rotating, nitrogen-enriched objects and rapidly rotating non-enriched objects) that cannot be reproduced through single-star population synthesis. Finally, we find no peculiar surface abundances for the components in (over-)contact systems, as has been suggested by evolutionary models for tidal mixing. Conclusions. This sample, consisting of 31 massive binary systems, is the largest sample of binaries composed of at least one O-type star to be studied in such a homogeneous way by applying spectral disentangling and atmosphere modelling. The study of these objects gives us strong observational constraints to test theoretical binary evolutionary tracks. (AU)

• Processo FAPESP: 12/09716-6 - Distâncias precisas de aglomerados jovens através de binárias eclipsantes massivas
• Beneficiário: Leonardo Andrade de Almeida
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/51680-6 - Explorando o universo: da formação de galáxias aos planetas tipo-terra, com o Telescópio Gigante Magellan
• Beneficiário: João Evangelista Steiner
• Linha de fomento: Auxílio à Pesquisa - Projetos Especiais
• Processo FAPESP: 13/18245-0 - Soluções orbitais espectroscópicas completas para mais de 100 binárias massivas na região do "starburst" 30 Dourados
• Beneficiário: Leonardo Andrade de Almeida
• Linha de fomento: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado