Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column

Astronomy and Astrophysics 580 (2015): A82 reproduced with permission from Astronomy & Astrophysics

Detalles Bibliográficos
Autores: Sicilia-Aguilar, Aurora, Fang, Min, Roccatagliata, Veronica, Cameron, Andrew Collier, Kóspál, Ágnes, Henning, Thomas, Ábrahám, Peter, Sipos, Nikoletta
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/671140
Acceso en línea:http://hdl.handle.net/10486/671140
https://dx.doi.org/10.1051/0004-6361/201525970
Access Level:acceso abierto
Palabra clave:Accretion, accretion disks
Protoplanetary disks
Stars: individual: EX Lupi
Stars: pre-main sequence
Stars: variables: T Tauri, Herbig Ae/Be
Techniques: spectroscopic
Astronomía
Física
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spelling Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion columnSicilia-Aguilar, AuroraFang, MinRoccatagliata, VeronicaCameron, Andrew CollierKóspál, ÁgnesHenning, ThomasÁbrahám, PeterSipos, NikolettaAccretion, accretion disksProtoplanetary disksStars: individual: EX LupiStars: pre-main sequenceStars: variables: T Tauri, Herbig Ae/BeTechniques: spectroscopicAstronomíaFísicaAstronomy and Astrophysics 580 (2015): A82 reproduced with permission from Astronomy & AstrophysicsContext. EX Lupi is a young, accreting M0 star and the prototype of EXor variable stars. Its spectrum is very rich in emission lines, including many metallic lines with narrow and broad components. The presence of a close companion has also been proposed, based on radial velocity signatures. Aims. We use the metallic emission lines to study the accretion structures and to test the companion hypothesis. Methods. We analyse 54 spectra obtained during five years of quiescence time. We study the line profile variability and the radial velocity of the narrow and broad metallic emission lines. We use the velocity signatures of different species with various excitation conditions and their time dependency to track the dynamics associated with accretion. Results. We observe periodic velocity variations in the broad and the narrow line components, consistent with rotational modulation. The modulation is stronger for lines with higher excitation potentials (e.g. He II), which are likely produced in a confined area very close to the accretion shock. Conclusions. We propose that the narrow line components are produced in the post-shock region, while the broad components originate in the more extended, pre-shock material in the accretion column. All the emission lines suffer velocity modulation due to the rotation of the star. The broad components are responsible for the line-dependent veiling observed in EX Lupi. We demonstrate that a rotationally modulated line-dependent veiling can explain the radial velocity signature of the photospheric absorption lines, making the close-in companion hypothesis unnecessary. The accretion structure is locked to the star and very stable during the five years of observations. Not all stars with similar spectral types and accretion rates show the same metallic emission lines, which could be related to differences in temperature and density in their accretion structure(s). The contamination of photospheric signatures by accretion-related processes can be turned into a very useful tool for determining the innermost details of the accretion channels in the proximity of the star. The presence of emission lines from very stable accretion columns will nevertheless be a very strong limitation for the detection of companions by radial velocity in young stars, given the similarity of the accretion-related signatures with those produced by a companionA.S.A. and M.F. acknowledge support from the Spanish “Proyectos de investigación no orientada” project number AYA2012-35008. A.K. is partly supported by the Momentum grant of the MTA CSTK Lendület Disk Research Group. P.Á. acknowledges support from the Hungarian Research Grant OTKA 101393EDP SciencesDepartamento de Física TeóricaFacultad de Ciencias20152015-08-01research articlehttp://purl.org/coar/resource_type/c_2df8fbb1VoRhttp://purl.org/coar/version/c_970fb48d4fbd8a85info:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10486/671140https://dx.doi.org/10.1051/0004-6361/201525970reponame:Biblos-e Archivo. Repositorio Institucional de la UAMinstname:Universidad Autónoma de MadridInglésengopen accesshttp://purl.org/coar/access_right/c_abf2info:eu-repo/semantics/openAccessoai:repositorio.uam.es:10486/6711402026-06-23T12:46:27Z
dc.title.none.fl_str_mv Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
title Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
spellingShingle Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
Sicilia-Aguilar, Aurora
Accretion, accretion disks
Protoplanetary disks
Stars: individual: EX Lupi
Stars: pre-main sequence
Stars: variables: T Tauri, Herbig Ae/Be
Techniques: spectroscopic
Astronomía
Física
title_short Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
title_full Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
title_fullStr Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
title_full_unstemmed Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
title_sort Accretion dynamics of EX Lupi in quiescence: The star, the spot, and the accretion column
dc.creator.none.fl_str_mv Sicilia-Aguilar, Aurora
Fang, Min
Roccatagliata, Veronica
Cameron, Andrew Collier
Kóspál, Ágnes
Henning, Thomas
Ábrahám, Peter
Sipos, Nikoletta
author Sicilia-Aguilar, Aurora
author_facet Sicilia-Aguilar, Aurora
Fang, Min
Roccatagliata, Veronica
Cameron, Andrew Collier
Kóspál, Ágnes
Henning, Thomas
Ábrahám, Peter
Sipos, Nikoletta
author_role author
author2 Fang, Min
Roccatagliata, Veronica
Cameron, Andrew Collier
Kóspál, Ágnes
Henning, Thomas
Ábrahám, Peter
Sipos, Nikoletta
author2_role author
author
author
author
author
author
author
dc.contributor.none.fl_str_mv Departamento de Física Teórica
Facultad de Ciencias
dc.subject.none.fl_str_mv Accretion, accretion disks
Protoplanetary disks
Stars: individual: EX Lupi
Stars: pre-main sequence
Stars: variables: T Tauri, Herbig Ae/Be
Techniques: spectroscopic
Astronomía
Física
topic Accretion, accretion disks
Protoplanetary disks
Stars: individual: EX Lupi
Stars: pre-main sequence
Stars: variables: T Tauri, Herbig Ae/Be
Techniques: spectroscopic
Astronomía
Física
description Astronomy and Astrophysics 580 (2015): A82 reproduced with permission from Astronomy & Astrophysics
publishDate 2015
dc.date.none.fl_str_mv 2015
2015-08-01
dc.type.none.fl_str_mv research article
http://purl.org/coar/resource_type/c_2df8fbb1
VoR
http://purl.org/coar/version/c_970fb48d4fbd8a85
dc.type.openaire.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv http://hdl.handle.net/10486/671140
https://dx.doi.org/10.1051/0004-6361/201525970
url http://hdl.handle.net/10486/671140
https://dx.doi.org/10.1051/0004-6361/201525970
dc.language.none.fl_str_mv Inglés
eng
language_invalid_str_mv Inglés
language eng
dc.rights.none.fl_str_mv open access
http://purl.org/coar/access_right/c_abf2
dc.rights.openaire.fl_str_mv info:eu-repo/semantics/openAccess
rights_invalid_str_mv open access
http://purl.org/coar/access_right/c_abf2
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv EDP Sciences
publisher.none.fl_str_mv EDP Sciences
dc.source.none.fl_str_mv reponame:Biblos-e Archivo. Repositorio Institucional de la UAM
instname:Universidad Autónoma de Madrid
instname_str Universidad Autónoma de Madrid
reponame_str Biblos-e Archivo. Repositorio Institucional de la UAM
collection Biblos-e Archivo. Repositorio Institucional de la UAM
repository.name.fl_str_mv
repository.mail.fl_str_mv
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score 15,223283

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