Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars?
Autor(a) principal: | |
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Data de Publicação: | 2016 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFRGS |
Texto Completo: | http://hdl.handle.net/10183/150008 |
Resumo: | Context. The discovery of pulsations in low-mass stars opens an opportunity to probe their interiors and determine their evolution by employing the tools of asteroseismology. Aims. We aim to analyse high-speed photometry of SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25 and discover brightness variabilities. In order to locate these stars in the Te log g diagram, we fit optical spectra (SDSS) with synthetic nonmagnetic spectra derived from model atmospheres. Methods. To carry out this study, we used the photometric data we obtained for these stars with the 2.15 m telescope at CASLEO, Argentina. We analysed their light curves and applied the discrete Fourier transform (FT) to determine the pulsation frequencies. Finally, we compare both stars in the Te log g diagram, with two known pre-white dwarfs and seven pulsating pre-ELM white dwarf stars, Scuti, and SX Phe stars Results. We report the discovery of pulsations in SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25. We determine their e ective temperature and surface gravity to be Te = 7972 200 K, log g = 4:25 0:5 and Te = 7925 200 K, log g = 4:25 0:5, respectively. With these parameters, these new pulsating low-mass stars can be identified with either ELM white dwarfs (with 0:17 M ) or more massive SX Phe stars. We identified pulsation periods of 3278.7 and 1633.9 s for SDSS J145847.02+070754.46 and a pulsation period of 3367.1 s for SDSS J173001.94+070600.25. These two new objects, together with those of Maxted et al. (2013, 2014), indicate the possible existence of a new instability domain towards the late stages of evolution of low-mass white dwarf stars, although their identification with SX Phe stars cannot be discarded. |
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Corti, Mariela AlejandraKanaan Neto, Antonio NemerCórsico, Alejandro HugoKepler, Souza OliveiraAlthaus, Leandro GabrielKoester, DetlevSánchez Arias, J. P.2016-12-07T02:26:39Z20160004-6361http://hdl.handle.net/10183/150008001006140Context. The discovery of pulsations in low-mass stars opens an opportunity to probe their interiors and determine their evolution by employing the tools of asteroseismology. Aims. We aim to analyse high-speed photometry of SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25 and discover brightness variabilities. In order to locate these stars in the Te log g diagram, we fit optical spectra (SDSS) with synthetic nonmagnetic spectra derived from model atmospheres. Methods. To carry out this study, we used the photometric data we obtained for these stars with the 2.15 m telescope at CASLEO, Argentina. We analysed their light curves and applied the discrete Fourier transform (FT) to determine the pulsation frequencies. Finally, we compare both stars in the Te log g diagram, with two known pre-white dwarfs and seven pulsating pre-ELM white dwarf stars, Scuti, and SX Phe stars Results. We report the discovery of pulsations in SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25. We determine their e ective temperature and surface gravity to be Te = 7972 200 K, log g = 4:25 0:5 and Te = 7925 200 K, log g = 4:25 0:5, respectively. With these parameters, these new pulsating low-mass stars can be identified with either ELM white dwarfs (with 0:17 M ) or more massive SX Phe stars. We identified pulsation periods of 3278.7 and 1633.9 s for SDSS J145847.02+070754.46 and a pulsation period of 3367.1 s for SDSS J173001.94+070600.25. These two new objects, together with those of Maxted et al. (2013, 2014), indicate the possible existence of a new instability domain towards the late stages of evolution of low-mass white dwarf stars, although their identification with SX Phe stars cannot be discarded.application/pdfengAstronomy and astrophysics. Les Ulis. Vol. 587 (Mar. 2016), L5, 4 p.AsterosismologiaFotometria estelarPulsacoes estelaresAnãs brancasEvolucao estelarEstrelas variaveisWhite dwarfsStars: individual: SDSSJ145847.02+070754.46Stars: individual: SDSSJ173001.94+070600.25Stars: low-massTwo new pulsating low-mass pre-white dwarfs or SX Phoenicis stars?Estrangeiroinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFRGSinstname:Universidade Federal do Rio Grande do Sul (UFRGS)instacron:UFRGSORIGINAL001006140.pdf001006140.pdfTexto completo (inglês)application/pdf342157http://www.lume.ufrgs.br/bitstream/10183/150008/1/001006140.pdf887fbac0726899c48d210b0181ac3855MD51TEXT001006140.pdf.txt001006140.pdf.txtExtracted Texttext/plain22540http://www.lume.ufrgs.br/bitstream/10183/150008/2/001006140.pdf.txt0319517eba51ea3dbf7558fb44d0b8c5MD52THUMBNAIL001006140.pdf.jpg001006140.pdf.jpgGenerated Thumbnailimage/jpeg1920http://www.lume.ufrgs.br/bitstream/10183/150008/3/001006140.pdf.jpg8dc2db9969c5f44c11103118fb060b2eMD5310183/1500082018-10-29 09:27:57.16oai:www.lume.ufrgs.br:10183/150008Repositório de PublicaçõesPUBhttps://lume.ufrgs.br/oai/requestopendoar:2018-10-29T12:27:57Repositório Institucional da UFRGS - Universidade Federal do Rio Grande do Sul (UFRGS)false |
dc.title.pt_BR.fl_str_mv |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
title |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
spellingShingle |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? Corti, Mariela Alejandra Asterosismologia Fotometria estelar Pulsacoes estelares Anãs brancas Evolucao estelar Estrelas variaveis White dwarfs Stars: individual: SDSSJ145847.02+070754.46 Stars: individual: SDSSJ173001.94+070600.25 Stars: low-mass |
title_short |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
title_full |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
title_fullStr |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
title_full_unstemmed |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
title_sort |
Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? |
author |
Corti, Mariela Alejandra |
author_facet |
Corti, Mariela Alejandra Kanaan Neto, Antonio Nemer Córsico, Alejandro Hugo Kepler, Souza Oliveira Althaus, Leandro Gabriel Koester, Detlev Sánchez Arias, J. P. |
author_role |
author |
author2 |
Kanaan Neto, Antonio Nemer Córsico, Alejandro Hugo Kepler, Souza Oliveira Althaus, Leandro Gabriel Koester, Detlev Sánchez Arias, J. P. |
author2_role |
author author author author author author |
dc.contributor.author.fl_str_mv |
Corti, Mariela Alejandra Kanaan Neto, Antonio Nemer Córsico, Alejandro Hugo Kepler, Souza Oliveira Althaus, Leandro Gabriel Koester, Detlev Sánchez Arias, J. P. |
dc.subject.por.fl_str_mv |
Asterosismologia Fotometria estelar Pulsacoes estelares Anãs brancas Evolucao estelar Estrelas variaveis |
topic |
Asterosismologia Fotometria estelar Pulsacoes estelares Anãs brancas Evolucao estelar Estrelas variaveis White dwarfs Stars: individual: SDSSJ145847.02+070754.46 Stars: individual: SDSSJ173001.94+070600.25 Stars: low-mass |
dc.subject.eng.fl_str_mv |
White dwarfs Stars: individual: SDSSJ145847.02+070754.46 Stars: individual: SDSSJ173001.94+070600.25 Stars: low-mass |
description |
Context. The discovery of pulsations in low-mass stars opens an opportunity to probe their interiors and determine their evolution by employing the tools of asteroseismology. Aims. We aim to analyse high-speed photometry of SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25 and discover brightness variabilities. In order to locate these stars in the Te log g diagram, we fit optical spectra (SDSS) with synthetic nonmagnetic spectra derived from model atmospheres. Methods. To carry out this study, we used the photometric data we obtained for these stars with the 2.15 m telescope at CASLEO, Argentina. We analysed their light curves and applied the discrete Fourier transform (FT) to determine the pulsation frequencies. Finally, we compare both stars in the Te log g diagram, with two known pre-white dwarfs and seven pulsating pre-ELM white dwarf stars, Scuti, and SX Phe stars Results. We report the discovery of pulsations in SDSS J145847.02+070754.46 and SDSS J173001.94+070600.25. We determine their e ective temperature and surface gravity to be Te = 7972 200 K, log g = 4:25 0:5 and Te = 7925 200 K, log g = 4:25 0:5, respectively. With these parameters, these new pulsating low-mass stars can be identified with either ELM white dwarfs (with 0:17 M ) or more massive SX Phe stars. We identified pulsation periods of 3278.7 and 1633.9 s for SDSS J145847.02+070754.46 and a pulsation period of 3367.1 s for SDSS J173001.94+070600.25. These two new objects, together with those of Maxted et al. (2013, 2014), indicate the possible existence of a new instability domain towards the late stages of evolution of low-mass white dwarf stars, although their identification with SX Phe stars cannot be discarded. |
publishDate |
2016 |
dc.date.accessioned.fl_str_mv |
2016-12-07T02:26:39Z |
dc.date.issued.fl_str_mv |
2016 |
dc.type.driver.fl_str_mv |
Estrangeiro info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10183/150008 |
dc.identifier.issn.pt_BR.fl_str_mv |
0004-6361 |
dc.identifier.nrb.pt_BR.fl_str_mv |
001006140 |
identifier_str_mv |
0004-6361 001006140 |
url |
http://hdl.handle.net/10183/150008 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.ispartof.pt_BR.fl_str_mv |
Astronomy and astrophysics. Les Ulis. Vol. 587 (Mar. 2016), L5, 4 p. |
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openAccess |
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