Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle
- Autores
- Ibañez Bustos, Romina Valeria; Buccino, Andrea Paola; Messina, S.; Lanza, A. F.; Mauas, Pablo Jacobo David
- Año de publicación
- 2020
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Aims. Recently, new debates about the role of layers of strong shear have emerged in stellar dynamo theory. Further information on the long-term magnetic activity of fully convective stars could help determine whether their underlying dynamo could sustain activity cycles similar to the solar one. Methods. We performed a thorough study of the short- and long-term magnetic activity of the young active dM4 star Gl 729. First, we analyzed long-cadence K2 photometry to characterize its transient events (e.g., flares) and global and surface differential rotation. Then, from the Mount Wilson S-indexes derived from CASLEO spectra and other public observations, we analyzed its long-term activity between 1998 and 2020 with four different time-domain techniques to detect cyclic patterns. Finally, we explored the chromospheric activity at different heights with simultaneous measurements of the Hα and the Na I D indexes, and we analyzed their relations with the S-Index. Results. We found that the cumulative flare frequency follows a power-law distribution with slope ~-0.73 for the range 1032-1034 erg. We obtained Prot = (2.848 ± 0.001) days, and we found no evidence of differential rotation. We also found that this young active star presents a long-term activity cycle with a length of about 4 yr; there is less significant evidence of a shorter cycle of 0.8 yr. The star also shows a broad activity minimum between 1998 and 2004. We found a correlation between the S index, on the one hand, and the Hα the Na I D indexes, on the other hand, although the saturation level of these last two indexes is not observed in the Ca lines. Conclusions. Because the maximum-entropy spot model does not reflect migration between active longitudes, this activity cycle cannot be explained by a solar-type dynamo. It is probably caused by an α2-dynamo.
Fil: Ibañez Bustos, Romina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina
Fil: Buccino, Andrea Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina
Fil: Messina, S.. Osservatorio Astrofisico di Catania; Italia
Fil: Lanza, A. F.. Osservatorio Astrofisico di Catania; Italia
Fil: Mauas, Pablo Jacobo David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina - Materia
-
STARS: ACTIVITY
STARS: LATE-TYPE
TECHNIQUES: SPECTROSCOPIC - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/162555
Ver los metadatos del registro completo
id |
CONICETDig_afdf2e67d65cf87ba98e91f4561635f5 |
---|---|
oai_identifier_str |
oai:ri.conicet.gov.ar:11336/162555 |
network_acronym_str |
CONICETDig |
repository_id_str |
3498 |
network_name_str |
CONICET Digital (CONICET) |
spelling |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycleIbañez Bustos, Romina ValeriaBuccino, Andrea PaolaMessina, S.Lanza, A. F.Mauas, Pablo Jacobo DavidSTARS: ACTIVITYSTARS: LATE-TYPETECHNIQUES: SPECTROSCOPIChttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1Aims. Recently, new debates about the role of layers of strong shear have emerged in stellar dynamo theory. Further information on the long-term magnetic activity of fully convective stars could help determine whether their underlying dynamo could sustain activity cycles similar to the solar one. Methods. We performed a thorough study of the short- and long-term magnetic activity of the young active dM4 star Gl 729. First, we analyzed long-cadence K2 photometry to characterize its transient events (e.g., flares) and global and surface differential rotation. Then, from the Mount Wilson S-indexes derived from CASLEO spectra and other public observations, we analyzed its long-term activity between 1998 and 2020 with four different time-domain techniques to detect cyclic patterns. Finally, we explored the chromospheric activity at different heights with simultaneous measurements of the Hα and the Na I D indexes, and we analyzed their relations with the S-Index. Results. We found that the cumulative flare frequency follows a power-law distribution with slope ~-0.73 for the range 1032-1034 erg. We obtained Prot = (2.848 ± 0.001) days, and we found no evidence of differential rotation. We also found that this young active star presents a long-term activity cycle with a length of about 4 yr; there is less significant evidence of a shorter cycle of 0.8 yr. The star also shows a broad activity minimum between 1998 and 2004. We found a correlation between the S index, on the one hand, and the Hα the Na I D indexes, on the other hand, although the saturation level of these last two indexes is not observed in the Ca lines. Conclusions. Because the maximum-entropy spot model does not reflect migration between active longitudes, this activity cycle cannot be explained by a solar-type dynamo. It is probably caused by an α2-dynamo.Fil: Ibañez Bustos, Romina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Buccino, Andrea Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Messina, S.. Osservatorio Astrofisico di Catania; ItaliaFil: Lanza, A. F.. Osservatorio Astrofisico di Catania; ItaliaFil: Mauas, Pablo Jacobo David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaEDP Sciences2020-11info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/162555Ibañez Bustos, Romina Valeria; Buccino, Andrea Paola; Messina, S.; Lanza, A. F.; Mauas, Pablo Jacobo David; Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle; EDP Sciences; Astronomy and Astrophysics; 644; 11-2020; 1-140004-6361CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/10.1051/0004-6361/202039164info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/202039164info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:01:57Zoai:ri.conicet.gov.ar:11336/162555instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:01:57.71CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
title |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
spellingShingle |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle Ibañez Bustos, Romina Valeria STARS: ACTIVITY STARS: LATE-TYPE TECHNIQUES: SPECTROSCOPIC |
title_short |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
title_full |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
title_fullStr |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
title_full_unstemmed |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
title_sort |
Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle |
dc.creator.none.fl_str_mv |
Ibañez Bustos, Romina Valeria Buccino, Andrea Paola Messina, S. Lanza, A. F. Mauas, Pablo Jacobo David |
author |
Ibañez Bustos, Romina Valeria |
author_facet |
Ibañez Bustos, Romina Valeria Buccino, Andrea Paola Messina, S. Lanza, A. F. Mauas, Pablo Jacobo David |
author_role |
author |
author2 |
Buccino, Andrea Paola Messina, S. Lanza, A. F. Mauas, Pablo Jacobo David |
author2_role |
author author author author |
dc.subject.none.fl_str_mv |
STARS: ACTIVITY STARS: LATE-TYPE TECHNIQUES: SPECTROSCOPIC |
topic |
STARS: ACTIVITY STARS: LATE-TYPE TECHNIQUES: SPECTROSCOPIC |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
Aims. Recently, new debates about the role of layers of strong shear have emerged in stellar dynamo theory. Further information on the long-term magnetic activity of fully convective stars could help determine whether their underlying dynamo could sustain activity cycles similar to the solar one. Methods. We performed a thorough study of the short- and long-term magnetic activity of the young active dM4 star Gl 729. First, we analyzed long-cadence K2 photometry to characterize its transient events (e.g., flares) and global and surface differential rotation. Then, from the Mount Wilson S-indexes derived from CASLEO spectra and other public observations, we analyzed its long-term activity between 1998 and 2020 with four different time-domain techniques to detect cyclic patterns. Finally, we explored the chromospheric activity at different heights with simultaneous measurements of the Hα and the Na I D indexes, and we analyzed their relations with the S-Index. Results. We found that the cumulative flare frequency follows a power-law distribution with slope ~-0.73 for the range 1032-1034 erg. We obtained Prot = (2.848 ± 0.001) days, and we found no evidence of differential rotation. We also found that this young active star presents a long-term activity cycle with a length of about 4 yr; there is less significant evidence of a shorter cycle of 0.8 yr. The star also shows a broad activity minimum between 1998 and 2004. We found a correlation between the S index, on the one hand, and the Hα the Na I D indexes, on the other hand, although the saturation level of these last two indexes is not observed in the Ca lines. Conclusions. Because the maximum-entropy spot model does not reflect migration between active longitudes, this activity cycle cannot be explained by a solar-type dynamo. It is probably caused by an α2-dynamo. Fil: Ibañez Bustos, Romina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: Buccino, Andrea Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: Messina, S.. Osservatorio Astrofisico di Catania; Italia Fil: Lanza, A. F.. Osservatorio Astrofisico di Catania; Italia Fil: Mauas, Pablo Jacobo David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina |
description |
Aims. Recently, new debates about the role of layers of strong shear have emerged in stellar dynamo theory. Further information on the long-term magnetic activity of fully convective stars could help determine whether their underlying dynamo could sustain activity cycles similar to the solar one. Methods. We performed a thorough study of the short- and long-term magnetic activity of the young active dM4 star Gl 729. First, we analyzed long-cadence K2 photometry to characterize its transient events (e.g., flares) and global and surface differential rotation. Then, from the Mount Wilson S-indexes derived from CASLEO spectra and other public observations, we analyzed its long-term activity between 1998 and 2020 with four different time-domain techniques to detect cyclic patterns. Finally, we explored the chromospheric activity at different heights with simultaneous measurements of the Hα and the Na I D indexes, and we analyzed their relations with the S-Index. Results. We found that the cumulative flare frequency follows a power-law distribution with slope ~-0.73 for the range 1032-1034 erg. We obtained Prot = (2.848 ± 0.001) days, and we found no evidence of differential rotation. We also found that this young active star presents a long-term activity cycle with a length of about 4 yr; there is less significant evidence of a shorter cycle of 0.8 yr. The star also shows a broad activity minimum between 1998 and 2004. We found a correlation between the S index, on the one hand, and the Hα the Na I D indexes, on the other hand, although the saturation level of these last two indexes is not observed in the Ca lines. Conclusions. Because the maximum-entropy spot model does not reflect migration between active longitudes, this activity cycle cannot be explained by a solar-type dynamo. It is probably caused by an α2-dynamo. |
publishDate |
2020 |
dc.date.none.fl_str_mv |
2020-11 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/162555 Ibañez Bustos, Romina Valeria; Buccino, Andrea Paola; Messina, S.; Lanza, A. F.; Mauas, Pablo Jacobo David; Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle; EDP Sciences; Astronomy and Astrophysics; 644; 11-2020; 1-14 0004-6361 CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/162555 |
identifier_str_mv |
Ibañez Bustos, Romina Valeria; Buccino, Andrea Paola; Messina, S.; Lanza, A. F.; Mauas, Pablo Jacobo David; Activity-rotation in the dM4 star Gl 729: A possible chromospheric cycle; EDP Sciences; Astronomy and Astrophysics; 644; 11-2020; 1-14 0004-6361 CONICET Digital CONICET |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/10.1051/0004-6361/202039164 info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/202039164 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
EDP Sciences |
publisher.none.fl_str_mv |
EDP Sciences |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
collection |
CONICET Digital (CONICET) |
instname_str |
Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.name.fl_str_mv |
CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
_version_ |
1844613818225786880 |
score |
13.070432 |