Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039

Gamma-ray binaries allow us to study physical processes such as particle acceleration up to TeV energies and VHE gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce outflows of radio-emitting particles whose structure can be imaged wi...

Descripción completa

Detalles Bibliográficos
Autores: Moldón Vara, Francisco Javier, Ribó Gomis, Marc, Paredes i Poy, Josep Maria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/151161
Acceso en línea:https://hdl.handle.net/2445/151161
Access Level:acceso abierto
Palabra clave:Astronomia de raigs gamma
Estels binaris de raigs X
Observacions astronòmiques
Gamma ray astronomy
X-ray binaries
Astronomical observations
id ES_83cd6f9f4fbc5fdf9b25db60fe782848
oai_identifier_str oai:diposit.ub.edu:2445/151161
network_acronym_str ES
network_name_str España
repository_id_str
spelling Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039Moldón Vara, Francisco JavierRibó Gomis, MarcParedes i Poy, Josep MariaAstronomia de raigs gammaEstels binaris de raigs XObservacions astronòmiquesGamma ray astronomyX-ray binariesAstronomical observationsGamma-ray binaries allow us to study physical processes such as particle acceleration up to TeV energies and VHE gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce outflows of radio-emitting particles whose structure can be imaged with VLBI. LS 5039 is a gamma-ray binary that has shown variable VLBI structures in the past. We aim to characterise the radio morphological changes of LS 5039 and discriminate if they are either repeatable or erratic. We observed LS 5039 with the VLBA at 5 GHz during five consecutive days to cover the 3.9-day orbit and an extra day to disentangle between orbital or secular variability. We also compiled the available high-resolution radio observations of the source to study its morphological variability at different orbital phases. We used a simple model to interpret the obtained images. The new observations show that the morphology of LS 5039 up to projected distances of 10 milliarcseconds changes in 24 h. The observed radio morphological changes display a periodic orbital modulation. Multifrequency and multiepoch VLBI observations confirm that the morphological periodicity is stable on timescales of years. Using a simple model we show that the observed behaviour is compatible with the presence of a young non-accreting pulsar with an outflow behind it. The morphology is reproduced for inclinations of the orbit of 60-75 deg. For masses of the companion star in the range 20-50 Msun, this range of inclinations implies a mass of the compact object of 1.3-2.7 Msun. The periodic orbital modulation of the radio morphology of LS 5039 suggests that all gamma-ray binaries are expected to show a similar behaviour. The changes in the radio structure of LS 5039 are compatible with the presence of a young non-accreting neutron star, which suggests that the known gamma-ray binaries contain young pulsars.EDP Sciences2012info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://hdl.handle.net/2445/151161Articles publicats en revistes (Física Quàntica i Astrofísica)reponame:Dipòsit Digital de la UBinstname:Universidad de BarcelonaInglésReproducció del document publicat a: https://doi.org/10.1051/0004-6361/201219553Astronomy & Astrophysics, 2012, vol. 548, num. A103https://doi.org/10.1051/0004-6361/201219553(c) The European Southern Observatory (ESO), 2012info:eu-repo/semantics/openAccessoai:diposit.ub.edu:2445/1511612026-05-27T06:46:51Z
dc.title.none.fl_str_mv Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
title Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
spellingShingle Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
Moldón Vara, Francisco Javier
Astronomia de raigs gamma
Estels binaris de raigs X
Observacions astronòmiques
Gamma ray astronomy
X-ray binaries
Astronomical observations
title_short Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
title_full Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
title_fullStr Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
title_full_unstemmed Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
title_sort Periodic morphological changes in the radio structure of the gamma-ray binary LS 5039
dc.creator.none.fl_str_mv Moldón Vara, Francisco Javier
Ribó Gomis, Marc
Paredes i Poy, Josep Maria
author Moldón Vara, Francisco Javier
author_facet Moldón Vara, Francisco Javier
Ribó Gomis, Marc
Paredes i Poy, Josep Maria
author_role author
author2 Ribó Gomis, Marc
Paredes i Poy, Josep Maria
author2_role author
author
dc.subject.none.fl_str_mv Astronomia de raigs gamma
Estels binaris de raigs X
Observacions astronòmiques
Gamma ray astronomy
X-ray binaries
Astronomical observations
topic Astronomia de raigs gamma
Estels binaris de raigs X
Observacions astronòmiques
Gamma ray astronomy
X-ray binaries
Astronomical observations
description Gamma-ray binaries allow us to study physical processes such as particle acceleration up to TeV energies and VHE gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce outflows of radio-emitting particles whose structure can be imaged with VLBI. LS 5039 is a gamma-ray binary that has shown variable VLBI structures in the past. We aim to characterise the radio morphological changes of LS 5039 and discriminate if they are either repeatable or erratic. We observed LS 5039 with the VLBA at 5 GHz during five consecutive days to cover the 3.9-day orbit and an extra day to disentangle between orbital or secular variability. We also compiled the available high-resolution radio observations of the source to study its morphological variability at different orbital phases. We used a simple model to interpret the obtained images. The new observations show that the morphology of LS 5039 up to projected distances of 10 milliarcseconds changes in 24 h. The observed radio morphological changes display a periodic orbital modulation. Multifrequency and multiepoch VLBI observations confirm that the morphological periodicity is stable on timescales of years. Using a simple model we show that the observed behaviour is compatible with the presence of a young non-accreting pulsar with an outflow behind it. The morphology is reproduced for inclinations of the orbit of 60-75 deg. For masses of the companion star in the range 20-50 Msun, this range of inclinations implies a mass of the compact object of 1.3-2.7 Msun. The periodic orbital modulation of the radio morphology of LS 5039 suggests that all gamma-ray binaries are expected to show a similar behaviour. The changes in the radio structure of LS 5039 are compatible with the presence of a young non-accreting neutron star, which suggests that the known gamma-ray binaries contain young pulsars.
publishDate 2012
dc.date.none.fl_str_mv 2012
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv https://hdl.handle.net/2445/151161
url https://hdl.handle.net/2445/151161
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.relation.none.fl_str_mv Reproducció del document publicat a: https://doi.org/10.1051/0004-6361/201219553
Astronomy & Astrophysics, 2012, vol. 548, num. A103
https://doi.org/10.1051/0004-6361/201219553
dc.rights.none.fl_str_mv (c) The European Southern Observatory (ESO), 2012
info:eu-repo/semantics/openAccess
rights_invalid_str_mv (c) The European Southern Observatory (ESO), 2012
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 Articles publicats en revistes (Física Quàntica i Astrofísica)
reponame:Dipòsit Digital de la UB
instname:Universidad de Barcelona
instname_str Universidad de Barcelona
reponame_str Dipòsit Digital de la UB
collection Dipòsit Digital de la UB
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869412162538045440
score 15,300724

Similares en LA Referencia