Optical polarimetric observations of the microquasar LS 5039

We present the first optical polarimetric observations of the runaway microquasar LS 5039. Our results reveal the presence of a large amount (∼5%) of polarized emission towards this binary system. By combining polarimetric and spectroscopic observations of some stars in the field together with avail...

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Detalles Bibliográficos
Autores: Combi, Jorge Ariel, Cellone, Sergio Aldo, Martí, J., Ribó, M., Mirabel Miquele, Igor Félix, Casares, J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/84640
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/84640
Access Level:acceso abierto
Palabra clave:Ciencias Astronómicas
Binaries
Binaries - Stars
General - Polarization
Individual
LS 5039 - X-rays
Stars
Descripción
Sumario:We present the first optical polarimetric observations of the runaway microquasar LS 5039. Our results reveal the presence of a large amount (∼5%) of polarized emission towards this binary system. By combining polarimetric and spectroscopic observations of some stars in the field together with available statistical information on the galactic interstellar polarization of the region, we have estimated and subtracted the contribution of the interstellar polarization in this direction. As a result, we obtain an intrinsic polarization of ∼3% for the object, much higher than what would be expected from jet emission in the optical domain. We suggest that the polarized light originates by electron Thomson scattering in the stellar envelope of the companion star. This allows us to constrain the size of the region where the polarized emission originates, as well as estimating the scattering electronic density and the wind velocity at such distance.