AE Aurigae: First detection of non-thermal X-ray emission from a bow shock produced by a runaway star

Runaway stars produce shocks when passing through interstellar medium at supersonic velocities. Bow shocks have been detected in the mid-infrared for several high-mass runaway stars and in radio waves for one star. Theoretical models predict the production of high-energy photons by non-thermal radia...

Descripción completa

Detalles Bibliográficos
Autores: López Santiago, J., Miceli, M., Valle, María Victoria del, Romero, Gustavo Esteban, Bonito, R., Albacete Colombo, Juan Facundo, Pereira, V., De Castro, E., Damiani, F.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/84650
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/84650
Access Level:acceso abierto
Palabra clave:Ciencias Astronómicas
ISM: clouds
radiation mechanisms: non-thermal
stars: individual (AE Aur)
stars: kinematics and dynamics
stars: massive
X-rays: general
Descripción
Sumario:Runaway stars produce shocks when passing through interstellar medium at supersonic velocities. Bow shocks have been detected in the mid-infrared for several high-mass runaway stars and in radio waves for one star. Theoretical models predict the production of high-energy photons by non-thermal radiative processes in a number sufficiently large to be detected in X-rays. To date, no stellar bow shock has been detected at such energies. We present the first detection of X-ray emission from a bow shock produced by a runaway star. The star is AE Aur, which was likely expelled from its birthplace due to the encounter of two massive binary systems and now is passing through the dense nebula IC 405. The X-ray emission from the bow shock is detected at 30″ northeast of the star, coinciding with an enhancement in the density of the nebula. From the analysis of the observed X-ray spectrum of the source and our theoretical emission model, we confirm that the X-ray emission is produced mainly by inverse Compton upscattering of infrared photons from dust in the shock front.