Observations of the 599 Hz Accreting X-Ray Pulsar IGR J00291+5934 during the 2004 Outburst and in Quiescence

Torres, M. A. P.; Jonker, P. G.; Steeghs, D.; Roelofs, G. H. A.; Bloom, J. S.; Casares, J.; Falco, E. E.; Garcia, M. R.; Marsh, T. R.; Mendez, M.; Miller, J. M.; Nelemans, G.; Rodríguez-Gil, P.
Referencia bibliográfica

The Astrophysical Journal, Volume 672, Issue 2, pp. 1079-1090.

Fecha de publicación:
1
2008
Número de autores
13
Número de autores del IAC
2
Número de citas
45
Número de citas referidas
35
Descripción
We report on optical and near-infrared observations obtained during and after the 2004 December discovery outburst of the X-ray transient and accretion-powered millisecond pulsar IGR J00291+5934. Our observations monitored the evolution of the brightness and the spectral properties of IGR J00291+5934 during the outburst decay toward quiescence. We also present optical, near-infrared, and Chandra observations obtained during true quiescence. Photometry of the field during outburst reveals an optical and near-infrared counterpart that brightened from R~=23 to R~=17 and from K=19 to K~=16. Spectral analysis of the RIJHK broadband photometry shows excess in the near-infrared bands that may be due to synchrotron emission. The Hα emission line profile suggests the orbital inclination is ~=22°-32°. The preferred range for the reddening toward the source is 0.7<=E(B-V)<=0.9, which is equivalent to 4.06×1021 cm-2<=NH<=5.22×1021 cm-2. The Chandra observations of the pulsar in its quiescent state gave an unabsorbed 0.5-10 keV flux for the best-fitting power-law model to the source spectrum of (7.0+/-0.9)×10-14 ergs cm-2 s-1 (adopting a hydrogen column of 4.6×1021 cm-2). The fit resulted in a power-law photon index of 2.4+0.5-0.4. The (R-K)0 color observed during quiescence supports an irradiated donor star and accretion disk. We estimate a distance of 2-4 kpc toward IGR J00291+5934 by using the outburst X-ray light curve and the estimated critical X-ray luminosity necessary to keep the outer parts of the accretion disk ionized. Using the quiescent X-ray luminosity and the spin period, we constrain the magnetic field of the neutron star to be <3×108 G.
Proyectos relacionados
Representación de la variable cataclísmica SS Cygni (Chris Moran)
Estrellas Binarias

El estudio de las estrellas binarias es una parte esencial de la astrofísica estelar. Una gran parte de las estrellas de nuestra Galaxia y de otras galaxias se ha formado en sistemas binarios o múltiples, por lo que entender la estructura y evolución de estos sistemas es importante desde el punto de vista estelar y galáctico. Un aspecto en el que

Pablo
Rodríguez Gil
Agujero negro en erupción
Agujeros negros, estrellas de neutrones, enanas blancas y su entorno local

Los agujeros negros y estrellas de neutrones en binarias de rayos-X son laboratorios únicos para explorar la física de estos objetos compactos. No solo permiten confirmar la existencia de agujeros negros de origen estelar a través de mediciones dinámicas de sus masas, sino que también permiten investigar el comportamiento de la materia y la

Montserrat
Armas Padilla