6533b7cefe1ef96bd12570fa
RESEARCH PRODUCT
Long-term optical and X-ray variability of the Be/X-ray binary H 1145-619: Discovery of an ongoing retrograde density wave
Juan FabregatL. J. TownsendPablo ReigPablo ReigJulia Alfonso-garzonM. J. CoeCelia Sanchez-fernandezPeter KretschmarJari J. E. KajavaJari J. E. KajavaSteven M. CrawfordJ. M. Mas-hessesubject
BrightnessBe starAstrophysics::High Energy Astrophysical Phenomenamedia_common.quotation_subjectX-ray binarystars: emission-lineFOS: Physical sciencesAstrophysics01 natural sciencesSpectral lineDensity wave theoryPhotometry (optics)X-rays: binariesstars: neutrontechniques: photometric0103 physical sciencesAstrophysics::Solar and Stellar Astrophysics010303 astronomy & astrophysicsSolar and Stellar Astrophysics (astro-ph.SR)Astrophysics::Galaxy Astrophysicsmedia_commonHigh Energy Astrophysical Phenomena (astro-ph.HE)Physics010308 nuclear & particles physicsBeAstronomy and AstrophysicsLight curvestars: emission-line BeAstrophysics - Solar and Stellar Astrophysics13. Climate actionSpace and Planetary ScienceSkyAstrophysics::Earth and Planetary AstrophysicsAstrophysics - High Energy Astrophysical Phenomenatechniques: spectroscopicdescription
Multiwavelength monitoring of Be/X-ray binaries is crucial to understand the mechanisms producing their outbursts. H 1145-619 is one of these systems, which has recently displayed X-ray activity. We investigate the correlation between the optical emission and the X-ray activity to predict the occurrence of new X-ray outbursts from the inferred state of the circumstellar disc. We have performed a multiwavelength study of H 1145-619 from 1973 to 2017 and present here a global analysis of its variability over the last 40 years. We have used optical spectra from the SAAO, SMARTS and SALT telescopes and optical photometry from INTEGRAL/OMC and ASAS. We also used X-ray observations from INTEGRAL/JEM-X, and IBIS to generate the light curves and combined them with Swift/XRT to extract the X-ray spectra. In addition, we have compiled archival observations and measurements from the literature to complement these data. Comparing the evolution of the optical continuum emission with the Halpha line variability, we have identified three different patterns of optical variability: Global increases and decreases of the optical brightness (observed from 1982 to 1994 and from 2009 to 2017) that can be explained by the dissipation and replenishment of the circumstellar disc, superorbital variations with a period of Psuperorb~590 days (observed in 2002-2009) which seems to be related with the circumstellar disc, and optical outbursts (observed in 1998-1999 and 2002-2005) that we interpret as mass ejections. We have discovered the presence of a retrograde one-armed density wave, which appeared in 2016 and is still present in the circumstellar disc. We have carried out the most complete long-term optical study of the Be/X-ray binary H 1145-619 in correlation with its X-ray activity. We found for the fist time the presence of a retrograde density perturbation in the circumstellar disc of a Be/X-ray binary.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2017-01-01 | Astronomy & Astrophysics |