Symbiotic stars in X-rays
Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of nine white dwarf symbiotics that were not previously known to be X-ray...
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todo:paper_00046361_v559_n_p_Luna2023-10-03T14:00:47Z Symbiotic stars in X-rays Luna, G.J.M. Sokoloski, J.L. Mukai, K. Nelson, T. Accretion, accretion disks Binaries: symbiotic X-rays: binaries Accretion , accretion disks Binaries: symbiotic Brightness variations Classification scheme Hard x-ray emission Physical interpretation Spectral components X-rays: Binaries Accretion Accretion disks Binaries: symbiotic Brightness variations Classification scheme Physical interpretation Spectral components X-rays: Binaries Electromagnetic wave emission Electron sources Flickering Stars Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs Bins Boundary layers Electromagnetic wave emission Electron sources Flickering Giant stars Mass transfer Stars Stochastic systems Supernovae Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs X rays White dwarfs Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of nine white dwarf symbiotics that were not previously known to be X-ray sources and one that had previously been detected as a supersoft X-ray source. The nine new X-ray detections were the result of a survey of 41 symbiotic stars, and they increase the number of symbiotic stars known to be X-ray sources by approximately 30%. The Swift/XRT telescope detected all of the new X-ray sources at energies greater than 2 keV. Their X-ray spectra are consistent with thermal emission and fall naturally into three distinct groups. The first group contains those sources with a single, highly absorbed hard component that we identify as probably coming from an accretion-disk boundary layer. The second group is composed of those sources with a single, soft X-ray spectral component that probably originates in a region where low-velocity shocks produce X-ray emission, i.e., a colliding-wind region. The third group consists of those sources with both hard and soft X-ray spectral components. We also find that unlike in the optical, where rapid, stochastic brightness variations from the accretion disk typically are not seen, detectable UV flickering is a common property of symbiotic stars. Supporting our physical interpretation of the two X-ray spectral components, simultaneous Swift UV photometry shows that symbiotic stars with harder X-ray emission tend to have stronger UV flickering, which is usually associated with accretion through a disk. To place these new observations in the context of previous work on X-ray emission from symbiotic stars, we modified and extended the α/β/γ classification scheme for symbiotic-star X-ray spectra that was introduced by Muerset et al. based upon observations with the ROSAT satellite, to include a new δ classification for sources with hard X-ray emission from the innermost accretion region. Because we have identified the elusive accretion component in the emission from a sample of symbiotic stars, our results have implications for the understanding of wind-fed mass transfer in wide binaries, and the accretion rate in one class of candidate progenitors of type Ia supernovae. © 2013 ESO. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00046361_v559_n_p_Luna |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Accretion, accretion disks Binaries: symbiotic X-rays: binaries Accretion , accretion disks Binaries: symbiotic Brightness variations Classification scheme Hard x-ray emission Physical interpretation Spectral components X-rays: Binaries Accretion Accretion disks Binaries: symbiotic Brightness variations Classification scheme Physical interpretation Spectral components X-rays: Binaries Electromagnetic wave emission Electron sources Flickering Stars Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs Bins Boundary layers Electromagnetic wave emission Electron sources Flickering Giant stars Mass transfer Stars Stochastic systems Supernovae Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs X rays White dwarfs |
| spellingShingle |
Accretion, accretion disks Binaries: symbiotic X-rays: binaries Accretion , accretion disks Binaries: symbiotic Brightness variations Classification scheme Hard x-ray emission Physical interpretation Spectral components X-rays: Binaries Accretion Accretion disks Binaries: symbiotic Brightness variations Classification scheme Physical interpretation Spectral components X-rays: Binaries Electromagnetic wave emission Electron sources Flickering Stars Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs Bins Boundary layers Electromagnetic wave emission Electron sources Flickering Giant stars Mass transfer Stars Stochastic systems Supernovae Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs X rays White dwarfs Luna, G.J.M. Sokoloski, J.L. Mukai, K. Nelson, T. Symbiotic stars in X-rays |
| topic_facet |
Accretion, accretion disks Binaries: symbiotic X-rays: binaries Accretion , accretion disks Binaries: symbiotic Brightness variations Classification scheme Hard x-ray emission Physical interpretation Spectral components X-rays: Binaries Accretion Accretion disks Binaries: symbiotic Brightness variations Classification scheme Physical interpretation Spectral components X-rays: Binaries Electromagnetic wave emission Electron sources Flickering Stars Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs Bins Boundary layers Electromagnetic wave emission Electron sources Flickering Giant stars Mass transfer Stars Stochastic systems Supernovae Telescopes X ray analysis X ray apparatus X ray optics X ray scattering X ray spectrographs X rays White dwarfs |
| description |
Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of nine white dwarf symbiotics that were not previously known to be X-ray sources and one that had previously been detected as a supersoft X-ray source. The nine new X-ray detections were the result of a survey of 41 symbiotic stars, and they increase the number of symbiotic stars known to be X-ray sources by approximately 30%. The Swift/XRT telescope detected all of the new X-ray sources at energies greater than 2 keV. Their X-ray spectra are consistent with thermal emission and fall naturally into three distinct groups. The first group contains those sources with a single, highly absorbed hard component that we identify as probably coming from an accretion-disk boundary layer. The second group is composed of those sources with a single, soft X-ray spectral component that probably originates in a region where low-velocity shocks produce X-ray emission, i.e., a colliding-wind region. The third group consists of those sources with both hard and soft X-ray spectral components. We also find that unlike in the optical, where rapid, stochastic brightness variations from the accretion disk typically are not seen, detectable UV flickering is a common property of symbiotic stars. Supporting our physical interpretation of the two X-ray spectral components, simultaneous Swift UV photometry shows that symbiotic stars with harder X-ray emission tend to have stronger UV flickering, which is usually associated with accretion through a disk. To place these new observations in the context of previous work on X-ray emission from symbiotic stars, we modified and extended the α/β/γ classification scheme for symbiotic-star X-ray spectra that was introduced by Muerset et al. based upon observations with the ROSAT satellite, to include a new δ classification for sources with hard X-ray emission from the innermost accretion region. Because we have identified the elusive accretion component in the emission from a sample of symbiotic stars, our results have implications for the understanding of wind-fed mass transfer in wide binaries, and the accretion rate in one class of candidate progenitors of type Ia supernovae. © 2013 ESO. |
| format |
JOUR |
| author |
Luna, G.J.M. Sokoloski, J.L. Mukai, K. Nelson, T. |
| author_facet |
Luna, G.J.M. Sokoloski, J.L. Mukai, K. Nelson, T. |
| author_sort |
Luna, G.J.M. |
| title |
Symbiotic stars in X-rays |
| title_short |
Symbiotic stars in X-rays |
| title_full |
Symbiotic stars in X-rays |
| title_fullStr |
Symbiotic stars in X-rays |
| title_full_unstemmed |
Symbiotic stars in X-rays |
| title_sort |
symbiotic stars in x-rays |
| url |
http://hdl.handle.net/20.500.12110/paper_00046361_v559_n_p_Luna |
| work_keys_str_mv |
AT lunagjm symbioticstarsinxrays AT sokoloskijl symbioticstarsinxrays AT mukaik symbioticstarsinxrays AT nelsont symbioticstarsinxrays |
| _version_ |
1782029827942907904 |