Results 1 to 10 of about 85,552 (296)
On X‐Ray Variability in Active Binary Stars
Astrophysical Journal, 1999 We compare the count-rates of active binaries observed by Einstein and ROSAT. We find significant evidence for short-term variability (approx 0.32) and marginal evidence for a larger variability at longer timescales (approx 0.38). Modeling this excess as cyclic variability, we place an upper limit on the relative amplitude of the cyclic component ...
Vinay L Kashyap
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Soft X-Ray Variability of Binary X-Ray Stars
Astrophysical Journal, 1974 Richard McCray
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Spectral Energy Distributions of Southern Binary X-Ray Sources
The Astrophysical Journal Supplement Series, 2023 The rapid variability of X-ray binaries (XRBs) produces a wide range of X-ray states that are linked to activity across the electromagnetic spectrum. It is particularly challenging to study a sample of sources large enough to include all types in their ...
John M. Dickey +7 more
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An Optically Discovered Outburst from XTE J1859+226
The Astrophysical Journal, 2023 Using the Zwicky Transient Facility, in 2021 February we identified the first known outburst of the black hole X-ray transient XTE J1859+226 since its discovery in 1999. The outburst was visible at X-ray, UV, and optical wavelengths for less than 20 days,
Eric C. Bellm +15 more
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The X-ray emission of Be+stripped star binaries★
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT Using observations from Chandra, Swift, and XMM-Newton, we investigate the high-energy properties of all known (18) Be+sdO systems as well as seven additional Be binaries suspected to harbour stripped stars. The observed X-ray properties are found to be similar to those observed for other Be samples.
Nazé, Yaël +3 more
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Clumpy Wind Studies and the Nondetection of a Cyclotron Line in OAO 1657–415
The Astrophysical Journal, 2023 Winds of massive stars are suspected to be inhomogeneous (or clumpy), which biases the measures of their mass-loss rates. In high-mass X-ray binaries (HMXBs), the compact object can be used as an orbiting X-ray point source to probe the wind and ...
Pragati Pradhan +13 more
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The Astrophysical Journal, 2023 The launch of the Imaging X-ray Polarimetry Explorer (IXPE) on 2021 December 9 has opened a new window in X-ray astronomy. We report here the results of the first IXPE observation of a weakly magnetized neutron star, GS 1826−238, performed on 2022 March ...
Fiamma Capitanio +96 more
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The Binary X-Ray Stars – the Observational Picture [PDF]
Symposium - International Astronomical Union, 1975 When X-ray sources in the galaxy were discovered in 1962 (Giacconi et al., 1962) it was only possible to speculate on their nature, which centered on supernova and cosmic-ray phenomena since these were the only very energetic events known. In particular, the discovery of an X-ray source associated with the Crab Nebula led to the idea that the emission ...
Herbert Gursky, Ethan Schreier
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PSR J1953+1844 Probably Being the Descendant of an Ultracompact X-Ray Binary
The Astrophysical Journal Letters, 2023 PSR J1953+1844 (i.e., M71E) is a millisecond pulsar in a 53 minute binary orbit discovered by the Five-hundred-meter Aperture Spherical radio Telescope. The mass function from pulsar timing is 2.3 × 10 ^−7 M _⊙ .
Z. L. Yang +3 more
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Ultracompact X-ray binaries with He star companions [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT Ultracompact X-ray binaries (UCXBs) are low-mass X-ray binaries with hydrogen-deficient mass donors and ultrashort orbital periods. They have been suggested to be the potential Laser Interferometer Space Antenna (LISA) sources in the low-frequency region. Several channels for the formation of UCXBs have been proposed so far.
Bo Wang +7 more
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