Results 11 to 20 of about 14,620 (167)
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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A possible nonthermal X-ray emission from γ Cas analogues stars
Open Astronomy, 2021 We analyze the archival XMM-Newton X-ray observations of 15 γ Cas analogue stars and two candidates for such objects. The EPIC spectra of the considered stars in the range of 0.2-8 keV were extracted and fitted by different models.
Ryspaeva Elizaveta B. +1 more
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The Astrophysical Journal Supplement Series, 2023 The young massive OB association Cygnus OB2, in the Cygnus X complex, is the closest (∼1400 pc) star-forming region to the Sun hosting thousands of young low-mass stars and up to 1000 OB stars, among which are some of the most massive stars known in our ...
M. G. Guarcello +6 more
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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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X-Ray Bursting Neutron Stars [PDF]
Symposium - International Astronomical Union, 1987 The maximum peak luminosity of the X-ray bursts from a burster is most likely interpreted as the Eddington luminosity of a helium-rich envelope surrounding a neutron star. If this interpretation is true, we can obtain a relation between the mass and the radius of the neutron star in terms of the maximum effective temperature of bursts.
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Symbiotic stars in X-rays [PDF]
Astronomy & Astrophysics, 2013 Due to space restrictions, the full abstract can be seen in the PDF version.
Luna, Gerardo Juan Manuel +3 more
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X-Ray Observations of Symbiotic Stars [PDF]
International Astronomical Union Colloquium, 1981 AbstractObservations are reported of 19 symbiotic stars made with the imaging proportional counter of the Einstein Observatory. Three of the objects (HM Sge, V 1016 Cyg and RR Tel) were detected as soft X-ray sources. All three have shown slow-nova eruptions in the past 40 years.
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X-Ray Observations of Be Stars [PDF]
Symposium - International Astronomical Union, 1982 Be star binaries with neutron star companions are shown to constitute a major class of X-ray sources. Some general observational and interpretive techniques of X-ray astronomy are reviewed. Data for 12 Be/X-ray binary systems are summarized. The Be/X-ray binaries are found to be systematically wider systems, with lower-mass primaries, and with ...
Saul Rappaport +1 more
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News on the X-ray emission from hot subdwarf stars
Open Astronomy, 2017 In latest years, the high sensitivity of the instruments on-board the XMM-Newton and Chandra satellites allowed us to explore the properties of the X-ray emission from hot subdwarf stars.
Palombara Nicola La, Mereghetti Sandro
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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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