Results 11 to 20 of about 1,203,775 (345)

X-RAY MONITORING OF ULTRALUMINOUS X-RAY SOURCES [PDF]

The Astrophysical Journal, 2009
X-ray monitoring observations were performed with the Swift observatory of the ultraluminous X-ray sources Holmberg IX X-1, NGC 5408 X-1, and NGC 4395 X-2 and also of the nuclear X-ray source in NGC 4395. Holmberg IX X-1 remains in the hard X-ray spectral state as its flux varies by a factor of 7 up to an (isotropic) luminosity of 2.8E40 erg/s.
Kaaret, Philip, Feng, Hua
openaire   +2 more sources

X-Ray Burst Sources [PDF]

Monthly Notices of the Royal Astronomical Society, 1977
Since those reviews there have been very important new developments. First, a surprisingly new animal, GRO J1744—28 (better known as the Bursting Pulsar), made its debut in 1995. Second, but NOT last, in 1996/97 kHz pulsations were discovered in the persistent emission of several burst sources, and near coherent pulsations were detected in type I X-ray
openaire   +3 more sources

Two-way tuning of structural order in metallic glasses

Nature Communications, 2020
While metallic glasses are expected to have tunable structures, these have rarely been demonstrated. Here, the authors combine temperature and pressure to show a two-way structural tuning in rare earth-based metallic glasses beyond the nearest-neighbor ...
Hongbo Lou, Zhidan Zeng, Fei Zhang, Songyi Chen, Peng Luo, Xiehang Chen, Yang Ren, Vitali B. Prakapenka, Clemens Prescher, Xiaobing Zuo, Tao Li, Jianguo Wen, Wei-Hua Wang, Hongwei Sheng, Qiaoshi Zeng   +14 more
doaj   +1 more source

Extragalactic X-ray Sources [PDF]

Symposium - International Astronomical Union, 1973
A review is given of the physical properties of extragalactic X-ray sources. The generation of X-rays as thermal bremsstrahlung, by the synchrotron mechanism or by Compton Scattering, is discussed. It is shown that each may be important depending on the circumstances.
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The novel high-pressure/high-temperature compound Co12P7 determined from synchrotron data

Acta Crystallographica Section E: Crystallographic Communications, 2020
The structural properties of cobalt phosphides were investigated at high pressures and temperatures to better understand the behavior of metal-rich phosphides in Earth and planetary interiors. Using single-crystal X-ray diffraction synchrotron data and a
Claire Zurkowski, Barbara Lavina, Stella Chariton, Sergey Tkachev, Vitali Prakapenka, Andrew Campbell   +5 more
doaj   +1 more source

Local structure of liquid gallium under pressure

Scientific Reports, 2017
In situ high energy X-ray pair distribution function (PDF) measurements, microtomography and reverse Monte Carlo simulations were used to characterize the local structure of liquid gallium up to 1.9 GPa.
Renfeng Li, Luhong Wang, Liangliang Li, Tony Yu, Haiyan Zhao, Karena W. Chapman, Yanbin Wang, Mark L. Rivers, Peter J. Chupas, Ho-kwang Mao, Haozhe Liu   +10 more
doaj   +1 more source

Ultraluminous X-ray Sources [PDF]

Proceedings of Accretion Processes in Cosmic Sources – II — PoS(APCS2018), 2019
Ultraluminous X-ray sources (ULXs) represent a class of binary systems that are more luminous than any black hole in our Galaxy. The nature of these objects remained unclear for a long time. The most popular models for the ULXs involve either intermediate mass black holes (IMBHs) or stellar-mass black holes accreting at super-Eddington rates.
openaire   +2 more sources

Near-Infrared Counterparts to Chandra X-ray Sources toward the Galactic Center. I. Statistics and a Catalog of Candidates [PDF]

, 2009
We present a catalog of 5184 candidate infrared counterparts to X-ray sources detected towards the Galactic center. The X-ray sample contains 9017 point sources detected in this region by the Chandra X-ray Observatory, including data from a recent deep ...
Bauer, Franz E., Mauerhan, Jon C., Morris, Mark R., Muno, Michael P., Nagata, Tetsuya, Nishiyama, Shogo   +5 more
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SPICES II. Optical and Near-Infrared Identifications of Faint X-Ray Sources from Deep Chandra Observations of Lynx [PDF]

, 2002
We present our first results on field X-ray sources detected in a deep, 184.7 ks observation with the ACIS-I camera on Chandra. The observations target the Lynx field of SPICES, and contains three known X-ray-emitting clusters out to z=1.27.
Chaffee, Frederic H., Connolly, Andrew, Dawson, Steve, Dey, Arjun, Eisenhardt, Peter, Elston, Richard, Holden, Brad, Rosati, Piero, Spinrad, Hyron, Stanford, S. A., Stern, Daniel, Tozzi, Paolo, Wu, K. L.   +12 more
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Altered chemistry of oxygen and iron under deep Earth conditions

Nature Communications, 2019
Iron oxides prevail in the deep Earth, at extreme pressures and temperatures, with different stoichiometries than in ambient conditions. Here, high-pressure synchrotron X-ray spectroscopic measurements reveal the oxidation states of Fe and O in iron ...
Jin Liu, Qingyang Hu, Wenli Bi, Liuxiang Yang, Yuming Xiao, Paul Chow, Yue Meng, Vitali B. Prakapenka, Ho-Kwang Mao, Wendy L. Mao   +9 more
doaj   +1 more source