Results 21 to 30 of about 52,966 (265)
The Radiation Transfer of Soft X-rays [PDF]
International Astronomical Union Colloquium, 1997 AbstractWe discuss the link between the halo plasma temperature and the power-law spectral index of the extragalactic background radiation. This link is of strong influence for the derivation of the Galactic halo intensity distribution. In principal, we can distinguish between two combinations of Galactic halo plasma temperature and power-law slope ...
Jürgen Kerp, Jochen Pietz
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Two-chicane compressed harmonic generation of soft x rays
Physical Review Special Topics. Accelerators and Beams, 2011 Seeding an electron bunch prior to compression simultaneously shifts the laser modulation to shorter wavelengths while decreasing the required modulation amplitude. The final x-ray wavelength is then tunable by controlling the compression factor with the
Daniel Ratner, Alex Chao, Zhirong Huang
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New Journal of Physics, 2012 We demonstrate an x-ray imaging method that combines Fourier transform holography with tomography (‘tomoholography’) for three-dimensional (3D) microscopic imaging. A 3D image of a diatom shell with a spatial resolution of 140 nm is presented. The experiment is realized by using a small gold sphere as the reference wave source for holographic imaging ...
Guehrs, E. +9 more
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On the soft X‐ray emission of M82 [PDF]
Astronomische Nachrichten, 2012 AbstractWe present a spatial analysis of the soft X‐ray and Hα emissions from the outflow of the starburst galaxy M82. We find that the two emissions are tightly correlated on various scales. The O VII triplet of M82, as resolved by X‐ray grating observations of XMM‐Newton, is dominated by the forbidden line, inconsistent with the thermal prediction ...
Liu, J., Wang, Q. D., Mao, S.
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Probing nucleobase photoprotection with soft x-rays
EPJ Web of Conferences, 2013 Nucleobases absorb strongly in the ultraviolet region, leading to molecular excitation into reactive states. The molecules avoid the photoreactions by funnelling the electronic energy into less reactive states on an ultrafast timescale via non-Born ...
Osipov T. +27 more
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Soft X-ray Lensless Imaging in Reflection Mode
Photonics, 2021 We report on the development and implementation of methodologies dedicated to soft X-ray imaging by coherent scattering in reflection mode. Two complementary approaches are tested, based on Fourier transform holography and on ptychography.
Horia Popescu +5 more
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Soft X-ray Emission of Quasars [PDF]
Symposium - International Astronomical Union, 1994 From a list of known quasars compiled from various catalogues we selected all sources detected by the PSPC (0.1 – 2.4 keV) aboard ROSAT with more than 80 counts during the all sky survey. A sample of 102 sources resulted. At higher redshifts most of the selected sources are radio-loud. At a redshift smaller than 0.50 we found 54 radio-quiet quasars and
N. Schartel, R. Walter, H. H. Fink
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A soft X-ray halo of the LMC? [PDF]
International Astronomical Union Colloquium, 1997 AbstractROSAT X-ray observations of the LMC show several X-ray shadows in the ¾ keV and 1.5 keV bands. The ¼ keV band is dominated by emission of the galactic foreground. It is uncertain whether there is additional soft X-ray contribution from the LMC.
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W/B short period multilayer structures for soft x-rays
AIP Advances, 2020 X-ray W/B multilayer mirrors with a period of 2.5 nm were deposited by dc magnetron sputtering and studied in comparison with W/Si multilayer systems of the same period.
R. V. Medvedev +4 more
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X-ray radiography of ageing Scots pine seeds.
Silva Fennica, 1980 Soft X-ray radiation (Grenz rays) has been used in the X-ray radiography of seeds. It is based on the principle that the different parts of the seed absorb X-rays to a slightly varying extent.
Ryynänen, Martti
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