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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 22 for “"soft x-rays"”.
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Adaptive control of coherent soft X-rays
The availability of coherent soft x-rays through the nonlinear optical process of high-harmonic generation allows for the monitoring of the fastest events ever observed in the laboratory. The attosecond pulses produced are the fundamental tool for the time-resolved study of electron motion in …
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Effects of Solar Soft X-rays on Earth's Atmosphere
The soft x-rays (wavelengths less than 30 nm) emitted by the sun are responsible for the production of high energy photoelectrons in the D and E regions of the ionosphere, where they deposit most of their energy. The photoelectrons created by this process are the main drivers for dissociation of …
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Spatial and spectral comparisons of soft X-rays from galaxies of different morphological types
… of the complexity of the galaxy spectra and the softer energy band of ROSAT. In order to better characterise the soft X-ray emission from galaxies, we present seven high signal-to-noise composite spectra. Elliptical galaxies are separated into four groups according to their offset in X-ray …
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Establishment of the Physical and Technical Prerequisites for the Determination of the Relative Biological Effectiveness of Low-energy Monochromatic X-rays
Low-energy X-rays in the range 10 - 50 keV have a wide application. One important application in radiological diagnostics is mammography, whereas, in radiotherapy, they are used for irradiation of superficial tumours, in brachytherapy and photon activation therapy. The importance of soft X-rays for …
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Alcator C-Mod soft X-ray pulse height analysis system
… The PHA utilizes a Si(Li) detector to measure soft X-rays in the 1-30 keV range with an energy resolution on the order of 100eV. A FASTComtec MCA-3 multichannel analyzer allows integration times of ims while the PHA supports counting rates of up to 80kHz. The thermal electron temperature is …
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Struktūrinių intarpų kiekio safyro gardelėje temperatūrinė priklausomybė /
… using vacancies generation evoked by irradiated soft x-rays the development of the new producing technologies can be hoped. Appendixes contain the CD.
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Development and spatio-spectral mapping of a capillary high harmonic source
… system. Using this system a coherent beam of soft x-rays is generated, studied and applied. A series of experiments was then undertaken in order to deepen our knowledge of the HHG process and to optimise the performance of the source. Notable contributions made to the field are: A novel laser …
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Fotodestruição do benzeno em ambientes interestelares
… Synchrotron Light Laboratory (LNLS), using soft X-ray and UV photons. The experimental set-up consists of a high vacuum chamber with a Time-Of-Flight Mass Spectrometer (TOF-MS). Kinetic energy distributions, abundances for each ionic fragment and dissociative and non-dissociative …
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Polarized Radiative Transfer in the Magnetospheres and Atmospheres of Neutron Stars
… are sources of strongly polarized emission in X-rays or soft gamma-rays due to the presence of strong magnetic fields. Radiation transport of soft X-rays in neutron star surface layers is critical to the determination of the emergent anisotropy of light intensity and polarization signatures. …
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The binary system containing the pulsar PSR 1913+16 and ultra-violet and x-radiation from accreting magnetic white dwarfs
… component can be observable in hard X-rays, while the black-body component can be'observab1e in soft X-rays. The observed spectrum varies with time when the accretion rate does. Ordinarily, only a few percent of the total accretion luminosity is accessible to existing detectors. …
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A hybrid analysis approach to the high energy stereoscopic system phase II mono-analysis
… by incident high energy particles (gamma rays or cosmic rays) on the Earth's atmosphere. The array consists of four 107 m2 optical telescopes and a larger 614 m2 collective surface area telescope in the center of the array. The larger telescope has the ability of detecting showers induced …
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Low coronal signatures of coronal mass ejections: coronal “waves” and dimmings
… and potential counterparts in radio, H!, soft X-rays and He II wavelengths are also discussed. New observational constraints on EIT coronal waves are presented, most notably diffuse coronal waves are shown to have a magnetic nature. Finding that many observational constraints are not …
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Laser-Driven Particle Acceleration - Improving Performance Through Smart Target Design
… light onto the central axis. Short bursts of soft x-rays were produced inside capillaries. Finally, the use of an asymmetric laser field at the focus facilitated off-axis electron injection into the accelerating phase of a plasma wake oscillation and enhanced x-ray emission.
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Mergers of Supermassive Black Hole Binaries in Gas-rich Environments: Models of Event Rates and Electromagnetic Signatures
… remnant may exhibit a dramatic brightening of soft X-rays on timescales of several years. Our results suggest that this "afterglow" may become detectable more quickly after the merger than previously estimated. Third, we investigate whether these afterglow episodes could be observed …
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High-resolution detectors for soft X-ray spectroscopy
… Inelastic X-ray Scattering (RIXS) is a modern soft X-ray spectroscopy technique used to investigate the structure of and excitations in materials. It requires high resolution spectrometers and a brilliant, tunable, X-ray source and therefore is carried out at spectrometers such as SAXES at the …
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False Alarms in the Forecasting of Solar Energetic Particle Events
… speed, solar flares with high peak emission in soft X-rays, or a combination of the two. SEPs, however, are not detected following all fast CMEs or intense flares. Those large solar events, which might reasonably have been expected to produce SEPs at Earth but which failed to do so, may be …
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Fabrication of high-throughput critical-angle X-ray transmission gratings for wavelength-dispersive spectroscopy
… in the resolving power of future space-based, soft x-ray spectrometers. This will enhance further studies of the universe's make-up, such as the composition of the intergalactic medium, black holes, neutron stars and other high energy sources. Conceptually, x-rays are reflected in the device …
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Electron acceleration at localized wave structures in the solar corona
… the reconnection site. Such jets, as observed in soft X-rays with the Yohkoh satellite, are spatially and temporally associated with beams of nonthermal electrons (in terms of the so-called type III metric radio bursts) propagating through the corona. A model that attempts to give an explanation …
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Influence of Aerosols During Amine-Based CO2 Capture: Evolution and Control
… of aerosol concentration, gas flow rate and soft X-Rays on collection efficiency was systematically evaluated. A modified Deutsch-Anderson model was developed for the PI-ESP and the experimental data was used to determine regression coefficients.Part IV: Flue gas aerosol sampling was …
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