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Showing 1 to 20 of 82 for “"Krypton"”.
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Optical Processes in Krypton and Krypton(2)fluoride: Absolute Cross-Sections for Multiphoton Ionization of Krypton (1S(0)), Photoionization of Metastable Atomic and Molecular States of Krypton, Andabsorption of Krypton(2)fluoride (4-Doublet-Gamma)
A microwave absorption apparatus has been used to measure a cross section for the three-photon, resonantly-enhanced ionization of Kr(('1)S(,0)) at 193 nm. The presence of a two-photon resonance with the Kr 6p 3/2 (,2) level enabled the generation of large electron densities and a measurement of the …
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Excitation Spectroscopy of Krypton Molecular Rydberg States
… (lamda) (LESSTHEQ) 545 nm, and Rydberg series of krypton dimers have been observed. The most pronounced peaks in the spectrum have been attributed to np('3)(PI)(,g) (<---) 5s('3)(SIGMA)(,u)('+) (7 (LESSTHEQ) n (LESSTHEQ) 18) transitions. The series limit and quantum defect, (delta), for the …
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The velocity of sound in solid krypton
… have been carried out on specimens of solid krypton prepared in a rigid-tail helium cryostat. Values were obtained from polycrystalline specimens for longitudinal sound waves from 52 to 115 K and transverse sound waves from 95 to 115 K, and from a single crystal for longitudinal sound waves …
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Photoassociation of krypton and fluorine collision pairs
The photoassociation spectrum of Kr-F collision pairs in thermal equilibrium (293$\sp\circ$K) to KrF(B) has been observed using a laser-induced fluorescence technique with a tunable probe over the wavelength range 219 nm $\leq$ $\lambda$ $\leq$ 250 nm. The spectrum was then analyzed by numerical …
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Inter-Rydberg excitation spectroscopy of krypton dimers
An excitation spectrum of the krypton dimer 6p$\sp3\Pi\sb{\rm g}(0\sbsp{g}{-})$ $\gets$ 5s$\sp3\Sigma\sbsp{\rm u}{+}(1\sb{\rm u}$, 0$\sbsp{\rm u}{-})$ transition has been observed over 525 nm $\leq$ $\lambda$ $\leq$ 545 nm. An argon fluoride excimer laser was used to excite the atomic krypton 6p …
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The X-ray Debye temperature of solid krypton
… on two large single crystal specimens of solid krypton. These data have been interpreted in terms of a Debye characteristic temperature, 8 M "" according to the method suggested by Nicklow and Young. The specimens were prepared and maintained in a specially designed and constructed rigid-tail …
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Nuclear Forward-Scattering of Synchrotron Radiation From Krypton: First Observation and Application to the Study of Lattice Dynamics in Near-Monolayer Krypton-on-Graphite
<p>Since 1985 nuclear-resonant scattering, and in particular nuclear forward-scattering, of synchrotron radiation has been observed in a select few Mossbauer isotopes including: <sup>57</sup>Fe, <sup>119</sup>Sn, <sup>169</sup>Tm. For the first time, nuclear forward-scattering from the 9.4 keV …
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Equilibrium vacancy concentration measurements and thermal properties of solid krypton
… mm diam cylindrical specimens of 99.995% purity krypton. The specimens were prepared and held unconstrained in a rigid-tail cryostat in which specimen temperatures could be precisely controlled. The data show a divergence between the bulk and lattice expansions at the higher temperatures which …
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X-ray diffraction study of compressed solid argon and krypton
… the melting curves of solid argon and solid krypton and to measure changes in vacancy concentrations along quasi-isochores for both these substances. The uncertainty of the lattice parameters obtained along melting was estimated to be 27 ppm. These measurements are believed to be the most …
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Investigation of Krypton bubbles in copper using x-ray techniques
… containing a high concentration (3 atomic %) of krypton is performed by X-ray diffraction techniques. Stress determination and phase analysis are carried out to determine the residual stress of the host copper metal and the internal pressure of the krypton bubbles. Lattice parameter determination …
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Optical Excitation of Metastable Krypton and Photoassociative Spectroscopy of Ultracold RbAr
… excitation methods to produce metastable-state krypton. The high energies required to excite rare gases out of their ground state present a unique challenge in the context of laser experiments. Laser physics work with rare gases often relies on excitation within an RF discharge. All-optical …
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Fabrication of an Apparatus for All-Optical Production of Metastable Krypton
<p>Atom Trap Trace Analysis (ATTA) has made radiokrypton dating of polar ice and groundwater samples a possibility for scientists all over the world, allowing them to date samples further back in time and more accurately than other methods. However, this technique is hampered by the 36-hour …
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A krypton VUV photoionization source for gas chromatography and mass spectrometry.
The use of a coaxial krypton discharge lamp to selectively photoionize samples in a complex matrix is described. The lamp produces a krypton line emission spectrum with available photon energies of 10.0 and 10.6 eV. When used as a photoionization mass spectrometer source, conditions can be created …
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Characterization of a Low Current LaB6 Heaterless Hollow Cathode with Krypton Propellant
… investigated. The cathode is characterized using krypton as propellant at varying flow rates, discharge currents and cathode-anode distances. Voltage probes, used to make direct voltage measurements in the ignition circuit, are the only diagnostic tool used experimentally. A plasma model is used …
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Photoassociative Spectroscopy of Ultracold Argon and Krypton Confined in a Magneto Optical Trap
… (PAS) studies conducted separately in argon and krypton. For each species, we have studied transitions near two different atomic limits ns[3/2]<sub>2</sub> —> np[5/2]<sub>2</sub> and ns[3/2]<sub>2</sub> —» np[5/2]<sub>3</sub>where n = 4 for argon and n = 5 for krypton. The former atomic …
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Changes in the near-surface stress in titanium caused by krypton ion-implantation
In this work, the effect of krypton implantation on the morphology of titanium samples is investigated through scanning electron microscopy (SEM). Rutherford backscattering spectrometry (RBS) was also used to determine the dose and depth of implanted krypton. The krypton profiile in titanium, and …
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Untersuchungen der Wellenlängenabhängigkeit von Ionisationsprozessen von Xenon und Krypton in starken ultra-kurzen Laserfeldern
… Doppelionisation (NSDI) von Xenon und Krypton <br>bei verschiedenen Wellenlängen im nahen Infrarot. <br> <br>Das erste Kapitel der Arbeit führt in die Physik der <br>Wechselwirkung von Atomen mit starken Laserfeldern ein und <br>diskutiert die wichtigsten Theorien und experimentellen …
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