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Low energy gamma-transitions in Pu{sup 238} and Pu{sup 240}

Description: We investigated electron and gamma spectra of mixtures of isotopes of curium. This was done on a beta spectrometer with double focusing at an angle of {pi}{radical}2 and on a scintillation gamma spectrometer with a 40 {times} 40 mm NAI(Tl) single crystal detector. The observed electron spectrum are interpolated and presented. Also, experimental results of the ratio of conversion at L and M subshells are presented and compared to theoretical values.
Date: March 27, 1967
Creator: Akalaev, G. G.; Vartanov, N. A. & Samoilov, P. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MCP code fluorescence-routine revision

Description: A new method is described for treating fluorescence, which replaces the original subroutine of the Monte Carlo photon code (MCP), and eliminates its most undesirable features. The major changes include (a) elimination of the very inaccurats 1/E/sup 3/ law for photoelectric cross section, b) updating of relative intensities of K-fluorescence lines, (c) elimination of fluorescence from shells other than K and L, and (d) provision for secondary L-fluorescence. Except for the latter, the previous c… more
Date: May 1, 1973
Creator: Everett, C.J. & Cashwell, E.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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L-shell emission from high-Z solid targets by intense 10{sup 19}W/cm{sup 2} irradiation with a 248nm laser

Description: Efficient (1.2% yield) multikilovolt x-ray emission from Ba(L) (2.4--2.8{angstrom}) and Gd(L) (1.7--2.1{angstrom}) is produced by ultraviolet (248nm) laser-excited BaF{sub 2} and Gd solids. The high efficiency is attributed to an inner shell-selective collisional electron ejection. Much effort has been expended recently in attempts to develop an efficient coherent x-ray source suitable for high-resolution biological imaging. To this end, many experiments have been performed studying the x-ray e… more
Date: January 5, 2000
Creator: Nelson, T. R.; Borisov, A. B. & Boyer, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy states and energy flow near the transition states of unimolecular reactions

Description: The use of lasers with jet-cooled samples has improved energy and angular momentum resolution for the reactant and time resolution for the rate constant by orders of magnitude. The resolution of product quantum states has added a new dimension to unimolecular dynamics. In the past, the geometry, barrier height and vibrational frequencies of the transition state in RRKM theory were adjusted to fit thermal unimolecular reaction rate data. There have been successful quantitative tests of the abili… more
Date: October 1, 1994
Creator: Moore, C. Bradley
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron transfer and physical and chemical processes at low temperatures

Description: We summarize some phenomena that occur at temperatures of the order of 15K, and are dominated by quantum mechanical tunneling. Although electron tunneling dominates many conduction processes at low temperatures, we discuss evidence that phenomena like oxidation, as well as the solution of alkali metals in ammonia, can also be dominated by electron tunneling. Both phenomena demonstrate that the chemical potential of a metastable system can equilibrate at low temperatures by electron tunneling. T… more
Date: October 1, 1995
Creator: Strongin, M.; Xia, B. & Jacobsen, F. M.
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Partner: UNT Libraries Government Documents Department
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Molecular iodine absolute frequencies. Final report

Description: Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute frequency determinations were made w… more
Date: June 25, 1990
Creator: Sansonetti, C. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pressure dependence of Se absorption lines in AlSb

Description: Using far infrared absorption spectroscopy, the authors have investigated electronic transition spectra of Se donors in AlSb as a function of hydrostatic pressure. At least two distinct ground to bound excited state transition lines, which depend quadratically on the pressure, can be seen. At pressures between 30 and 50 kbar, evidence of an anti-crossing between one of the electronic transitions and a peak which they attribute to the 2 zone center LO phonon mode can be seen.
Date: September 1, 1996
Creator: Hsu, L.; Haller, E.E. & Ramdas, A.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear decay data for selected radionuclides

Description: Contained in this report are tabulations of the atomic and nuclear radiations emitted by 194 radioactive nuclides. The nuclei included comprise most of those currently of interest in medical practice or research, health physics, industry, nuclear power, environmental impact studies, and as reference standards. Listed in tabular form are recommended values for half-lives, energies, intensities (probabilities per decay), and equilibrium absorbed-dose constants for each of the atomic and nuclear r… more
Date: March 1, 1976
Creator: Martin, M.J. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Soft Radiative Strength in Warm Nuclei

Description: We present data on the soft (E{sub {gamma}} < 3-4 MeV) radiative strength function (RSF) for electromagnetic transitions between warm states (i.e. states several MeV above the yrast line) from two different types of experiments. The Oslo method provides data on the total level density and the sum (over all multipolarities) of all RSFs by sequential extraction from primary-{gamma} spectra. Measurements of two-step-decay spectra following neutron capture yields two-step-cascade (TSC) intensiti… more
Date: September 29, 2005
Creator: Schiller, A.; Voinov, A.; Agvaanluvsan, U.; Algin, E.; Becker, J.; Belgya, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-ray fluorescence/Auger-electron coincidence spectroscopy of vacancy cascades in atomic argon

Description: Argon L{sub 2.3}-M{sub 2.3}M{sub 2.3} Auger-electron spectra were measured in coincidence with K{alpha} fluorescent x-rays in studies of Ar K-shell vacancy decays at several photon energies above the K-threshold and on the 1s-4p resonance in atomic argon. The complex spectra recorded by conventional electron spectroscopy are greatly simplified when recorded in coincidence with fluorescent x-rays, allowing a more detailed analysis of the vacancy cascade process. The resulting coincidence spectra… more
Date: December 1, 1996
Creator: Arp, U.; LeBrun, T.; Southworth, S.H.; Jung, M. & MacDonald, M.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Amplitude modulation of atomic wave functions. Final report

Description: The major theoretical advance has been to show that one can modulate Rydberg wave functions using either of two methods: (1) the amplitude modulation technique which depends on autoionization to deplete part of the wave function, or (2) a phase modulation method, which uses a change in the core potential to create a localized phase shift in the wave function. Essentially, these two methods can both be seen as using the core potential to change the Rydberg wave function, using the imaginary part… more
Date: November 1, 1998
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The calculation of satellite line structures in highly stripped plasmas

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Recently developed high-resolution x-ray spectrographs have made it possible to measure satellite structures from various plasma sources with great detail. These lines are weak optically thin lines caused by the decay of dielectronic states and generally accompany the resonance lines of H-like and He-like ions. The Los Alamos atomic physics and kine… more
Date: November 1, 1998
Creator: Abdallah, J. Jr.; Kilcrease, D. P.; Faenov, A. Ya. & Pikuz, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of Neon-Like and Nickel-Like Ions Lasing on the J = 0 {r_arrow} 1 Line Using the Prepulse and Multiple Pulse Techniques

Description: The authors discuss the use of a prepulse technique to achieve lasing in low-Z neon-like ions on the 3p {r_arrow} 3s(J = 0 {r_arrow} 1) transition. Lasing has now been observed on this transitions for neon-like ions from chlorine to selenium with wavelengths ranging from 528 {angstrom} to 182 {angstrom}. For the germanium targets they present two dimensional space resolves images of the laser output with magnification of ten. Using a gas puff target as an alternative to the prepulse technique, … more
Date: November 1, 1995
Creator: Nilsen, J.; Moreno, J. C.; Da Silva, L. B.; Barbee, T. W., Jr.; Li, Y.; Lu, P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isoelectronic behavior of resonant and intercombination lines in MgI-like ions

Description: Radiative transitions with very different characteristic rates can serve as important diagnostics of local conditions in a plasma. Here, the observed intensity ratio of the 3s{sup 2} {sup 1}S{sub 0} - 3s3p {sup 1}P{sub 1} to the 3s{sup 2} {sup 1}S{sub 0} - 3s3p {sup 3}P{sub 1} transitions in MgI-like ions has always presented those who model plasma spectra with a challenge; the observed intensity of the intercombination line is always several times greater than what simple models predict. The a… more
Date: August 1, 1995
Creator: Fournier, K. B.; Goldstein, W. H.; Finkenthal, M.; Bell, R. E. & Terry, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Structure of Nuclei Far from Stability

Description: From among a number of important nuclear structure results that have emerged from our research program during the past few years, two stand out as being of extra significance. These are: (a) the identification of a diabatic coexisting structure in {sup 187}Au which arises solely from differences in proton occupation of adjacent oscillator shells, and (b) the realization of a method for estimating EO strength in nuclei and the resulting prediction that the de-excitation of superdeformed bands ma… more
Date: February 25, 1999
Creator: Zganjar, E.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quantum phase space theory for the calculation of v{center_dot}j vector correlations

Description: The quantum state-counting phase space theory commonly used to describe barrierless dissociation is recast in a helicity basis to calculate photofragment v{center_dot}j correlations. Counting pairs of fragment states with specific angular momentum projection numbers on the relative velocity provides a simple connection between angular momentum conservation and the v{center_dot}j correlation, which is not so evident in the conventional basis for phase space state counts. The upper bound on the o… more
Date: July 1, 1995
Creator: Hall, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lifetime measurements and dipole transition rates for superdeformed states in {sup 190}Hg.

Description: The Doppler-shift attenuation method was used to measure life-times of superdeformed (SD) states for both the yrast and the first excited superdeformed band of {sup 190}Hg. Intrinsic quadruple moments Q{sub 0} were extracted. For the first time, the dipole transition rates have been extracted for the inter-band transitions which connect the excited SD band to the yrast states in the second minimum. The results support the interpretation of the excited SD band as a rotational band built on an oc… more
Date: March 24, 1999
Creator: Amro, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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