A5046016787- Nuclear physics research studies
- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Particle accelerators and beam dynamics
- Astronomical and nuclear sciences
- Atomic and Molecular Physics
- Advanced Chemical Physics Studies
- Superconducting Materials and Applications
- Quantum Chromodynamics and Particle Interactions
- Radiopharmaceutical Chemistry and Applications
- Advanced NMR Techniques and Applications
- Magnetic confinement fusion research
- Advanced Battery Technologies Research
- Rare-earth and actinide compounds
- Radiation Effects in Electronics
- Cold Fusion and Nuclear Reactions
- Radioactive element chemistry and processing
- Radiation Detection and Scintillator Technologies
- Particle Accelerators and Free-Electron Lasers
- Radiation Therapy and Dosimetry
- Fusion materials and technologies
Oak Ridge National Laboratory
1996-2022
Los Alamos National Laboratory
1998-2013
Lawrence Livermore National Laboratory
2000-2004
North Carolina State University
2002
National Technical Information Service
2000
Office of Scientific and Technical Information
2000
Florida State University
1994-1999
University of Pittsburgh
1996
National Nuclear Energy Commission
1996
Instituto de Pesquisas Energéticas e Nucleares
1996
Absolute partial cross sections for production of 45 discrete $\ensuremath{\gamma}$ rays in the $^{238}\mathrm{U}(n,xn\ensuremath{\gamma})$ reactions with $x\ensuremath{\leqslant}4$ are reported incident-neutron energies range $1\phantom{\rule{0.3em}{0ex}}\text{MeV}<{E}_{n}<100\phantom{\rule{0.3em}{0ex}}\text{MeV}$. A germanium-detector array $\ensuremath{\gamma}$-ray detection and ``white''-neutron source at LANSCE∕WNR were used measurement. The energy incident neutrons was determined...
The ${}^{239}\mathrm{Pu}{(n,2n)}^{238}\mathrm{Pu}$ cross section has been deduced using a combination of measured partial $\ensuremath{\gamma}$-ray sections and enhanced Hauser-Feshbach reaction modeling from threshold to ${E}_{n}<~20 \mathrm{MeV}.$ Eight ${}^{239}\mathrm{Pu}(n,2n\ensuremath{\gamma}{)}^{238}\mathrm{Pu}$ were the GEANIE spectrometer, time-of-flight technique, energetic neutrons produced at LANSCE/WNR facility. $(n,2n)$ was obtained by multiplying sum observed noncoincident...
Prompt $\ensuremath{\gamma}$ rays from the neutron-induced fission of ${}^{235}\mathrm{U}$ have been studied using GEANIE spectrometer situated at LANSCE/WNR ``white'' neutron facility. Transitions characteristic specific fragments were identified a combination single-fold and coincidence $\ensuremath{\gamma}$-ray analysis. Gamma-ray production cross sections obtained as function incident energy time-of-flight technique. Yields extracted for 206 produced by 56 distinct...
High-spin states in $^{86}\mathrm{Mo}$ were studied by means of the fusion evaporation reaction $^{58}\mathrm{Ni}$${(}^{32}$S,2p2n${)}^{86}$Mo at 135 MeV beam energy. Charged-particle-\ensuremath{\gamma}\ensuremath{\gamma} and -\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\gamma} coincidences recorded with early implementation GAMMASPHERE array MICROBALL charged-particle detection system used to largely extend level scheme ${\mathit{T}}_{\mathit{z}}$=1 nucleus a possible spin...
High-spin states in $^{78}\mathrm{Br}$ have been studied up to an excitation energy of approximately 6 MeV and a spin 17\ensuremath{\Elzxh} using the $^{70}\mathrm{Zn}$${(}^{11}$B,3n${)}^{78}$Br reaction at beam 45 MeV. The properties observed rotational bands, including moments inertia, signature splitting, inversion, are discussed within context cranked shell model. It is shown that cranked-shell-model calculations able reproduce experimentally inversion positive-parity yrast bands odd-odd...
High-spin states in $^{79}\mathrm{Kr}$ were studied using the $^{65}\mathrm{Cu}$${(}^{18}$O,p3n) reaction at 65 MeV Florida State University Tandem-LINAC facility. Prompt \ensuremath{\gamma}-\ensuremath{\gamma} coincidences observed Pitt-FSU detector array. Twelve new found, along with 19 transitions. The yrast positive- and negative-parity bands extended up to spins of (45/${2}^{+}$) (31/${2}^{\mathrm{\ensuremath{-}}}$), respectively. Spin assignments made based on directional correlation...
High angular momentum states in odd-odd ${}^{86}\mathrm{Nb}$ were populated through the ${}^{58}\mathrm{Ni}{(}^{32}\mathrm{S},3pn)$ reaction at 135 MeV. Recoiling nuclei stopped a thick Ta backing. Prompt multi-$\ensuremath{\gamma}$ coincidences with evaporated charged particles detected using full array of Gammasphere and Microball. Mean lifetimes 51 levels measured Doppler-shift attenuation method. Strongly alternating magnetic dipole transition strengths observed yrast positive-parity...
High angular momentum states in ${}^{86}\mathrm{Zr}$ were populated through the ${}^{58}\mathrm{Ni}{(}^{32}\mathrm{S},4p)$ reaction at 135 MeV using 88-In. Cyclotron Lawrence Berkeley National Laboratory. Recoiling nuclei stopped a thick Ta backing. Prompt multi-$\ensuremath{\gamma}$ coincidences with evaporated charged particles detected full array of GAMMASPHERE and MICROBALL. Mean lifetimes 36 levels measured Doppler-shift attenuation method. Transition quadrupole moments ${Q}_{t}$ found...
Lifetimes of 34 high-spin levels in ${}^{81}\mathrm{Y}$ were measured using the Doppler-shift attenuation method. The states populated ${}^{58}\mathrm{Ni}{(}^{32}\mathrm{S},2\ensuremath{\alpha}p)$ reaction at 135 MeV, and recoils stopped a thick Ta backing. Prompt multi-$\ensuremath{\gamma}$ coincidences detected GAMMASPHERE, evaporated charged particles with MICROBALL. Transition quadrupole moments inferred from lifetimes lowest positive- negative-parity bands show relatively gradual...
Positive-parity high-spin states in the odd-proton nuclei ${}^{83}\mathrm{Rb}$ and ${}^{85}\mathrm{Y}$ have been populated via ${}^{68}\mathrm{Zn}{(}^{18}\mathrm{O},p2n)$ reaction at 56 MeV ${}^{59}\mathrm{Co}{(}^{28}\mathrm{Si},2p)$ 99 up to ${(37/2}^{+})$ ${(33/2}^{+}),$ respectively. In both band crossings observed a spin of $21/2$ interpreted as resulting from alignment ${g}_{9/2}$ neutron pair, other with 46 neutrons. three-quasiparticle excitations, signature splitting total Routhian...
Excitation functions from the interaction of fast neutrons (up to an energy 250 MeV) on a target ${}^{92}\mathrm{Mo}$ have been measured. Yields determined for reaction \ensuremath{\gamma} rays ${}^{88\ensuremath{-}92}\mathrm{Mo},$ ${}^{88\ensuremath{-}92}\mathrm{Nb},$ ${}^{86\ensuremath{-}91}\mathrm{Zr},$ ${}^{84\ensuremath{-}86,88}\mathrm{Y},$ and ${}^{80,82\ensuremath{-}86}\mathrm{Sr}.$ These results are compared with model calculations using GNASH code which takes into account compound...
Neutron-induced reactions on ${}^{196}\mathrm{Pt}$ were studied over the neutron energy range from 1 to 250 MeV. A ``white'' beam was provided by spallation source of Weapons Neutron Research facility at Los Alamos Science Center. The prompt reaction $\ensuremath{\gamma}$ rays measured with large-scale Compton-suppressed Ge spectrometer GEANIE. incident determined time-of-flight technique. Excitation functions for $\ensuremath{\gamma}$-ray transitions in...
States in ${}^{92}\mathrm{Mo}$ have been observed with the ${(n,n}^{\ensuremath{'}}\ensuremath{\gamma})$ reaction spallation neutrons produced at LANSCE-WNR facility. Gamma rays were detected GEANIE spectrometer, and neutron energies determined by time-of-flight method. Combining excitation function $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidence analysis, 13 new levels deduced. The level scheme has extended considerably for low- to medium-spin below 5 MeV energy.
Levels in ${}^{196}\mathrm{Pt}$ have been studied via the ${}^{196}\mathrm{Pt}{(n,n}^{\ensuremath{'}}\ensuremath{\gamma})$ reaction for a range of neutron energies from 1 to 8 MeV. A ``white'' spectrum neutrons was produced at LANSCE/WNR facility, and incident energy determined by time-of-flight technique. Analysis measured $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidence data \ensuremath{\gamma}-ray excitation functions, obtained with large-scale Compton-suppressed Ge spectrometer...
Two experiments have been performed using the ${}^{58}\mathrm{Ni}{(}^{32}\mathrm{S},3p)$ reaction at 135 MeV with Gammasphere and Microball to study high-spin structure of transitional nucleus ${}^{87}\mathrm{Nb}.$ The first experiment a thin target provided considerable extension refinement level scheme, as well firm spin assignments from directional correlation oriented nuclei. Sub-picosecond lifetimes were measured in second backed-target Doppler-shift attenuation method. imply rather...
Rotational bands in $^{175}\mathrm{Lu}$ have been extended through investigation with the $(n,{n}^{\ensuremath{'}}\ensuremath{\gamma})$ reaction. Spallation neutrons bombarded Lu samples, and resulting $\ensuremath{\gamma}$ rays were detected a large-scale Compton-suppressed Ge detector array. Prompt- delayed-$\ensuremath{\gamma}\ensuremath{\gamma}$ coincidences used to extend $5∕{2}^{+}[402]$ band spin $17∕2$, $3∕{2}^{+}[411]$ $11∕2$, $1∕{2}^{+}[411]$ $15∕2$, $1∕{2}^{\ensuremath{-}}[541]$...
Discrete \ensuremath{\gamma}-ray spectra have been measured as a function of incident neutron energy for nuclei produced in the ${}^{196}\mathrm{Pt}(n,xn\ensuremath{\gamma})$ reactions. Spectroscopy was done using large-scale Compton suppressed Ge spectrometer GEANIE. The ``white'' source beam at Los Alamos Neutron Science WNR facility. Reaction determined time-of-flight technique. Reaction-channel yields were inferred from intensity sum ${2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+}$ and...
Absolute partial γ-ray cross sections for discrete production in the 239Pu(n,2nγi)238Pu reaction have been measured. The experiments were performed at LANSCE/WNR on 60R neutron flight path. Reaction γ-rays measured using large-scale Compton-suppressed array of Ge detectors, GEANIE. motivation this experiment, an overview cross-section measurement, and introduction to main experimental issues will be presented. energy resolution detectors allowed identification γ rays above background sample...
An experimental program for studying the properties of fission induced by intermediate energy neutrons has been started at Los Alamos Neutron Science Center (LANSCE). Experiments using GEANIE high-resolution gamma-ray spectrometer were performed to extract excitation functions products obtained from a 238U target. Results singles data xenon isotopes are presented illustrate method, and show that rotational ground-state-band transitions suited extraction production cross-sections even-even...
High-spin states of $^{143}\mathrm{Nd}$ have been studied using the $^{130}\mathrm{Te}$${(}^{18}$O,5n) reaction at 85 MeV. The yrast observed up to a tentatively assigned spin 45/2 can be described in remarkably simple way by weak coupling an ${\mathit{f}}_{7/2}$ neutron $^{142}\mathrm{Nd}$ core nucleus. Our results demonstrate that is one best known examples high angular momentum.