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Analysing the Effect on CMB in a Parity and Charge Parity Violating Varying Alpha Theory
In this paper we study in detail the effect of our recently proposed model of parity and charge-parity (PCP) violating varying alpha on the Cosmic Microwave Background (CMB) photon passing through the intra galaxy-cluster medium (ICM). The ICM is well known to be composed of magnetized plasma. According to our model, the polarization and intensity of the CMB would be affected when traversing through the ICM due to non-trivial scalar photon interactions. We have calculated the evolution of such polarization and intensity collectively, known as the stokes parameters of the CMB photon during its journey through the ICM and tested our results against the Sunyaev-Zel'dovich (SZ) measurement on Coma galaxy cluster. Our model contains a PCP violating parameter, {beta}, and a scale of alpha variation {omega}. Using the derived constrained on the photon-to-scalar conversion probability, {bar P}{sub {gamma}{yields}{phi}}, for Coma cluster in ref.[34] we found a contour plot in the ({omega},{beta}) parameter plane. The {beta} = 0 line in this parameter space corresponds to well-studied Maxwell-dilaton type models which has lower bound on {omega} {approx}> 6.4 x 10{sup 9} GeV. In general, as the absolute value of {beta} increases, lower bound on {omega} also increases. Our model in general predicts …
Date:
September 14, 2012
Creator:
Maity, Debaprasad; /NCTS, Taipei /Taiwan, Natl. Taiwan U.; Chen, Pisin & /NCTS, Taipei /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC
Object Type:
Article
System:
The UNT Digital Library
[Fraternity student at the Omega Delta Phi Fraternity table]
Photograph of a fraternity student standing at the Chaotic Alpha Chi Chapter of Omega Delta Phi Fraternity table. The student is posing for his picture to be taken, dressed in his fraternities colors and holding up his fraternities' hand sign. The poster board is intricately designed as a castle, with colors of black and red. The photograph was taken during UNT's Founder's Day event, the celebration of UNT's birthday.
Date:
September 10, 2021
Creator:
Esparza, Anna
Object Type:
Photograph
System:
The UNT Digital Library
Two Dimensional Simulations of Plastic-Shell, Direct-Drive Implosions on OMEGA
Multidimensional hydrodynamic properties of high-adiabat direct-drive plastic-shell implosions on the OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] are investigated using the multidimensional hydrodynamic code, DRACO. Multimode simulations including the effects of nonuniform illumination and target roughness indicate that shell stability during the acceleration phase plays a critical role in determining target performance. For thick shells that remain integral during the acceleration phase, target yields are significantly reduced by the combination of the long-wavelength ({ell} < 10) modes due to surface roughness and beam imbalance and the intermediate modes (20 {le} {ell} {le} 50) due to single-beam nonuniformities. The neutron-production rate for these thick shells truncates relative to one-dimensional (1-D) predictions. The yield degradation in the thin shells is mainly due to shell breakup at short wavelengths ({lambda} {approx} {Delta}, where {Delta} is the in-flight shell thickness). The neutron-rate curves for the thinner shells have significantly lower amplitudes and a fall-off that is less steep than 1-D rates. DRACO simulation results are consistent with experimental observations.
Date:
September 27, 2004
Creator:
Radha, P. B.; Goncharov, V. N.; Collins, T. B.; Delettrez, J. A.; Elbaz, Y.; Glebov, V. Y. et al.
Object Type:
Article
System:
The UNT Digital Library
Alpha Radiolysis of Sorbed Water on Uranium Oxides and Uranium Oxyfluorides
The radiolysis of sorbed water and other impurities contained in actinide oxides has been the focus of a number of studies related to the establishment of criteria for the safe storage and transport of these materials. Gamma radiolysis studies have previously been performed on uranium oxides and oxyfluorides (UO{sub 3}, U{sub 3}O{sub 8}, and UO{sub 2}F{sub 2}) to evaluate the long-term storage characteristics of {sup 233}U. This report describes a similar study for alpha radiolysis. Uranium oxides and oxyfluorides (with {sup 238}U as the surrogate for {sup 233}U) were subjected to relatively high alpha radiation doses (235 to 634 MGy) by doping with {sup 244}Cm. The typical irradiation time for these samples was about 1.5 years, which would be equivalent to more than 50 years irradiation by a {sup 233}U sample. Both dry and wet (up to 10 wt % water) samples were examined in an effort to identify the gas pressure and composition changes that occurred as a result of radiolysis. This study shows that several competing reactions occur during radiolysis, with the net effect that only very low pressures of hydrogen, nitrogen, and carbon dioxide are generated from the water, nitrate, and carbon impurities, respectively, associated with the …
Date:
September 10, 2003
Creator:
Icenhour, A.S.
Object Type:
Report
System:
The UNT Digital Library
[Three students from the Alpha Kappa Psi Professional Business Fraternity]
Photograph of three students from the Chi Omega Chapter of the Alpha Kappa Psi Professional Business Fraternity. The students are standing at their table and poster board presentation ready to engage with interested students. The photograph was taken during UNT's Founder's Day event, the celebration of UNT's birthday.
Date:
September 10, 2021
Creator:
Esparza, Anna
Object Type:
Photograph
System:
The UNT Digital Library
[Photograph 2012.201.B0979.0591]
Photograph used for a story in the Oklahoma Times newspaper. Caption: "Sales pitch for Alpha Chi Omega Sorority at Oklahoma City University is given Ardmore rushee Elaine Massad, left, by Alpha Chi Marianne Brown, Albuquerque, N, M, senior, as the girls admire recent trophies the sorority has won."
Date:
September 10, 1969
Creator:
Fisher, Don
Object Type:
Photograph
System:
The Gateway to Oklahoma History
[Photograph 2012.201.B0904.0087]
Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Mrs. Don F. Mahaffey, left, and Mrs. Charles F. Miller / Alpha Chi Omega Alumnae."
Date:
September 2, 1976
Creator:
Miller, Joe
Object Type:
Photograph
System:
The Gateway to Oklahoma History
[Photograph 2012.201.OVZ001.9043]
Photograph used for a story in the Daily Oklahoman newspaper. Caption: "This is a view of the Student Union ballroom, part of the $2,300,000 renovation and expension program. In the picture are Mary Jean Straw, senior, president of Alpha Chi Omega, whose home is Senta Fe, N.M., and Liew Keller, Phi Kappa Psi senior, of 2330 NW 19, Oklahoma City, members of the union board of activities."
Date:
September 13, 1951
Creator:
Albright, Bob
Object Type:
Photograph
System:
The Gateway to Oklahoma History
Fundamentals of ICF Hohlraums
On the Nova Laser at LLNL, we demonstrated many of the key elements required for assuring that the next laser, the National Ignition Facility (NIF) will drive an Inertial Confinement Fusion (ICF) target to ignition. The indirect drive (sometimes referred to as ''radiation drive'') approach converts laser light to x-rays inside a gold cylinder, which then acts as an x-ray ''oven'' (called a hohlraum) to drive the fusion capsule in its center. On Nova we've demonstrated good understanding of the temperatures reached in hohlraums and of the ways to control the uniformity with which the x-rays drive the spherical fusion capsules. In these lectures we will be reviewing the physics of these laser heated hohlraums, recent attempts at optimizing their performance, and then return to the ICF problem in particular to discuss scaling of ICF gain with scale size, and to compare indirect vs. direct drive gains. In ICF, spherical capsules containing Deuterium and Tritium (DT)--the heavy isotopes of hydrogen--are imploded, creating conditions of high temperature and density similar to those in the cores of stars required for initiating the fusion reaction. When DT fuses an alpha particle (the nucleus of a helium atom) and a neutron are created releasing …
Date:
September 30, 2005
Creator:
Rosen, M D
Object Type:
Article
System:
The UNT Digital Library
Improved Hydrogen Gas Getters for TRU Waste -- Final Report
Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage containers. For that reason, the Nuclear Regulatory Commission limits the flammable gas (hydrogen) concentration in the Transuranic Package Transporter-II (TRUPACT-II) containers to 5 vol% of hydrogen in air, which is the lower explosion limit. Consequently, a method is needed to prevent the build up of hydrogen to 5 vol% during the storage and transport of the TRUPACT-II containers (up to 60 days). One promising option is the use of hydrogen getters. These materials scavenge hydrogen from the gas phase and irreversibly bind it in the solid phase. One proven getter is a material called 1,4-bis (phenylethynyl) benzene, or DEB, characterized by the presence of carbon-carbon triple bonds. Carbon may, in the presence of suitable precious metal catalysts such as palladium, irreversibly react with and bind hydrogen. In the presence of oxygen, the precious metal may also eliminate hydrogen by catalyzing the formation of water. This reaction is called catalytic recombination. DEB has the needed binding rate and capacity for hydrogen that potentially could be generated in the TRUPACT II. Phases 1 and 2 of this project showed that uncoated DEB performed satisfactorily in lab scale tests. …
Date:
September 1, 2005
Creator:
Stone, Mark; Benson, Michael; Orme, Christopher; Luther, Thomas & Peterson, Eric
Object Type:
Report
System:
The UNT Digital Library
Integrated data base report - 1994: US spent nuclear fuel and radioactive waste inventories, projections, and characteristics
The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and U.S. Department of Energy (DOE) spent nuclear fuel and commercial and U.S. government-owned radioactive wastes. Except for transuranic wastes, inventories of these materials are reported as of December 31, 1994. Transuranic waste inventories are reported as of December 31, 1993. All spent nuclear fuel and radioactive waste data reported are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest DOE/Energy Information Administration (EIA) projections of U.S. commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste, transuranic waste, low-level waste, commercial uranium mill tailings, DOE Environmental Restoration Program contaminated environmental media, commercial reactor and fuel-cycle facility decommissioning wastes, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given through the calendar-year 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions.
Date:
September 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
WRAP Module 1 sampling strategy and waste characterization alternatives study
The Waste Receiving and Processing Module 1 Facility is designed to examine, process, certify, and ship drums and boxes of solid wastes that have a surface dose equivalent of less than 200 mrem/h. These wastes will include low-level and transuranic wastes that are retrievably stored in the 200 Area burial grounds and facilities in addition to newly generated wastes. Certification of retrievably stored wastes processing in WRAP 1 is required to meet the waste acceptance criteria for onsite treatment and disposal of low-level waste and mixed low-level waste and the Waste Isolation Pilot Plant Waste Acceptance Criteria for the disposal of TRU waste. In addition, these wastes will need to be certified for packaging in TRUPACT-II shipping containers. Characterization of the retrievably stored waste is needed to support the certification process. Characterization data will be obtained from historical records, process knowledge, nondestructive examination nondestructive assay, visual inspection of the waste, head-gas sampling, and analysis of samples taken from the waste containers. Sample characterization refers to the method or methods that are used to test waste samples for specific analytes. The focus of this study is the sample characterization needed to accurately identify the hazardous and radioactive constituents present in the …
Date:
September 30, 1994
Creator:
Bergeson, C. L.
Object Type:
Report
System:
The UNT Digital Library
Flammability Assessment Methodology Program Phase I: Final Report
The Flammability Assessment Methodology Program (FAMP) was established to investigate the flammability of gas mixtures found in transuranic (TRU) waste containers. The FAMP results provide a basis for increasing the permissible concentrations of flammable volatile organic compounds (VOCs) in TRU waste containers. The FAMP results will be used to modify the ''Safety Analysis Report for the TRUPACT-II Shipping Package'' (TRUPACT-II SARP) upon acceptance of the methodology by the Nuclear Regulatory Commission. Implementation of the methodology would substantially increase the number of drums that can be shipped to the Waste Isolation Pilot Plant (WIPP) without repackaging or treatment. Central to the program was experimental testing and modeling to predict the gas mixture lower explosive limit (MLEL) of gases observed in TRU waste containers. The experimental data supported selection of an MLEL model that was used in constructing screening limits for flammable VOC and flammable gas concentrations. The MLEL values predicted by the model for individual drums will be utilized to assess flammability for drums that do not meet the screening criteria. Finally, the predicted MLEL values will be used to derive acceptable gas generation rates, decay heat limits, and aspiration time requirements for drums that do not pass the screening limits. …
Date:
September 1, 1997
Creator:
Loehr, C. A.; Djordjevic, S. M.; Liekhus, K. J. & Connolly, M. J.
Object Type:
Report
System:
The UNT Digital Library
Material dynamics under extreme conditions of pressure and strain rate
Solid state experiments at extreme pressures (10-100 GPa) and strain rates ({approx}10{sup 6}-10{sup 8}s{sup -1}) are being developed on high-energy laser facilities, and offer the possibility for exploring new regimes of materials science. These extreme solid-state conditions can be accessed with either shock loading or with a quasi-isentropic ramped pressure drive. Velocity interferometer measurements establish the high pressure conditions. Constitutive models for solid-state strength under these conditions are tested by comparing 2D continuum simulations with experiments measuring perturbation growth due to the Rayleigh-Taylor instability in solid-state samples. Lattice compression, phase, and temperature are deduced from extended x-ray absorption fine structure (EXAFS) measurements, from which the shock-induced {alpha}-{omega} phase transition in Ti and the {alpha}-{var_epsilon} phase transition in Fe are inferred to occur on sub-nanosec time scales. Time resolved lattice response and phase can also be measured with dynamic x-ray diffraction measurements, where the elastic-plastic (1D-3D) lattice relaxation in shocked Cu is shown to occur promptly (< 1 ns). Subsequent large-scale molecular dynamics (MD) simulations elucidate the microscopic dynamics that underlie the 3D lattice relaxation. Deformation mechanisms are identified by examining the residual microstructure in recovered samples. The slip-twinning threshold in single-crystal Cu shocked along the [001] direction is shown to …
Date:
September 6, 2005
Creator:
Remington, Bruce A.; Allen, Patrick; Bringa, Eduaro; Hawreliak, Jim; Ho, Darwin; Lorenz, K. Thomas et al.
Object Type:
Article
System:
The UNT Digital Library
Mound Laboratory Progress Report for July 1964
None
Date:
September 25, 1964
Creator:
Eichelberger, J. F.; Grove, G. R. & Jones, L. V.
Object Type:
Report
System:
The UNT Digital Library
Crystallographic phase transitions in actinide metals as a function of pressure
We present first-principles calculations of the equilibrium volumes and crystal structures of the light actinides (Th--Pu). The calculated equilibrium volumes for fcc Th, bct Pu, {alpha}-U, and {beta}-Np are found to agree reasonably well with the experimental data, and when comparing the total energies of the bcc, fcc, bct, {alpha}-U, and {beta}-Np structures we obtain the correct crystal structures for all studied systems. Equilibrium volumes for Th--Pu, using a hypothetical fcc structure, have been calculated; although spin-orbit coupling is included in these calculations, the calculated equilibrium volume of Pu is smaller than for Np, in disagreement with experiment. Moreover, the calculated tetragonal elastic constant, C{prime}, is shown to be negative for bcc U, bcc Np, bcc Pu, and fcc Pu. Thus, our zero temperature calculations suggest that the bcc structure is unstable for these elements and that fcc Pu is also unstable. This is in conflict with experiment and we are led to the conclusion that temperature effects must be of crucial importance for stabilizing cubic structures in U, Np, and Pu. Further, as a function of decreasing volume we predict a crystal structure sequence fcc {yields} bct {yields} fcc in Th, a sequence {alpha}-U {yields} bct {yields} bcc in …
Date:
September 1, 1993
Creator:
Eriksson, O.; Soederlind, P.; Melsen, J.; Ahuja, R.; Johansson, B.; Wills, J. M. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurements of B to V(Gamma) Decays
The standard model has been highly successful at describing current experimental data. However, extensions of the standard model predict particles that have masses at energy scales that are above the electroweak scale. The flavor-changing neutral current processes of the B meson are sensitive to the influences of these new physics contributions. These processes proceed through loop diagrams, thus allowing new physics to enter at the same order as the standard model. New physics may contribute to the enhancement or suppression of rate asymmetries or the decay rates of these processes. The transition B {yields} V{gamma} (V = K*(892), {rho}(770), {omega}(782), {phi}(1020)) represents radiative decays of the B meson that proceed through penguin processes. Hadronic uncertainties limit the theoretical accuracy of the prediction of the branching fractions. However, uncertainties, both theoretical and experimental, are much reduced when considering quantities involving ratios of branching fractions, such as CP or isospin asymmetries. The most dominant exclusive radiative b {yields} s transition is B {yields} K*{gamma}. We present the best measurements of the branching fractions, direct CP, and isospin asymmetries of B {yields} K*{gamma}. The analogous b {yields} d transitions are B {yields} {rho}{gamma} and B {yields} {omega}{gamma}, which are suppressed by a factor …
Date:
September 2, 2010
Creator:
Yarritu, Aaron K.
Object Type:
Report
System:
The UNT Digital Library
Bibliography and index for nuclear reactions among light charged particles. Volume 26
A bibliography and index of experimental data from light charged particle induced nuclear reactions has been developed by searching the literature. To reduce both bulk and expense, this information is presented in the form of microfiche. Such data are useful for charged particle cross section evaluations and transport calculations. The incident particles considered were the five light isotopes p, d, t, /sup 3/He, and ..cap alpha... The criterion for including a reference was that the reference contain information about, at least, one reaction induced by an ion of one of the five light isotopes impinging on a target nucleus lighter than /sup 12/C. Once a reference was selected all reactions for target nuclei with Z less than or equal to 17 were included. A further criterion for selection was that the incident particle energy be less than or equal to 20 MeV. The bibliography consists of 1303 separate entries and is sorted three ways: (1) Author Citations arranges authors alphabetically, with associated reference numbers to data sets in which authors appear; (2) References Ordered Alphabetically arranges references and cross references in alphabetic order, with associated reference number, year, and authors; and (3) References Ordered Numerically shows the contents of the …
Date:
September 1, 1984
Creator:
Perkins, S.T.; Hansen, A.M. & Howerton, R.J.
Object Type:
Report
System:
The UNT Digital Library
Global Alfven eigenmodes in WELDELSTEIN 7-AS
In the presence of fast particle populations marginally stable global modes in the shear Alfven branch can be destabilized by wave particle resonances. This is particularly of concern in future large devices, where losses of resonant particles ({alpha}-particles in a reactor) may then limit the available heating power and also may cause damage of the first wall. In tokamaks TAE modes inside toroidicity induced gaps of the shear Alfven continua have been found. In stellarators with very weak shear like W7-AS low-n TAE-gaps do not occur but gaps below the shear Alfven continua with mode numbers m and n, if the resonant values {tau} = n/m do not exist in the plasma volume (k{sub {parallel}} = (m{sm_bullet}{tau} - n )/R {ne} 0 ). Under these conditions GAE modes with frequencies {omega}{sub GAE} < (k{sub {parallel}}{sm_bullet}V{sub A}){sub min} are the favoured modes. The investigation of GAE modes could also be of relevance in the case of advanced tokamak equilibria with flat or inverted q-profiles in the central region.
Date:
September 1, 1995
Creator:
Weller, A.; Goerner, C. & Jaenicke, R.
Object Type:
Article
System:
The UNT Digital Library
Produce and fish sampling program of Los Alamos National Laboratory's Environmental Surveillance Group
This report describes produce and fish sampling procedures of the Environmental Surveillance Group at the Los Alamos National Laboratory. The program monitors foodstuffs and fish for possible radioactive contamination from Laboratory operations. Data gathered in this program on radionuclide concentrations help to estimate radiation doses to Laboratory personnel and the public. 3 references, 7 figures, 2 tables.
Date:
September 1, 1984
Creator:
Salazar, J.G.
Object Type:
Report
System:
The UNT Digital Library
Search for Rare Multi-Pion Decays of the Tau Lepton Using the BABAR Detector
A search for the decay of the {tau} lepton to rare multi-pion final states is performed using the BABAR detector at the PEP-II asymmetric-energy e+e- collider. The analysis uses 232 fb-1 of data at center-of-mass energies on or near the {Upsilon}(4S) resonance. In the search for the {tau}- {yields} 3{pi}-2{pi}+2{pi}{sup 0}{nu}{sub {tau}} decay, we observe 10 events with an expected background of 6.5{sup +2.0}{sub -1.4} events. In the absence of a signal, we calculate the decay branching ratio upper limit {beta}({tau}- {yields} 3{pi}-2{pi}+2{pi}{sup 0}{nu}{sub {tau}}) < 3.4 x 10{sup -6} at the 90% confidence level. This is more than a factor of 30 improvement over the previously established limit. In addition, we search for the exclusive decay mode {tau}- {yields} 2{omega}{pi}-{nu}{sub {tau}} with the further decay of {omega} {yields} {pi}-{pi}+{pi}{sup 0}. We observe 1 event, expecting 0.4{sup +1.0}{sub -0.4} background events, and calculate the upper limit {beta}{tau}-{yields} 2{omega}{pi}-{nu}{sub {tau}} < 5.4 x 10{sup -7} at the 90% confidence level. This is the first upper limit for this mode.
Date:
September 18, 2007
Creator:
Ter-Antonyan, Ruben
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
High Energy X-Ray Source Generation by Short Pulse High Intensity Lasers
We are studying the feasibility of utilizing K{alpha} x-ray sources in the range of 20 to 100 keV as a backlighters for imaging various stages of implosions and high areal density planar samples driven by the NIF laser facility. The hard x-ray K{alpha} sources are created by relativistic electron plasma interactions in the target material after a radiation by short pulse high intensity lasers. In order to understand K{alpha} source characteristics such as production efficiency and brightness as a function of laser parameters, we have performed experiments using the 10 J, 100 fs JanUSP laser. We utilized single-photon counting spectroscopy and x-ray imaging diagnostics to characterize the K{alpha} source. We find that the K{alpha} conversion efficiency from the laser energy at 22 keV is {approx} 3 x 10{sup -4}.
Date:
September 2, 2003
Creator:
Park, H. S.; Koch, J. A.; Landen, O. L.; Phillips, T. W.; Goldsack, T.; Clark, E. et al.
Object Type:
Article
System:
The UNT Digital Library
A kinetic theory of trapped electron driven drift wave turbulence in a sheared magnetic field
A kinetic theory of collisionless and dissipative trapped electron driven drift wave turbulence in a sheared magnetic field is presented. Weak turbulence theory is employed to calculate the nonlinear electron and ion responses and to derive a wave kinetic equation that determines the nonlinear evolution of trapped electron mode turbulence. Saturated fluctuation spectrum is calculated using the condition of nonlinear saturation. The turbulent transport coefficients are in turn calculated using saturated fluctuation spectrum. Due to the disparity in the three different radial scale lengths of the slab-like eigenmode: {Delta} (trapped electron layer width), x{sub t} (turning point width) and x{sub i} (Landau damping point), {Delta} < x{sub t} < x{sub i}, we find that ion Compton scattering rather than trapped electron Compton scattering is the dominant nonlinear saturation mechanism. Ion Compton scattering transfers wave energy from short to long wavelengths where the wave energy is shear damped. As a consequence, a saturated fluctuation spectrum {vert bar}{phi}{vert bar}{sup 2}(k{sub {theta}}) {approximately} k{sub {theta}}{sup {minus}{alpha}} ({alpha} = 2 and 3 for the dissipative and collisionless regime, respectively) occurs for k{sub {theta}}{rho}{sub s} < 1 and is heavily damped for k{sub {theta}}{rho}{sub s} > 1. The predicted fluctuation level and transport coefficients are …
Date:
September 1, 1990
Creator:
Gang, F. Y.; Diamond, P. H. & Rosenbluth, M. N.
Object Type:
Report
System:
The UNT Digital Library
Recoil-range studies of heavy products of multinucleon transfer from /sup 18/O to /sup 245/Cm and /sup 249/Cf
Recoil range distributions were measured for alpha and spontaneous fission activities made in the bombardment of /sup 245/Cm and /sup 249/Cf with /sup 18/O from 6.20 MeV/nucleon down to the interaction barrier. The shape of the distributions indicates tht transfers of up to four protons take place via a combination of quasi-elastic (QET) and deep inelastic (DIT) mechanisms, rather than complete fusion-de-excitation (CF) or massive transfer (MT). Angular distributions constructed from recoil range distributions, assuming QET/DIT, indicate that the QET component contributes more significantly to the heavy product residue cross section than the DIT, even though primary cross sections are expected to be higher for DIT than for QET. This may be explained qualitatively as a result of the high excitation energies associated with DIT; the very negative Q/sub gg/ of projectile stripping for these systems combined with the lower expected optimal Q/sub rxn/ of QET compared to DIT can give QET products comparatively low excitation.
Date:
September 1, 1982
Creator:
McFarland, R.M.
Object Type:
Report
System:
The UNT Digital Library