scholarly journals A Study of the 42Ca(p,?)43Sc Reaction

1977 ◽  
Vol 30 (4) ◽  
pp. 417 ◽  
Author(s):  
GU Din ◽  
B Heusch
Keyword(s):  
Excited States ◽  
Reasonable Agreement ◽  
Resonance Level ◽  
Angular Distributions ◽  
Proton Capture ◽  
Capture Reaction ◽  
Decay Properties ◽  
Theoretical Predictions ◽  
Bombarding Energy ◽  
First Time

The 42Ca(p, y)43SC reaction has been studied below 2�75 MeV proton bombarding energy. Approximately 100 resonances have been identified and located in the range Ep = 2�00-2�75 MeV. Nine resonances at Ep = 1045, 1201, 1299, 1319, 2038, 2471, 2523, 2643 and 2714 keV for the 42Ca(p, y)43SC reaction were investigated with either a 54 or a 120 cm3 Ge(Li) detector. Single spectra were obtained at each of these resonances, and these were used to derive consistent y ray decay schemes and accurate level energies for the resonant and bound levels of 43Sc. Fifty-two bound levels up to an excitation energy of 4�47 MeV were observed, out of which seventeen new levels have been identified at 2�114,2� 796,2' 846,2' 860,2' 875,3 '160,3' 331,3' 374,3 '463,3;504,3' 645, 3'734,3'757,3'860,4'007,4'038 and 4�430 MeV. In addition, new results or results differing from earlier reports have been obtained for the decay properties of levels below 4�47 MeV in 43SC? The strengths of the nine resonances were measured relative to the reported strength at Ep = 2038 keV. The resonance at Ep = 2643 keV was shown for the first time to populate levels of spin> 7/2 via the proton capture reaction. A strong M1 (analogue to anti-analogue) transition from the resonance level to the level at 1� 931 MeV (9/2+) was observed. From measurements of y ray angular distributions, the following spin and parity assignments were made: 9/2+ at 7'514, 7/2+ at 4'371, >7/2 at 4'038 and 7/2 at 3�808 MeV. The resonance level at 7�514 MeV has possibly aT = 3/2 character. The low-lying excited states in 43SC are in reasonable agreement with the theoretical predictions of Johnstone (1968).

scholarly journals 50Cr(p, g)51Mn Reaction from Ep = 1·45 to 2·07 MeV

1975 ◽  
Vol 28 (3) ◽  
pp. 263 ◽  
Author(s):  
GU Din ◽  
AM AI-Naser
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
Beam Direction ◽  
Proton Capture ◽  
Capture Reaction ◽  
Proton Resonances ◽  
First Time

Proton resonances in the SOCr(p, )1)51 Mn reaction have been studied in the range Ep = 1450-2070 keV. Gamma-ray spectra, measured at 55� to the beam direction at each of the resonances at Ep = 1451, 1546, 1580, 1600, 1689, 1798, 1830, 2031, 2042 and 2067 keV with a high resolution 35 cm3 Ge(Li) detector, have been used to derive the decay schemes of the resonant and bound levels in 51 Mn. Decays to the bound levels at 4'052, 4'729, 4'925, 5'073, 5'129, 5'174, 5'188, 5�203 and 5�506 MeV have been observed in the proton capture reaction for the first time, while new results have been obtained for the decay of some of these levels.

LIFETIME MEASUREMENTS OF EXCITED STATES IN 73As

2004 ◽  
Vol 13 (05) ◽  
pp. 1019-1034 ◽  
Author(s):  
K. P. SINGH ◽  
T. KAKAVAND ◽  
M. HAJIVALIEI
Keyword(s):  
Statistical Theory ◽  
Excited States ◽  
Doppler Shift ◽  
Nuclear Reactions ◽  
Angular Distributions ◽  
Excitation Energies ◽  
Lifetime Measurements ◽  
Mixing Ratios ◽  
Doppler Shift Attenuation ◽  
First Time

The excited states of 73 As have been investigated via the 73 Ge ( p , n γ)73 As reaction with proton beam energies from 2.5–4.3 MeV. The lifetimes of the levels at 769.6, 860.5, 1177.8, 1188.7, 1274.9, 1344.1, 1557.1 and 1975.2 keV excitation energies have been measured for the first time using the Doppler shift attenuation method. The angular distributions have been used to assign the spins and the multipole mixing ratios using statistical theory for compound nuclear reactions. The ambiguity in the spin values for the various levels has been removed. The multipole mixing ratios for eight γ-transitions have been newly measured.

scholarly journals Angular Distributions for 6Li(p,g)7Be

1987 ◽  
Vol 40 (3) ◽  
pp. 319 ◽  
Author(s):  
CIW Tingwell ◽  
JD King ◽  
DG Sargood
Keyword(s):  
Excited States ◽  
Angular Distributions ◽  
Substantial Agreement ◽  
Direct Capture ◽  
Theoretical Predictions

Angular distributions of y rays leading directly to the ground and first excited states in the reaction 6Li(p, y) 7Be have been measured at bombarding energies of 500, 800 and 1000 keV. The results are compared with those of previous measurements and substantial agreement is found. The results are also compared with theoretical predictions of a simple direct capture model.

EXCITED STATES OF 4He STUDIED WITH THE POLARIZED PROTON CAPTURE REACTION

1976 ◽  
pp. 266-270
Author(s):  
S.S. Hanna ◽  
H.F. Glavish ◽  
G. King ◽  
J.R. Calarco ◽  
D.G. Mavis ◽  
...  
Keyword(s):  
Excited States ◽  
Proton Capture ◽  
Capture Reaction ◽  
Polarized Proton

scholarly journals Proton-capture Reaction Cross Sections on the Sr Isotopes Relevant to the p-process Nucleosynthesis

2020 ◽  
Vol 13 ◽  
pp. 153
Author(s):  
S. Galanopoulos ◽  
S. Harissopulos ◽  
J. W. Hammer ◽  
R. Kunz ◽  
P. Demetriou
Keyword(s):  
Cross Sections ◽  
Reaction Cross ◽  
Tandem Accelerator ◽  
Proton Capture ◽  
Model Calculations ◽  
Capture Reaction ◽  
Level Densities ◽  
Theoretical Predictions ◽  
The University ◽  
Reaction Cross Sections

Proton-capture reaction cross sections on the 86,87,88Sr isotopes have been determined at energies from 1.4 to 5 MeV by measuring γ-angular distributions at the 4 MV single-ended Dynamitron accelerator of the University of Stuttgart as well as at the 5 MV VdG Tandem accelerator of NCSR "Demokritos", Athens. In the former case an array of 4 HPGe detectors with relative efficiency εr≈100%, each shielded with BGO crystals, were used. In the case of the measurements carried out at "Demokritos" we used only one HPGe detector (εr≈80%) with no BGO shield. Cross sections ranging from 0.5 μb to 5 mb as well as the relevant S factors were obtained. The data were compared with statistical model calculations using the code MOST. In the calculations, various combinations of microscopic and phe- nomenological models of the nucleon-Nucleus Optical Model Potentials (OMP) and Nuclear Level Densities (NLD) were used and a good agreement between the data and theoretical predictions was found.

scholarly journals Light Cluster Production in Central Symmetric Heavy-Ion Reactions from Fermi to Gev Energies

Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1406
Author(s):  
Rémi Bougault ◽  
Bernard Borderie ◽  
Abdelouahad Chbihi ◽  
Quentin Fable ◽  
John David Frankland ◽  
...  
Keyword(s):  
Equation Of State ◽  
Transport Model ◽  
Heavy Ion ◽  
Production Mechanism ◽  
State Information ◽  
Heavy Ion Reactions ◽  
Nuclear Equation Of State ◽  
Theoretical Predictions ◽  
Bombarding Energy ◽  
Deuteron Production

Correlations and clustering are of great importance in the study of the Nuclear Equation of State. Information on these items/aspects can be obtained using heavy-ion reactions which are described by dynamical theories. We propose a dataset that will be useful for improving the description of light cluster production in transport model approaches. The dataset combines published and new data and is presented in a form that allows direct comparison of the experiment with theoretical predictions. The dataset is ranging in bombarding energy from 32 to 1930 A MeV. In constructing this dataset, we put in evidence the existence of a change in the light cluster production mechanism that corresponds to a peak in deuteron production.

The interaction of atomic particles with solid surfaces at intermediate energies IV. The energy and angular distributions of particles scattered with electric charge from polycrystalline platinum at bombarding energies of 500-5000 eV

1974 ◽  
Vol 341 (1625) ◽  
pp. 213-231 ◽  
Keyword(s):  
Charged Particles ◽  
Solid Surfaces ◽  
Hydrogen Ion ◽  
Angular Distributions ◽  
Sodium Potassium ◽  
Intermediate Energies ◽  
Polycrystalline Platinum ◽  
Composite Spectra ◽  
Energy And Angular Distributions ◽  
Bombarding Energy

The distributions in angle and energy for charged particles emitted from polycrystalline platinum bombarded with ions of hydrogen, sodium, potassium and some hydrocarbons, have been measured, in continuation of previous work (Cawthron, Cotterell & Oliphant 1969 a , b , parts I and II; 1970, part III) to lower energies. Composite spectra are presented, including ions of both signs. The flux of emitted charged particles, under hydrogen ion bombardment, is shown to contain approximately equal numbers of protons and H¯ ions, except at the lowest bombarding energies, where the latter apparently predominate. Scattering in all cases is shown to increase with bombarding energy over the range covered, the increase being near linear for hydrogen and very rapid for alkalimetal ions. In all cases the total emission of charged particles is very small at the lowest bombarding energies employed.

scholarly journals Precision measurements on oxygen formation in stellar helium burning with gamma-ray beams and a Time Projection Chamber

2021 ◽  
Author(s):  
Robin Smith ◽  
Moshe Gai ◽  
Sarah Stern ◽  
Deran Schweitzer ◽  
Mohammad Ahmed
Keyword(s):  
Time Projection Chamber ◽  
Gamma Ray ◽  
Nuclear Reactions ◽  
Angular Distributions ◽  
Helium Burning ◽  
Low Energies ◽  
Important Input ◽  
Novel Method ◽  
Time Projection ◽  
First Time

Abstract Stellar Evolution theory relies on our knowledge of nuclear reactions, with the carbon/oxygen (C/O) ratio, at the end of helium burning, being the single most important input. However, the C/O ratio is still not known with sufficient accuracy, due to large uncertainties in the cross section for the fusion of helium with 12C to form 16O, denoted as the 12C(α,γ)16O reaction. We present initial results at moderately low energies using a novel method, which is significantly different from the experimental efforts of the past four decades. Precise angular distributions of the 12C(α,γ)16O reaction were obtained by measuring the inverse 16O(γ,α)12C reaction with gamma-beams and a Time Projection Chamber detector. These allowed us to measure, for the first time, the interference angle of the l = 1 and 2 partial waves contributing to this reaction (φ12), which agrees with predictions based on the unitarity of the scattering matrix.

scholarly journals Candidate name order effects in New Hampshire: Evidence from primaries and from general elections with party column ballots

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248049
Author(s):  
Bo MacInnis ◽  
Joanne M. Miller ◽  
Jon A. Krosnick ◽  
Clifton Below ◽  
Miriam Lindner
Keyword(s):  
New Hampshire ◽  
Political Engagement ◽  
Order Effects ◽  
Donald Trump ◽  
Major Party ◽  
Percentage Points ◽  
Theoretical Predictions ◽  
General Elections ◽  
Primacy Effects ◽  
First Time

Research in a few U.S. states has shown that candidates listed first on ballots gain extra votes as a result. This study explored name order effects for the first time in New Hampshire, where such effects might be weak or entirely absent because of high political engagement and the use of party column ballots. In general elections (in 2012 and 2016) for federal offices and the governorship and in primaries (in 2000, 2002, and 2004), evidence of primacy effects appeared in 86% of the 84 tests, including the 2016 presidential race, when Donald Trump gained 1.7 percentage points from first listing, and Hillary Clinton gained 1.5 percentage points. Consistent with theoretical predictions, primacy effects were larger in primaries and for major-party candidates in general elections than for non-major-party candidates in general elections, more pronounced in less publicized contests, and stronger in contests without an incumbent running. All of this constitutes evidence of the reliability and generalizability of evidence on candidate name order effects and their moderators.

On excited states of the Au3 cluster: an ab initio study

Open Physics ◽  
2008 ◽  
Vol 6 (4) ◽  
Author(s):  
Alexander Rusakov ◽  
André Zaitsevskii
Keyword(s):  
Excited States ◽  
Spectroscopic Data ◽  
Reasonable Agreement ◽  
Dipole Moments ◽  
Electronic States ◽  
Ab Initio Study ◽  
Many Body ◽  
Transition Energies ◽  
Vertical Transition ◽  
Theoretical Results

AbstractExcited electronic states of the Au3 cluster are studied within the shape-consistent small-core relativistic pseudopotential model using many-body multipartitioning perturbation theory. Vertical transition energies and dipole moments are evaluated. For highly symmetric isomer, these theoretical results are in reasonable agreement with spectroscopic data from experiments.

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