A critical survey of experimental cross section data, comparison with nuclear model calculations and estimation of production yields of 77Br and 77Kr in no-carrier-added form via various nuclear processes

2011 ◽  
Vol 269 (10) ◽  
pp. 1121-1129 ◽  
Author(s):  
H.E. Hassan ◽  
S.M. Qaim
Keyword(s):  
Cross Section ◽  
Nuclear Model ◽  
Critical Survey ◽  
Cross Section Data ◽  
Model Calculations ◽  
Section Data ◽  
Experimental Cross ◽  
Data Comparison ◽  
Nuclear Processes ◽  
No Carrier Added

Projectile breakup effects in the fusion dynamics of 6,7Li +144,152Sm reactions around Coulomb barrier

2020 ◽  
Vol 29 (05) ◽  
pp. 2050029
Author(s):  
Manjeet Singh Gautam ◽  
Sukhvinder Duhan ◽  
Rishi Pal Chahal ◽  
Hitender Khatri ◽  
Suman B. Kuhar ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Coulomb Barrier ◽  
Incomplete Fusion ◽  
Complete Fusion ◽  
Cross Section Data ◽  
Suppression Factor ◽  
Model Calculations ◽  
Section Data ◽  
Breakup Channel

This work emphasized the role of the projectile breakup channel by studying the complete fusion (CF) and incomplete fusion (ICF) dynamics of [Formula: see text] reactions. The theoretical calculations for the chosen reactions have been done by opting for the coupled channel approach and the energy dependent Woods–Saxon potential (EDWSP) model. The below barrier fusion enhancements of the studied reactions are reasonably addressed by the outcomes of the adopted models, which in turn can be attributed to the couplings of nuclear structure degrees of freedom of the collision partners to their relative motion. In contrast, at above barrier energies, the CF cross-section data of the chosen reactions are found to be suppressed significantly when compared with the predictions made by using the present models. Interestingly, the fusion suppression factors of the given reactions can be minimized considerably with respect to the reported value when it is analyzed within the framework of the EDWSP model. For instance, in case of [Formula: see text] ([Formula: see text] reaction, the magnitude of fusion suppression factor is minimized up to 7% (13%) relative to the reported value whereas for [Formula: see text] ([Formula: see text] reaction, the fusion suppression factor is found to be less by 7% (8%) with reference to the reported value. Such suppression effects can be correlated with the low breakup threshold of alpha breakup channel associated with the loosely bound projectile. The projectiles being weakly bound systems split into two charged fragments and either of the breakup components is absorbed by the target resulting in the reduction of incoming flux going into fusion channel. The flux lost from the CF channel appears in the form of ICF yields. For [Formula: see text], total fusion (TF) cross-sections that are sum of CF and ICF cross-sections are also analyzed in conjunction with the EDWSP model and thus reasonably explained by the model calculations. In order to identify the ICF contribution, the ratio of ICF/TF cross-section data of [Formula: see text] reaction has been examined and thus properly addressed by using the EDWSP model. The presence of ICF component in TF cross-section clearly pointed out the breakup of projectile due to its loosely bound nature prior to the Coulomb barrier. Although ICF data of other systems are not available in the literature, a similar behavior is expected for ICF and TF data for [Formula: see text] and [Formula: see text] reactions.

K*(892)0Λ & K+Σ*(1385)- PHOTOPRODUCTION ON THE DEUTERON

2014 ◽  
Vol 26 ◽  
pp. 1460101 ◽  
Author(s):  
◽  
PAUL MATTIONE
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Experimental Cross Section ◽  
Differential Cross Sections ◽  
Cross Section Data ◽  
Jefferson Lab ◽  
Section Data ◽  
Experimental Cross ◽  
Using Data

Preliminary measurements of the differential cross sections of the γn → K*(892)0Λ and γn → K+Σ*(1385)- reactions are shown using data from the Jefferson Lab Hall B CLAS g13 experiment. No experimental cross section data have yet been published on the γn → K*(892)0Λ reaction, and the only published cross section data on the γn → K+Σ*(1385)- reaction are at forward angles, where t-channel K+ and K*+ exchanges are predicted to dominate. These data can be used to contribute to the search for the "missing" N* resonances, some of which are predicted to have non-negligible couplings to the excited strangeness channels.

scholarly journals The Neutron Facility at NCSR "Demokritos"- Implementation in the Case of the 232Th(n,2n) and 241Am(n,2n) Reactions

2020 ◽  
Vol 13 ◽  
pp. 136
Author(s):  
R. Vlastou ◽  
C. T. Papadopoulos ◽  
G. Perdikakis ◽  
M. Kokkoris ◽  
S. Kossionides ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Computer Code ◽  
Reaction Cross ◽  
Cross Section Data ◽  
Model Calculations ◽  
Section Data ◽  
Neutron Facility ◽  
Mev Protons ◽  
Reaction Cross Sections

In the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR "Demokritos" monoenergetic neutron beams can be produced in the energy ranges 120-650 keV, 4-11.5 MeV and 16-20.5 MeV by using the 7Li(p,n), 2H(d,n) and 3H(d,n) reactions, respectively. The corresponding beam energies and ions delivered by the accelerator, are 1.92-2.37 MeV protons, 0.8-9.6 MeV deuterons and 0.8-3.7 MeV deuterons, for the three reactions, respectively. Experimental results for neutron energies from threshold up to 11.5 MeV and at 17.1 MeV will be given for the 232Th(n,2n)231Th reaction, while for the 241 Am(n,2n)240 Am reaction, preliminary cross section data at 10.4, 10.6 and 17.1 MeV will be discussed. In the framework of the CERN n-TOF collaboration, the cross section of these reactions have been measured relative to the 197Au(n,2n)196Au, 27Al(n,a)24Na and 93Nb(n,2n) reaction cross sections, by using the activation method. In addition to the experimental work, theoretical Statistical model calculations are being carried out using the computer code STAPRE/F. The results are compared to the experimental data.

scholarly journals 8Be Level Properties from the Low-energy 7Li(p, γo)8Be Cross Section

1996 ◽  
Vol 49 (6) ◽  
pp. 1081 ◽  
Author(s):  
FC Barker
Keyword(s):  
Shell Model ◽  
Cross Section ◽  
Low Energy ◽  
Cross Section Data ◽  
Model Calculations ◽  
R Matrix ◽  
Section Data ◽  
Extensive Data

R-matrix fits to 7Li(p, γo)8Be cross section data for Ep ≤ 1500 keV give reduced width amplitudes of the 1+ levels of 8Be at 17.64 and 18.15 MeV having signs in agreement with shell model calculations, contrary to previous fits to less-extensive data.

scholarly journals Accurate determination of production data of the non-standard positron emitter 86Y via the 86Sr(p,n)-reaction

2020 ◽  
Vol 108 (9) ◽  
pp. 747-756
Author(s):  
M. Shuza Uddin ◽  
Bernhard Scholten ◽  
M. Shamsuzzhoha Basunia ◽  
Sandor Sudár ◽  
Stefan Spellerberg ◽  
...  
Keyword(s):  
Cross Section ◽  
Irradiation Time ◽  
Accurate Determination ◽  
Nuclear Model ◽  
Scale Production ◽  
Reaction Products ◽  
Cross Section Data ◽  
Section Data ◽  
Positron Emitter ◽  
The Cross

AbstractIn view of several significant discrepancies in the excitation function of the 86Sr(p,n)86g+xmY reaction which is the method of choice for the production of the non-standard positron emitter 86Y for theranostic application, we carried out a careful measurement of the cross sections of this reaction from its threshold up to 16.2 MeV at Forschungszentrum Jülich (FZJ) and from 14.3 to 24.5 MeV at LBNL. Thin samples of 96.4% enriched 86SrCO3 were prepared by sedimentation and, after irradiation with protons in a stacked-form, the induced radioactivity was measured by high-resolution γ-ray spectrometry. The projectile flux was determined by using the monitor reactions natCu(p,xn)62,63,65Zn and natTi(p,x)48V, and the calculated proton energy for each sample was verified by considering the ratios of two reaction products of different thresholds. The experimental cross section data obtained agreed well with the results of a nuclear model calculation based on the code TALYS. From the cross section data, the integral yield of 86Y was calculated. Over the optimum production energy range Ep = 14 → 7 MeV the yield of 86Y amounts to 291 MBq/μA for 1 h irradiation time. This value is appreciably lower than the previous literature values calculated from measured and evaluated excitation functions. It is, however, more compatible with the experimental yields of 86Y obtained in clinical scale production runs. The levels of the isotopic impurities 87mY, 87gY, and 88Y were also estimated and found to be <2% in sum.

Evaluation of nuclear reaction cross section data of proton and deuteron induced reactions on 75As, with particular emphasis on the production of 73Se

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nouman Amjed ◽  
M. Naveed Aslam ◽  
Mazhar Hussain ◽  
Syed M. Qaim
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Thick Target ◽  
Evaluation Methodology ◽  
Impurity Level ◽  
Nuclear Model ◽  
Cross Section Data ◽  
Section Data ◽  
Integral Yield

Abstract 75Se (T1/2 = 120 d), 73gSe (T1/2 = 7.1 h) and 72Se (T1/2 = 8.4 d) are important radioisotopes of selenium, being used in tracer studies, PET investigations and as a generator parent, respectively. Cross section data for the formation of those radionuclides in proton and deuteron induced reactions on 75As were critically analyzed up to about 70 MeV. A well-developed evaluation methodology was applied to generate the statistically fitted cross sections, based on the critically analyzed literature experimental data and the theoretical cross section values of three nuclear model codes ALICE-IPPE, TAYLS 1.9, and EMPIRE 3.2. Using the fitted cross sections the integral yield of each radionuclide was calculated. For the estimation of impurities, the integral yield of each radionuclide was compared with the yields of the other two radionuclides over a given energy region, and therefrom the energy range was suggested for the high purity production of each of the radionuclides 75Se, 73Se and 72Se. For production of the very important non-standard positron emitter 73Se via the 75As(p,3n)73Se reaction, the optimum energy range was deduced to be E p = 40 → 30 MeV, with a thick target yield of 1441 MBq/μAh and the 72,75Se impurity level of <0.1%.

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