scholarly journals Isomer ratios for the 88Sr(p,xn) and 88Sr(p,p3n) reactions

1967 ◽  
Vol 45 (22) ◽  
pp. 2711-2721 ◽  
Author(s):  
D. R. Sachdev ◽  
L. Yaffe
Keyword(s):  
Statistical Model ◽  
Spin Density ◽  
Cross Section ◽  
Experimental Results ◽  
Density Parameter ◽  
Model Calculations ◽  
Experimental Values ◽  
Parameter Values ◽  
Good Agreement

Isomeric cross-section ratios for nuclides formed from (p,2n), (p,3n), (p,4n), and (p,p3n) reactions on 88Sr are presented. The experimental results for the 88Sr(p,2n)87Ym,g reaction are compared with statistical-model calculations wherein spin-density parameter values were obtained from various theoretical formalisms. The parameters required to match the calculated and experimental values are in good agreement with those obtained by Vandenbosch et al.

scholarly journals The 7Be(p, ?)8B Cross Section at Low Energies

1980 ◽  
Vol 33 (2) ◽  
pp. 177 ◽  
Author(s):  
FC Barker
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Solar Neutrinos ◽  
Model Calculations ◽  
Spectroscopic Factors ◽  
Low Energies ◽  
Standard Values ◽  
Experimental Values ◽  
Parameter Values ◽  
Potential Parameters

The nonresonant part of the 7Be(p, )I)8B cross section at low energies is recalculated by means of a direct-capture potential model, using parameter values determined by fitting 7Li(n, n)7Li and 7Li(n, )I)8Li data. Standard values of the potential parameters and spectroscopic factors give values of the 7Li(n,)I) cross section that are too large. Modified values that fit the thermal-neutron capture cross section predict 7Be(p,)I) cross sections that are much less than the experimental values. Also, shell model calculations predict resonant 7Be(p,)I) cross sections that are smaller than the experimental values. It is suggested that the accepted experimental values of the 7Be(p, )I) cross section may be too large, perhaps due partly to an overlarge accepted value for the 7Li(d, p)8Li cross section, which has been used for normalization purposes. A decrease in the 7Be(p,)I) cross section would reduce the calculated detection rate of solar neutrinos and lessen the discrepancy with the measured value.

Photoalpha Reactions in the Region Z = 22 – 30

1972 ◽  
Vol 50 (13) ◽  
pp. 1554-1567 ◽  
Author(s):  
N. A. Keller ◽  
D. B. McConnell
Keyword(s):  
Statistical Model ◽  
Experimental Results ◽  
Angular Distributions ◽  
Model Calculations ◽  
Good Agreement

The yields and angular distributions of photoalphas from seven elements in the region Z = 22–30 were investigated experimentally. Strong anisotropies in the angular distributions from the even–even nuclei were observed. Improved statistical model calculations using the known spins and parities of the low lying levels of the even–even daughters give good agreement with the experimental results.

45Sc(p, p')45Sc and the Attainment of a Thermal Distribution of States in an Astrophysical Environment

1981 ◽  
Vol 34 (1) ◽  
pp. 105 ◽  
Author(s):  
MR Anderson ◽  
SR Kennett ◽  
ME Sevior ◽  
DG Sargood
Keyword(s):  
Statistical Model ◽  
Energy Range ◽  
Excited States ◽  
Cross Section ◽  
Cross Sections ◽  
Model Calculations ◽  
Thermal Distribution ◽  
Model Cross Section ◽  
Superelastic Scattering ◽  
Good Agreement

Cross sections for inelastic scattering of protons by 45SC have been measured over the energy range Ep = 1?2-2? 5 MeV for protons leading to the second, third, fourth, sixth and eighth excited states of 45SC. Statistical model calculations are' in good agreement with the data. Further statistical model cross section calculations are used in an investigation of the part played by inelastic and superelastic scattering of protons in bringing about a thermal distribution of states in 45SCin a stellar interior under the conditions of explosive silicon burning. This mechanism is found to be effective for temperatures above 4? ?x 109 K

scholarly journals Assessing the Instantaneous Stiffness of Cracked Reinforced Concrete Beams Based on a Gradual Change in Strain Distributions

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Chunyu Fu ◽  
Dawei Tong ◽  
Yuyang Wang
Keyword(s):  
Experimental Data ◽  
Reinforced Concrete ◽  
Cross Section ◽  
Concrete Beams ◽  
Internal Force ◽  
Experimental Results ◽  
Reinforced Concrete Beams ◽  
Gradual Change ◽  
Concrete Cracking ◽  
Good Agreement

Concrete cracking causes a gradual change in strain distributions along the cross section height of reinforced concrete beams, which will finally affect their instantaneous stiffness. A method for assessing the stiffness is proposed based on the gradual change, which is considered through modeling different strain distributions for key sections in cracked regions. Internal force equilibria are adopted to find a solution to top strains and neutral axes in the models, and then the inertias of the key sections are calculated to assess the beam stiffness. The proposed method has been validated using experimental results obtained from tests on five reinforced concrete beams. The predicted stiffness and displacements are shown to provide a good agreement with experimental data. The instantaneous stiffness is proven to greatly depend on the crack number and depth. This dependence can be exactly reflected by the proposed method through simulating the gradual change in concrete strain distributions.

Total-to-K-shell photoelectric cross-section ratios in some rare-earth and high-Z elements

1989 ◽  
Vol 67 (2-3) ◽  
pp. 139-142 ◽  
Author(s):  
S. Chandra Lingam ◽  
K. Suresh Babu ◽  
V. Prakash Kumar ◽  
D. V. Krishna Reddy
Keyword(s):  
Rare Earth ◽  
Cross Section ◽  
Atomic Number ◽  
Cross Sections ◽  
Cross Section Ratio ◽  
Section Ratio ◽  
Photoelectric Cross Section ◽  
Normal Transmission ◽  
Experimental Values ◽  
Good Agreement

The total photoelectric cross-sections in the elements gadolinium, dysprosium, erbium, lutetium, tantalum, tungsten, gold, and lead have been obtained by using the normal transmission experiments, and the results are reported. Using these total photoelectric cross sections, we have found the K-shell photoelectric cross sections, the K-jump ratios, and the total-to-K-shell photoelectric cross-section ratios at the K edges for the above elements. These values are compared with the available theoretical and experimental values. The results are in good agreement with the Storm and Israel results and the Scofield theoretical values, within the limits of experimental uncertainties. Furthermore, the variation of the total-to-K-shell photoelectric cross-section ratio with energy and atomic number is discussed.

PECULIARITIES OF NUCLEAR REACTIONS INDUCED BY 6He AND 6Li NUCLEI NEAR THE COULOMB BARRIER

2008 ◽  
Vol 17 (10) ◽  
pp. 2349-2353 ◽  
Author(s):  
YU. E. PENIONZHKEVICH ◽  
R. KALPAKCHIEVA ◽  
A. A. KULKO ◽  
S. M. LUKYANOV ◽  
V. A. MASLOV ◽  
...  
Keyword(s):  
Statistical Model ◽  
Cross Section ◽  
Coulomb Barrier ◽  
Nuclear Reactions ◽  
Transfer Reactions ◽  
Excitation Functions ◽  
Model Calculations ◽  
The Cross ◽  
Evaporation Residues

Excitation functions for evaporation residues in the reactions 206,208 Pb (6,4 He,2n 210 Po , as well as for the transfer reactions in the interaction of 6 He and 6 Li projectiles with Au and Pt were measured at the energies near the Coulomb barrier. Studied reactions were characterized by an increase in the cross-section compared to statistical model calculations.

scholarly journals Statistical model calculations of the 7Li +11 Β reaction

2019 ◽  
Vol 10 ◽  
pp. 165
Author(s):  
C. Tsabaris ◽  
C. T. Papadopoulos ◽  
R. Vlastou ◽  
A. A. Pakou ◽  
P. A. Assimakopoulos ◽  
...  
Keyword(s):  
Experimental Data ◽  
Statistical Model ◽  
Energy Range ◽  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Coulomb Barrier ◽  
Reaction Channel ◽  
Model Calculations ◽  
The Individual

The 7Li + 11 Β reaction has been studied in the energy range from a little below to about three times the Coulomb barrier by measuring the cross section of the 7- ray transitions in the residual nuclei produced. Statistical compound nucleus calculations have been performed in order to interpret the experimental data as well as to extract cross sections of the individual exit channels. The statistical compound nucleus theory can reproduce rather well the absolute j - ray and the various reaction channel excitation functions.

scholarly journals Isomeric cross section study of neutron induced reactions on Ge isotopes

2020 ◽  
Vol 239 ◽  
pp. 01028
Author(s):  
R. Vlastou ◽  
A. Kalamara ◽  
G. Gkatis ◽  
A. Stamatopoulos ◽  
M. Kokkoris ◽  
...  
Keyword(s):  
Statistical Model ◽  
Cross Section ◽  
Cross Sections ◽  
Residual Nucleus ◽  
Activation Technique ◽  
Flux Variation ◽  
Model Calculations ◽  
Neutron Beams ◽  
Hpge Detectors ◽  
Empire Code

Cross sections for the 70,76Ge(n,2n), 72,73Ge(n,p) and 72,74Ge(n, α) reactions have been measured at the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR Demokritos, using the activation technique. Neutron beams have been produced in the ~16-20 MeV energy region, by means of the 3H(d,n)4He reaction. The maximum flux has been determined to be of the order of 105 n/cm2 s, while the flux variation of the neutron beam was monitored by using a BF3 detector. The cross section has been deduced with respect to the 27Al(n, α)24Na and 93Nb(n,2n)92mNb reference reactions. The contaminations from reactions induced on neighboring Ge isotopes and leading to the same residual nucleus, have been taken into account. After the end of the irradiations, the activity induced by the neutron beams at the targets and reference foils, has been measured by HPGe detectors. Statistical model calculations using the EMPIRE code were performed on the data measured in this work as well as on data reported in literature.

Atomistic Simulation for the Site Preference of Tb3(Fe28-XCoX)V1.0 Compounds

2012 ◽  
Vol 535-537 ◽  
pp. 1015-1018
Author(s):  
Jing Sun ◽  
Shuo Huang ◽  
Jiang Shen ◽  
Ping Qian
Keyword(s):  
Rare Earth ◽  
Structural Properties ◽  
Atomistic Simulation ◽  
Experimental Results ◽  
Inversion Method ◽  
Site Preference ◽  
Lattice Constants ◽  
Pair Potentials ◽  
Experimental Values ◽  
Good Agreement

The effect of cobalt on the structural properties of intermetallic Tb3(Fe28-xCox)V1.0with Nd3(Fe,Ti)29structure has been studied by using interatomic pair potentials obtained through the lattice inversion method. Calculated results show that the order of site preference of cobalt is 8j(Fe8), 4e(Fe11) and 2c(Fe1) which is in good agreement with experimental results. And the calculated lattice constants coincide quite well with experimental values. All these prove the effectiveness of interatomic pair potentials obtained through the lattice inversion method in the description of rare-earth materials.

Theoretical Investigation of the Switching Mechanism in a Bistable Wall Attachment Fluid Amplifier

1971 ◽  
Vol 93 (1) ◽  
pp. 55-62 ◽  
Author(s):  
M. Epstein
Keyword(s):  
Theoretical Investigation ◽  
Experimental Results ◽  
Turbulent Jet ◽  
Switching Behavior ◽  
Switching Mechanism ◽  
Switching Times ◽  
Experimental Values ◽  
End Wall ◽  
Good Agreement

A theory based on turbulent jet entrainment properties is presented for the prediction of unsteady end wall switching behavior in a bistable wall attachment fluid amplifier. Good agreement is obtained between theoretically predicted switching times and experimental results. The analysis also indicates the experimentally observed dwell phenomena and computed dwell times compare well with reported experimental values.

Sign in / Sign up

Export Citation Format

Share Document