THE CAPTURE OF PROTONS BY DEUTERONS

1962 ◽  
Vol 40 (4) ◽  
pp. 402-411 ◽  
Author(s):  
G. M. Griffiths ◽  
E. A. Larson ◽  
L. P. Robertson
Keyword(s):  
Angular Distribution ◽  
Total Cross Section ◽  
Energy Dependence ◽  
Cross Section ◽  
Gamma Rays ◽  
Proton Energy ◽  
P Wave ◽  
S Wave ◽  
Proton Capture ◽  
The Cross

The cross section and angular distribution of gamma rays for the reaction D(p,γ)He3 have been measured for proton energies from 275 kev to 1.75 Mev. For 275-kev protons the total cross section is 0.97 ± 0.11 microbarns and for 985-kev protons it is 3.5 ± 0.38 microbarns. The angular distribution has the form (sin2θ+b) where b is small. b is found to increase with decreasing proton energy, contrary to some previous results from this laboratory, and the energy dependence of b and of the cross section suggests that the sin2 θ part of the cross section is due to the capture of p-wave protons and the b part is due to s-wave proton capture.

The cross-section and angular distribution of the D-D reactions below 50 keV

1953 ◽  
Vol 216 (1124) ◽  
pp. 57-65 ◽  
Keyword(s):  
Angular Distribution ◽  
Total Cross Section ◽  
Cross Section ◽  
Proportional Counter ◽  
Angular Distributions ◽  
Asymmetry Coefficient ◽  
Gas Target ◽  
The Asymmetry ◽  
The Cross ◽  
Bombarding Energy

A thin gas target was used and the particles from the reactions were detected by a proportional counter. The results show that the total cross-section for the two reactions is the same to within 1%, but that the angular distributions of the products are significantly different. The asymmetry coefficient for the reaction D( d , n ) 3 He is given by 0·31 + 0·0058 E , compared with 0·13 + 0·0047 E for reaction D( d , p ) 3 H, where E is the bombarding energy in kilovolts.

scholarly journals Experimental Study of the Astrophysically Interesting 112Cd(p,γ)113In Reaction

2019 ◽  
Vol 21 ◽  
pp. 188
Author(s):  
E.-M. Asimakopoulou ◽  
E. Malami ◽  
T. J. Mertzimekis ◽  
V. Foteinou
Keyword(s):  
Experimental Study ◽  
Angular Distribution ◽  
Statistical Model ◽  
Total Cross Section ◽  
Cross Section ◽  
Proton Capture ◽  
High Importance ◽  
Validity Test ◽  
Low Energies ◽  
Excited Nuclei

An experimental study of the astrophysically interesting 112Cd(p,γ)113In reaction, conducted at INPP, NCSR “Demokritos”, is presented. The purpose of the experiment was to study the total cross section and the angular distribution of the de-excited nuclei. The experiment aimed at both gaining knowledge of proton capture at low energies and serving as a validity test for the Hauser–Feshbach theory, a statistical model of compound reactions of high importance. Both in–beam and activation techniques were used during the experiment and the results are compared to TALYS calculations.

scholarly journals The Interaction of Neutrons with 7Be at BBN Temperatures: Lack of Standard Nuclear Solution to the “Primordial 7Li Problem”

2020 ◽  
Vol 227 ◽  
pp. 01007 ◽  
Author(s):  
M. Gai ◽  
E.E. Kading ◽  
M. Hass ◽  
K.M. Nollett ◽  
S.R. Stern ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
High Energy ◽  
Big Bang ◽  
Alpha Particles ◽  
P Wave ◽  
Recent Measurement ◽  
S Wave ◽  
Big Bang Nucleosynthesis ◽  
The Cross

We report the first measurement of alpha-particles from the interaction of neutrons with 7Be at “temperatures” of Big Bang Nucleosynthesis (BBN). We measured the Maxwellian averaged cross sections (MACS), with neutron beams produced by the LiLiT at the SARAF in Israel (with kT = 49.5 keV hence 0.57 GK). In addition, we measured the cross section of the 7Be(n,p) reaction, which is in excellent agreement with the recent measurement of the n_TOF collaboration, further substantiating our method as a demonstration of “proof of principle”. The cross section for the 7Be(n,ga) and the 7Be(n,a) reaction measured in the “BBN window” is considerably smaller than compiled by Wagoner in 1969 and used today in Big Bang Nucleosynthesis (BBN). We also rule out a hitherto unknown resonance in 8Be at the BBN window, that was conjectured as a possible standard nuclear physics solution to the “Primordial 7Li Problem”. Together with previous results, we deduce a new Wagoner-like Rate for the destruction of 7Be by neutrons which is based on all current measured data. We conclude the lack of a standard nuclear solution to the “Primordial 7Li Problem”. Our upper limit on the cross sections for the high energy alpha-particles is in agreement with recent measurement of the n_TOF collaboration, but it is considerably smaller than the p-wave extrapolation of the Kyoto collaboration. We measured the alpha-particles from the 7Be(n,gi)8Be*(3.03 MeV) reaction, which is considerably larger than a previous s-wave estimate. Hence, in contrast, we conclude s-wave dominance at BBN energies, as would be expected due to the broad (122 keV) low lying 2” state at En = 10 keV.

scholarly journals Discussion on the Theoretical Basis for Cross-Over Method Applied to Downhole Wave Velocity Test

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Qing Dong ◽  
Zheng-hua Zhou ◽  
Su Jie ◽  
Bing Hao ◽  
Yuan-dong Li
Keyword(s):  
Numerical Simulation ◽  
Numerical Simulations ◽  
Wave Velocity ◽  
Theoretical Basis ◽  
Influence Factors ◽  
P Wave ◽  
Engineering Practice ◽  
S Wave ◽  
Simulation Results ◽  
The Cross

At engineering practice, the theoretical basis for the cross-over method, used to obtain shear wave arrival time in the downhole method of the wave velocity test by surface forward and backward strike, is that the polarity of P-wave keeps the same, while the polarity of S-wave transforms when the direction of strike inverted. However, the characteristics of signals recorded in tests are often found to conflict with this theoretical basis for the cross-over method, namely, the polarity of the P-wave also transforms under the action of surface forward and backward strike. Therefore, 3D finite element numerical simulations were conducted to study the validity of the theoretical basis for the cross-over method. The results show that both shear and compression waves are observed to be in 180° phase difference between horizontal signal traces, consistent with the direction of excitation generated by reversed impulse. Furthermore, numerical simulation results prove to be reliable by the analytic solution; it shows that the theoretical basis for the cross-over method applied to the downhole wave velocity test is improper. In meanwhile, numerical simulations reveal the factors (inclining excitation, geophone deflection, inclination, and background noise) that may cause the polarity of the P-wave not to reverse under surface forward and backward strike. Then, as to reduce the influence factors, we propose a method for the downhole wave velocity test under surface strike, the time difference of arrival is based between source peak and response peak, and numerical simulation results show that the S-wave velocity by this method is close to the theoretical S-wave velocity of soil.

scholarly journals p-Wave Strength in the Low-energy 7Li(p,?0)8Be Cross Section

1995 ◽  
Vol 48 (5) ◽  
pp. 813 ◽  
Author(s):  
FC Barker
Keyword(s):  
Angular Distribution ◽  
Shell Model ◽  
Cross Section ◽  
Low Energy ◽  
P Wave ◽  
Model Calculations ◽  
Energy Data

Recent fits to low-energy 7Li(p, "Yo)8Be angular distribution and analysing power data suggested a large p-wave strength. It is shown that acceptable fits to the data can be obtained by attributing the p-wave Ml contributions to the tails of the 17 �64 and 18 �15 MeV 1+ levels of 8Be, with p-wave strengths much less than those obtained previously, but only if some of the spectroscopic amplitudes have signs opposite to those suggested by shell model calculations and/or a fit to higher-energy data.

DOUBLE PION PHOTOPRODUCTION EXPERIMENT AT LNS–TOHOKU

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2313-2316 ◽  
Author(s):  
◽  
H. KANDA ◽  
N. CHIGA ◽  
Y. FUJII ◽  
K. FUTATSUKAWA ◽  
...  
Keyword(s):  
Total Cross Section ◽  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Pion Photoproduction ◽  
Total Cross Sections ◽  
Free Proton ◽  
Double Pion ◽  
The Cross

The total cross sections for the π+π− photoproduction on the deuteron were measured in an energy range of 0.8 to 1.1 GeV. The obtained total cross section for the quasi-free π+π− photoproduction on the deuteron was about 60 % of those on the free proton. The cross section for Δ++Δ− photoproduction was derived from the non-quasi-free π+π− photoproduction events. It was smaller than the previous data.

scholarly journals Quasielastic Lepton Scattering off Two-Component Dark Matter in Hypercolor Model

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 708 ◽  
Author(s):  
Vitaly Beylin ◽  
Maxim Bezuglov ◽  
Vladimir Kuksa ◽  
Egor Tretiakov
Keyword(s):  
Dark Matter ◽  
Total Cross Section ◽  
Cross Section ◽  
Strong Dependence ◽  
Cosmic Ray ◽  
High Energy ◽  
Dominant Contribution ◽  
Quasielastic Scattering ◽  
Two Component ◽  
The Cross

The interaction of high-energy leptons with components of Dark Matter in a hypercolor model is considered. The possibility of detection, using IceCube secondary neutrinos produced by quasielastic scattering of cosmic ray electrons off hidden mass particles, is investigated. The dominant contribution to the cross section results from diagrams with scalar exchanges. A strong dependence of the total cross section on the Dark Matter components mass is also found.

Experimental study of the energy dependence of the total cross section for the 6He + natSi and 9Li + natSi reactions

2017 ◽  
Vol 48 (6) ◽  
pp. 922-926 ◽  
Author(s):  
Yu. G. Sobolev ◽  
Yu. E. Penionzhkevich ◽  
D. Aznabaev ◽  
E. V. Zemlyanaya ◽  
M. P. Ivanov ◽  
...  
Keyword(s):  
Experimental Study ◽  
Total Cross Section ◽  
Energy Dependence ◽  
Cross Section

Measurement of the translational energy dependence of the cross section for the reaction of Sr+CH3I→SrI+CH3 from 0.1 – 1.0 eV

1991 ◽  
Vol 176 (6) ◽  
pp. 499-503 ◽  
Author(s):  
Qi-Xun Xu ◽  
R. Scott Mackay ◽  
F.J. Aoiz ◽  
Mark A. Quesada ◽  
Patrick J. Grunberg ◽  
...  
Keyword(s):  
Energy Dependence ◽  
Cross Section ◽  
Translational Energy ◽  
The Cross
Sign in / Sign up

Export Citation Format

Share Document