The 98° differential cross sections for the reactions 13C(γ,n0)12C and 13C(γ,n1)12C

1977 ◽  
Vol 55 (19) ◽  
pp. 1704-1715 ◽  
Author(s):  
J. G. Woodworth ◽  
K. G. McNeill ◽  
J. W. Jury ◽  
P. D. Georgopulos ◽  
R. G. Johnson

The differential cross sections at 98° for the reactions 13C(γ,n0)12C and 13C(γ,n1)12C were measured over the range of 6.0 to 37.0 MeV and 10.5 to 35.5 MeV, respectively. The cross sections are compared with previous results on the same nucleus or results from the similar reaction 12C(p,γ0)13N. In the region of the so-called pygmy resonance (about 13.5 MeV) there are many sharp resonances which correspond very well with the level structure of 13C as deduced from several other studies using various reactions. For the full energy region studied, further evidence for the isospin splitting of the 13C photoneutron cross section is obtained. In comparison of the cross sections with recent theoretical results, general agreement is obtained. However, several details of this comparison are in disagreement; the implications of this disagreement are discussed.

2009 ◽  
Vol 24 (02n03) ◽  
pp. 450-453
Author(s):  
◽  
T. SKORODKO ◽  
M. BASHKANOV ◽  
D. BOGOSLOWSKY ◽  
H. CALÉN ◽  
...  

The two-pion production in pp-collisions has been investigated in exclusive measurements from threshold up to Tp = 1.36 GeV . Total and differential cross sections have been obtained for the channels pnπ+π0, ppπ+π-, ppπ0π0 and also nnπ+π+. For intermediate incident energies Tp > 1 GeV , i.e. in the region, which is beyond the Roper excitation but at the onset of ΔΔ excitation the total ppπ0π0 cross section falls behind theoretical predictions by as much as an order of magnitude near 1.2 GeV, whereas the nnπ+π+ cross section is a factor of five larger than predicted. A model-unconstrained isospin decompostion of the cross section points to a significant contribution of an isospin 3/2 resonance other than the Δ(1232). As a possible candidate the Δ(1600) is discussed.


2012 ◽  
Vol 9 (3) ◽  
pp. 554-558 ◽  
Author(s):  
Baghdad Science Journal

The differential cross section for the Rhodium and Tantalum has been calculated by using the Cross Section Calculations (CSC) in range of energy(1keV-1MeV) . This calculations based on the programming of the Klein-Nashina and Rayleigh Equations. Atomic form factors as well as the coherent functions in Fortran90 language Machine proved very fast an accurate results and the possibility of application of such model to obtain the total coefficient for any elements or compounds.


1973 ◽  
Vol 51 (20) ◽  
pp. 2197-2201 ◽  
Author(s):  
P. W. Martin ◽  
R. McFadden ◽  
B. L. White

The differential cross sections for 4.3 MeV neutrons elastically scattered from natural samples of U, Bi, and Pb have been measured at laboratory angles of 5, 10, and 15°. In the case of uranium, the data are consistent with calculations based on the nuclear optical model and known electromagnetic interactions. Less satisfactory agreement to the data is obtained in the cross section measurements for lead and bismuth.


2019 ◽  
Vol 24 ◽  
pp. 36
Author(s):  
M. Axiotis ◽  
A. Lagoyannis ◽  
S. Fazinić ◽  
S. Harrisopulos ◽  
M. Kokkoris ◽  
...  

The application of standard-less PIGE requires the a priori knowledge of the differential cross section of the reaction used for the quantification of each detected light element. Towards this end, a lot of datasets have been published the last few years from several laboratories around the world. The discrepancies found can be resolved by applying a rigorous benchmarking procedure through the measurement of thick target yields. Such a procedure is proposed in the present paper and is applied in the case of the 19F(p,p’γ)19F reaction.


2020 ◽  
Vol 2020 (10) ◽  
Author(s):  
M. Aaboud ◽  
◽  
G. Aad ◽  
B. Abbott ◽  
O. Abdinov ◽  
...  

Two additions impacting tables 3 and 4 in ref. [1] are presented in the following. No significant impact is found for other results or figures in ref. [1].


1973 ◽  
Vol 28 (10) ◽  
pp. 1642-1653
Author(s):  
G.-P. Raabe

Scattering processes of atoms, molecules and ions with two crossing electronic potentials may be treated in the Stueckelberg-Landau-Zener-(SLZ) model. In this paper the WKB-solutions for the radial wave functions, given by Stueckelberg are used to calculate differential cross sections. The effects on the cross sections are explained in a semiclassical picture, following the procedures of Ford and Wheeler, and Berry. In the scattering of H+ by rare gases, some effects in the elastic cross sections are observed which can be explained by the influence of the potential of the chargeexchanged particles, using the SLZ-model. The structure in the elastic cross sections for H2+-Kr can be explained as a rainbow structure with superimposed Stueckelberg oscillations.


Differential cross-sections have been measured for the scattering of photons of mean energy 87 MeV by uranium at eight angles in the range from 1.18 to 4.48 mrad and by aluminium, silver, tungsten, lead and uranium at angles of 1.89 and 4.24 mrad, using a narrowly collimated bremsstrahlung beam from the Oxford 110 MeV synchrotron as the primary source of photons. A biased total-absorption Čerenkov counter was used to detect photons with energies near the peak energy of the bremsstrahlung spectrum, and absolute differential cross-sections were measured by comparing counting rates for photons in the primary and scattered beams. The experimental results, with the differential Compton scattering cross-sections of Klein and Nishina subtracted, were analyzed in terms of their variation with angle and atomic number, and can be described as consisting of a sharply peaked angular distribution with absolute cross-sections varying from element to element as Z 4 , together with a uniform distribution varying nearly as Z 2 ; these distributions were identified with Delbruck scattering and with bremsstrahlung from secondary electrons in the scattering target, respectively. The Delbruck scattering cross-section thus determined is slightly more sharply peaked than the cross-section predicted by an approximate theory of Bethe & Rohrlich.


1990 ◽  
Vol 10 (5-6) ◽  
pp. 319-332 ◽  
Author(s):  
N. Billy ◽  
B. Girard ◽  
G. Gouédard ◽  
J. Vigué

Differential cross sections can be measured as a function of the internal state of a reaction product thanks to the analysis of the Doppler profile of the laser induced fluorescence detection line. This analysis is complicated by two effects: first, the LIF signal intensity depends on the interaction time of the molecule with the laser, and this time depends on the scattering angle, second, the angular and velocity distributions of the beams have non negligible widths. We present here a treatment of these effects in the case of the F+I2 reaction for which we have measured the differential cross section by this technique. The same formalism is also applied to the deduction of the rovibrational distribution of the products from the relative intensities of the LIF lines.


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