scholarly journals TOTAL CROSS-SECTION FOR PHOTON–AXION CONVERSIONS IN EXTERNAL ELECTROMAGNETIC FIELD

2014 ◽  
Vol 29 (02) ◽  
pp. 1450011
Author(s):  
D. V. SOA ◽  
H. N. LONG ◽  
T. D. THAM
Keyword(s):  
Electromagnetic Field ◽  
Electromagnetic Fields ◽  
Cross Section ◽  
Cross Sections ◽  
External Electromagnetic Field ◽  
Wave Guide ◽  
Periodic Field ◽  
Total Cross Sections ◽  
Low Energies ◽  
External Electromagnetic Fields

We reconsider the conversion of the photon into axion in the external electromagnetic fields, namely in the static fields and in a periodic field of the wave guide. The total cross-sections for the conversion are evaluated in detail. The result shows that with strong strength of external electromagnetic fields, the cross-sections are large enough to measure the axion production. In the wave guide, there exists the resonant conversion at the low energies, in which the value of cross-sections is much enhanced.

ELECTROMAGNETIC DETECTION OF AXIONS IN A WAVE GUIDE

1998 ◽  
Vol 13 (11) ◽  
pp. 873-878 ◽  
Author(s):  
DANG VAN SOA
Keyword(s):  
Electromagnetic Field ◽  
Cross Sections ◽  
Differential Cross ◽  
External Electromagnetic Field ◽  
Wave Guide ◽  
Differential Cross Sections ◽  
Electromagnetic Detection

The conversion of photons into axions in a periodic external electromagnetic field, i.e. the TEm0 mode, is considered in details by using Feynman methods. The differential cross-sections are given. It is shown that the lowest mode gives the main contribution to the considered process.

Comparison of D–T and D– 3 He at low energies

1953 ◽  
Vol 218 (1134) ◽  
pp. 432-438 ◽  
Keyword(s):  
Angular Distribution ◽  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Coulomb Barrier ◽  
Simple Theory ◽  
Absolute Cross Section ◽  
Total Cross Sections ◽  
Gas Target ◽  
Low Energies

A thin gas target was used to measure the absolute cross-section and angular distribution of α -particles from the two ‘ mirror ’ reactions D– 3 H and D– 3 He for deuteron energies below 45 keV. The reactions were found to be isotropic and the variations of the total cross-sections over the energy range 20 to 45 keV can be expressed by the simple Gamow theory of penetration of the coulomb barrier. The simple theory assuming the same energy-independent nuclear parameters for the mirror nuclei 3 H and 3 He was unable to account for the observed cross-sections of these two reactions.

scholarly journals Odderon and pomeron as fractal dimension in pp and p̄p total cross-sections

2016 ◽  
Vol 31 (10) ◽  
pp. 1650066 ◽  
Author(s):  
F. S. Borcsik ◽  
S. D. Campos
Keyword(s):  
Fractal Dimension ◽  
Total Cross Section ◽  
Cross Section ◽  
Cross Sections ◽  
Fractal Dimensions ◽  
Total Cross Sections ◽  
High Energies ◽  
Fitting Procedure ◽  
Low Energies ◽  
Section Structure

In this paper, one presents a naive parametrization to [Formula: see text] and [Formula: see text] total cross-sections. The main goal of this parametrization is to study the possible fractal structure present in the total cross-section. The result of the fitting procedure shows two different fractal dimensions: a negative (low-energies) and a positive (high-energies). The negative fractal dimension represents the emptiness of the total cross-section structure and the positive represents the filling up process with the energy increase. Hence, the total cross-section presents a multifractal behavior. At low-energies, the odderon exchange may be associated with the negative fractal dimension and at high-energies, the pomeron may be associated with the positive fractal dimension. Therefore, the exchange of odderons and pomerons may be viewed as a transition from a less well-defined to a more well-defined internal structure, depending on the energy.

scholarly journals Radion Production in External Electromagnetic Field

2011 ◽  
Vol 21 (3) ◽  
pp. 193
Author(s):  
Phung Van Dong ◽  
Hoang Ngoc Long ◽  
Nguyen Huy Thao ◽  
Dang Van Soa ◽  
Nguyen Thi Hau
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Electric Field ◽  
Laboratory Experiment ◽  
Cross Sections ◽  
External Electromagnetic Field ◽  
Total Cross Sections ◽  
The Magnetic Field

A review of Randall-Sundrum model with stressing on radion phenomenology is presented. The radion production in the external electromagnetic field is considered. The total cross sections for the conversions in the presence of the electric field of the flat condenser as well as in the magnetic field of the solenoid are calculated in details. Based on our results a laboratory experiment for production and detection of the light radions may be described.

scholarly journals Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Roman N. Lee ◽  
Alexey A. Lyubyakin ◽  
Vyacheslav A. Stotsky
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Elliptic Integral ◽  
High Energy ◽  
Calculation Methods ◽  
Complete Elliptic Integral ◽  
Total Cross Sections ◽  
Multiloop Calculation ◽  
The Cross ◽  
Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

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.

PION-NUCLEON SCATTERING EXPERIMENTS AT LOW ENERGIES: π-p→π0n TOTAL CROSS SECTIONS

2005 ◽  
Vol 20 (08n09) ◽  
pp. 1818-1821
Author(s):  
J. BREITSCHOPF ◽  
M. BAUER ◽  
H. CLEMENT ◽  
M. CRÖNI ◽  
H. DENZ ◽  
...  
Keyword(s):  
Phase Shift ◽  
Cross Sections ◽  
Phase Shift Analysis ◽  
Single Charge ◽  
Charge Exchange Reaction ◽  
Total Cross Sections ◽  
Transmission Technique ◽  
Shift Analysis ◽  
Low Energies ◽  
Pion Nucleon

Total cross sections of the single charge exchange reaction π-p→π0n have been measured at PSI from about 40 to 250 MeV using a transmission technique. Preliminary results show an excellent agreement with predictions from the SAID FA02 phase shift analysis for energies above 70 MeV.

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.

Resonant production of electron-positron pairs by a hard gamma-ray on a nucleus in an external electromagnetic field

2020 ◽  
Vol 35 (03) ◽  
pp. 2040025 ◽  
Author(s):  
Nikita R. Larin ◽  
Victor V. Dubov ◽  
Sergei P. Roshchupkin
Keyword(s):  
Electromagnetic Field ◽  
Differential Cross Section ◽  
External Field ◽  
Cross Section ◽  
Differential Cross ◽  
Gamma Ray ◽  
Structure Constant ◽  
External Electromagnetic Field ◽  
Electron Positron ◽  
Resonant Production

The resonant production of electron-positron pairs by a hard gamma-ray on nucleus in an external electromagnetic field is studied theoretically. The main property of this process is that the initial process of the second order in the fine structure constant in an external field effectively splits into two successive processes of the first order due to the fact that in resonant conditions intermediate virtual electron (positron) becomes a real particle. One of these processes is a single-photoproduction of electron-positron pair in a laser field (laser-stimulated Breit-Wheeler process) another is a laser-assisted scattering of electron (positron) on nucleus (laser-assisted Mott scattering). It is shown that the resonances are possible only for the energies of the initial hard gamma-ray more than the characteristic threshold energy. Resonant differential cross section of this process is obtained. It is shown that the resonant differential cross section can significantly exceed the corresponding cross section without an external field. The obtained results may be experimentally verified using the facilities of pulsed laser radiation (SLAC, FAIR, XFEL, ELI, XCELS).

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