Measured Coulomb corrections to the pair production cross sections of Ta and Bi

1981 ◽  
Vol 59 (7) ◽  
pp. 914-923 ◽  
Author(s):  
N. K. Sherman ◽  
G. M. Ewart
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
Form Factors ◽  
Photon Absorption ◽  
Coulomb Correction ◽  
Electron Pairs ◽  
Experimental Values ◽  
Semi Empirical ◽  
Coulomb Distortion

The cross sections for production of electron pairs on Ta and Bi nuclei by photons of energies between 3 and 30 MeV were deduced from total cross sections for photon absorption. Comparison with pair cross section values calculated in the plane-wave approximation and corrected for screening gave experimental values of the further correction required to account for Coulomb distortion. Above 15 MeV the experimental values of the Coulomb correction differ from values calculated using a semi-empirical recipe due to Maximon and Gimm, but agree fairly well with a recipe due to Øverbø up to 20 MeV, where they begin to differ. Either of these Coulomb correction formulas combined with screening corrections calculated using relativistic atomic form factors allows the pair cross section of Ta or Bi to be calculated accurately enough to reproduce the total photon cross section to about 1%. Neither formula can be relied upon to determine an unknown photonuclear cross section to useful accuracy from a measured total cross section.

scholarly journals MEASUREMENT OF 230Pa AND 186Re PRODUCTION CROSS SECTIONS INDUCED BY DEUTERONS AT ARRONAX FACILITY

2014 ◽  
Vol 27 ◽  
pp. 1460149
Author(s):  
CHARLOTTE DUCHEMIN ◽  
ARNAUD GUERTIN ◽  
VINCENT METIVIER ◽  
FERID HADDAD ◽  
NATHALIE MICHEL
Keyword(s):  
Targeted Therapy ◽  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
Decay Product ◽  
Targeted Radiotherapy ◽  
Stacked Foil Technique ◽  
Experimental Values ◽  
Foil Technique ◽  
Α Particles

A dedicated program has been launched on production of innovative radionuclides for PET imaging and for β- and α targeted radiotherapy using proton or α particles at the ARRONAX cyclotron. Since the accelerator is also able to deliver deuteron beams up to 35 MeV, we have reconsidered the possibility of using them to produce medical isotopes. Two isotopes dedicated to targeted therapy have been considered: 226Th, a decay product of 230Pa, and 186Re. The production cross sections of 230Pa and 186Re, as well as those of the contaminants created during the irradiation, have been determined by the stacked-foil technique using deuteron beams. Experimental values have been quantified using a referenced cross section. The measured cross sections have been used to determine expected production yields and compared with the calculated values obtained using the Talys code with default parameters.

scholarly journals Electron and Muon production cross-sections in quasielastic ν(ν̄)-Nucleus scattering for Eν < 1GeV

2015 ◽  
Vol 24 (11) ◽  
pp. 1550079 ◽  
Author(s):  
F. Akbar ◽  
M. Rafi Alam ◽  
M. Sajjad Athar ◽  
S. Chauhan ◽  
S. K. Singh ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
Form Factors ◽  
Reaction Cross ◽  
Nuclear Medium ◽  
Free Nucleon ◽  
Medium Effects ◽  
Muon Production ◽  
Nucleus Scattering

In this paper, we have studied (anti)neutrino induced charged current quasielastic (CCQE) scattering from some nuclear targets in the energy region of [Formula: see text]. Our aim is to confront electron and muon production cross-sections relevant for [Formula: see text] or [Formula: see text] oscillation experiments. The effects due to lepton mass and its kinematic implications, radiative corrections, second class currents (SCCs) and uncertainties in the axial and pseudoscalar form factors are calculated for (anti)neutrino induced reaction cross-sections on free nucleon as well as the nucleons bound in a nucleus where nuclear medium effects influence the cross-section. For the nuclear medium effects, we have taken some versions of Fermi gas model (FGM) available in the literature. The results for (anti)neutrino–nucleus scattering cross-section per interacting nucleons are compared with the corresponding results in free nucleon case.

Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

2019 ◽  
pp. 22-30
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Applied Load ◽  
Experimental Studies ◽  
Strength Properties ◽  
Research Topic ◽  
Normative Values ◽  
Laminated Glass ◽  
The Cross ◽  
Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

scholarly journals Collinear expansion for color singlet cross sections

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
Markus A. Ebert ◽  
Bernhard Mistlberger ◽  
Gherardo Vita
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
Gluon Fusion ◽  
Building Blocks ◽  
Color Singlet ◽  
Final State ◽  
Beam Function ◽  
Kinematic Limit ◽  
State Radiation

Abstract We demonstrate how to efficiently expand cross sections for color-singlet production at hadron colliders around the kinematic limit of all final state radiation being collinear to one of the incoming hadrons. This expansion is systematically improvable and applicable to a large class of physical observables. We demonstrate the viability of this technique by obtaining the first two terms in the collinear expansion of the rapidity distribution of the gluon fusion Higgs boson production cross section at next-to-next-to leading order (NNLO) in QCD perturbation theory. Furthermore, we illustrate how this technique is used to extract universal building blocks of scattering cross section like the N-jettiness and transverse momentum beam function at NNLO.

scholarly journals Charged current Drell-Yan production at N3LO

2020 ◽  
Vol 2020 (11) ◽  
Author(s):  
Claude Duhr ◽  
Falko Dulat ◽  
Bernhard Mistlberger
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Production Cross Section ◽  
Production Cross ◽  
Hadron Collider ◽  
Charge Asymmetry ◽  
Charged Current ◽  
Leading Order ◽  
Neutrino Pair ◽  
The Impact

Abstract We present the production cross section for a lepton-neutrino pair at the Large Hadron Collider computed at next-to-next-to-next-to-leading order (N3LO) in QCD perturbation theory. We compute the partonic coefficient functions of a virtual W± boson at this order. We then use these analytic functions to study the progression of the perturbative series in different observables. In particular, we investigate the impact of the newly obtained corrections on the inclusive production cross section of W± bosons, as well as on the ratios of the production cross sections for W+, W− and/or a virtual photon. Finally, we present N3LO predictions for the charge asymmetry at the LHC.

scholarly journals Temperature-Dependent Stimulated Emission Cross-Section in Nd3+:YLF Crystal

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 431
Author(s):  
Giorgio Turri ◽  
Scott Webster ◽  
Michael Bass ◽  
Alessandra Toncelli
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Room Temperature ◽  
Radiative Decay ◽  
Emission Cross Section ◽  
Spectroscopic Properties ◽  
Stimulated Emission ◽  
Different Temperatures ◽  
Stimulated Emission Cross Section ◽  
Semi Empirical

Spectroscopic properties of neodymium-doped yttrium lithium fluoride were measured at different temperatures from 35 K to 350 K in specimens with 1 at% Nd3+ concentration. The absorption spectrum was measured at room temperature from 400 to 900 nm. The decay dynamics of the 4F3/2 multiplet was investigated by measuring the fluorescence lifetime as a function of the sample temperature, and the radiative decay time was derived by extrapolation to 0 K. The stimulated-emission cross-sections of the transitions from the 4F3/2 to the 4I9/2, 4I11/2, and 4I13/2 levels were obtained from the fluorescence spectrum measured at different temperatures, using the Aull–Jenssen technique. The results show consistency with most results previously published at room temperature, extending them over a broader range of temperatures. A semi-empirical formula for the magnitude of the stimulated-emission cross-section as a function of temperature in the 250 K to 350 K temperature range, is presented for the most intense transitions to the 4I11/2 and 4I13/2 levels.

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.

scholarly journals Hadronic form factors and theJ/ψsecondary production cross section: An update

2005 ◽  
Vol 72 (2) ◽  
Author(s):  
F. Carvalho ◽  
F. O. Durães ◽  
F. S. Navarra ◽  
M. Nielsen
Keyword(s):  
Cross Section ◽  
Production Cross Section ◽  
Production Cross ◽  
Form Factors

scholarly journals Evaluation of the Compton (Incoherent) and Rayleigh (Coherent) Differential Cross Sections of Scattering for Rhodium 103Rh45 and Tantalum181Ta73 by Employing CSC model

2012 ◽  
Vol 9 (3) ◽  
pp. 554-558 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Differential Cross Section ◽  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Form Factors ◽  
Differential Cross Sections ◽  
The Cross

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.

A small-molecule with a large two-photon absorption cross-section serves as a membrane-permeable ribonucleic acid (RNA) probe for live cell imaging

2018 ◽  
Vol 42 (17) ◽  
pp. 14325-14331 ◽  
Author(s):  
Ruiqing Feng ◽  
Longlong Li ◽  
Bing Li ◽  
Jinhui Li ◽  
Dan Peng ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Live Cell Imaging ◽  
Plasma Membranes ◽  
Cell Imaging ◽  
Photon Absorption ◽  
Absorption Cross ◽  
High Permeability ◽  
Two Photon Absorption ◽  
Two Photon

DMI could light up the RNA of the nucleus and the cytoplasm in living systems, which not only exhibits larger two-photon absorption cross-sections (981 GM), but also displays high-permeability to plasma membranes of vigorous cells.

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