Search results for "Deute"
showing 10 items of 549 documents
Primary-residue production cross sections and kinetic energies in 1AGeV 208Pb on deuteron reactions
2002
Abstract The production cross sections and the kinematical properties of primary residual nuclei have been studied in the reaction 208 Pb(1 A GeV)+d. Isotopic distributions were measured for all elements from titanium ( Z =22) to lead ( Z =82). The measured kinematical properties of the residues were also used to disentangle the relevant reaction mechanisms, spallation–evaporation and spallation–fission. The fragment separator FRS at GSI, Darmstadt, was used to separate and identify the reaction products. The measured quantities are important for the design and planning of future radioactive-beam facilities and accelerator-driven systems. The measured data of the present work are comprehe…
Heavy-mesons exchange and the backward deuteron electrodisintegration
1992
Backward electrodisintegration of the deuteron is calculated using an exchange-current operator containing π, η, ρ, ω, δ, σ, andA1 exchanges. The deuteron and1S0np wave functions are derived from the Bonn OBEPs. For completeness, we introduced theA1-meson exchange into the OBEP's as well. As a consequence, the value ofD-state probabilityPD is increased by 0.2%–0.8%. The computed cross sections are compared with new data.
Dispersive approach to the nuclear compton amplitude and exchange effects
1981
We discuss the limitation of the standard approach to exchange current effects from photonuclear sum rules. We propose to look for an energy-independent contribution to the real part of the forward Compton-scattering amplitude below pion threshold. Experimental data on photonuclear cross-sections are used to calculate the real part of the amplitude, by means of an once-subtracted dispersion relation. The analysis is made for2H,7Li and9Be at energies varying between 50 and 150 MeV. A remarkably stable value ofK=0.60 is extracted for deuterium. For 1p shell nuclei, the main uncertainty is due to the lack of data above 300 MeV.
A Method for Measurements of the Total 2H(γ,π−)PP Cross Sections at Threshold
1979
In recent years measurements of the total cross section for the reactions 2H(γ,π+ nn) and 2H(γ,π0)2H close to the production threshold were performed1. For the 2H(γ,π−)pp reaction data of similar good quality doesn’t exist. In this paper a method is prescribed and the feasibility for the reaction 2H(γ,π−)pp is demonstrated. Figure 1 shows the principle: The photon beam hits a liquid or high pressured gas target of 2H. π− are created on the deuteron and stopped in the same target cell. The major part of the tt are captured π− are captured by deuterons via the reaction 2H(π−,n)n. The energy is shared equally by the two neutrons (En= 68.2 MeV). One of these monochromatic neutrons is detected b…
Antiproton annihilation at rest in liquid deuterium into π−π0π0pS
1994
With the Crystal Barrel detector, the final state π−π0π0pS at rest in liquid deuterium was measured for the first time. A preliminary partial-wave analysis was performed, which required two interesting features: besides the ρ(770), a second pole was needed in the ππP-wave and a narrow resonance in the ππS-wave, slightly above 1500 MeV/c2. With the same parametrization a high-statistics π+π−π0 data set could also be well described.
Contributions of internal nucleon structure to the nuclear charge and current operators
1983
The relativistic pair current and contributions of nucleon isobars are evaluated in the constituent-quark model. Isovector charge and isoscalar current contributions change substantially compared to previous calculations. The magnetic form factor of the deuteron and the charge form factors of3He and3H are modifed significantly and the previously predicted large differences in the form factors of3He and3H are considerably reduced.
Polarization Observables in Deuteron Electrodisintegration
1992
The electrodisintegration of the deuteron with polarized beam and target is investigated. The additional polarization form factors (inclusive reaction) and structure functions (exclusive reaction) are discussed. The sensitivity of these form factors and structure functions to the potential model, to meson and isobar degrees of freedom, and to electromagnetic form factors is studied in different kinematical regions.
Quasi-elastic neutrino reaction in deuterium
1972
In this paper the processv+d→μ−+p+p is studied in the framework of the impulse approximation, with or without using closure approximation. Final-state interactions are considered.
Three-Body Analysis of Incoherent Photoproduction of η Mesons on the Deuteron near Threshold
2003
The importance of three-body dynamics in the ηnp system in elastic and inelastic η-deuteron scattering as well as coherent and incoherent η photo-production on the deuteron in the energy region from threshold up to 30 MeV above has been investigated. It is shown that a restriction to first order rescattering with respect to the NN- and ηN-final state interactions, i.e., restriction to rescattering in the two-body subsystems, does not give a sufficiently accurate approximation to the s-wave reaction amplitude and that higher order terms, as described by the three-body dynamics give very substantial contributions.
Deuteron electrodisintegration near threshold at high momentum transfer
1983
Electrodisintegration of the deuteron near the break-up threshold is a particularly striking example of the existence of exchange currents (EC). While the conventional one-body current contribution grossly underestimates the experimental cross-section up to a momentum transfer of aboutq μ 2 =15 fm−2, the inclusion of EC—dominantly π-MEC—leads to a drastic increase in satisfactory agreement with experimental data up toq 2=9 fm−2.