31 research outputs found
Incoherent pion photoproduction on the deuteron in the first resonance region
Incoherent pion photoproduction on the deuteron is studied in the first
resonance region. The unpolarized cross section, the beam asymmetry, and the
vector and tensor target asymmetries are calculated in the framework of a
diagrammatic approach. Pole diagrams and one-loop diagrams with scattering
in the final state are taken into account. An elementary operator for pion
photoproduction on the nucleon is taken in various on-shell forms and
calculated using the SAID and MAID multipole analyses. Model dependence of the
obtained results is discussed in some detail. A comparison with predictions of
other works is given. Although a reasonable description of many available
experimental data on the unpolarized total and differential cross sections and
photon asymmetry has been achieved, in some cases a significant disagreement
between the theory and experiment has been found. Invoking known information on
the reactions and we predict the total
photoabsorption cross section for deuterium. We find that our values strongly
overestimate experimental data in the vicinity of the peak.Comment: 22 pages, 23 figure
Measurement of tensor analyzing powers in deuteron photodisintegration
New accurate measurement of tensor analyzing powers T20, T21 and T22 in
deuteron photodisintegration has been performed. Wide-aperture non-magnetic
detectors allowed to cover broad kinematic ranges in a single setup: photon
energy = 25 to 600 MeV, proton emission angle in CM = 24 to 48 deg. and 70 to
102 deg. New data provide a significant improvement of a few existing
measurements. The angular dependency of the tensor asymmetries in deuteron
photodisintegration is extracted for the first time.Comment: 4 pages, 5 figures, submitted to Phys. Rev. Let
Influence of the re-scattering process on polarization observables in reaction gamma + d --> p + p + pi- in Delta - resonance region
Influence of the effects of the pion-nucleon and nucleon-nucleon
re-scattering on the polarization observables of the reaction gamma + d = p + p
+ pi- in Delta - isobar region is investigated. Pion-nucleon and
nucleon-nucleon re-scattering are studied in the diagrammatic approach.
Relativistic-invariant forms of the pion photoproduction and pion-nucleon
scattering operators are used. The unitarization procedure in K-matrix approach
is applied for the resonance partial amplitudes. It is shown a considerable
influence of the re-scattering effects on the polarization observables of this
reaction in the Delta - resonance region for the large momenta of the final
protons.Comment: 16 pages, 5 Postscript figure
Status of the T20 experiment at VEPPâ3
Using a gaseous polarized deuterium and the 2 GeV electron beam at 2 GeV beam energy the tensor analyzing power, T20, for the NN potential will be measured with the elastic dâ(e,e) reaction at VEPPâ3, Novosibirsk. A description and progress report of the experiment is given. (AIP)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87524/2/530_1.pd
Electron scattering from polarized deuterium at VEPPâ3
The status, results, and future plans for the experiment measuring the tensor analyzing power of the deuteron using a tensorâpolarized internal target at the VEPPâ3 electron storage ring in Novosibirsk are presented. © 1995 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87517/2/713_1.pd