ترغب بنشر مسار تعليمي؟ اضغط هنا

Complete measurement of three-body photodisintegration of 3He for photon energies between 0.35 and 1.55 GeV

66   0   0.0 ( 0 )
 نشر من قبل Silvia Niccolai
 تاريخ النشر 2004
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

The three-body photodisintegration of 3He has been measured with the CLAS detector at Jefferson Lab, using tagged photons of energies between 0.35 GeV and 1.55 GeV. The large acceptance of the spectrometer allowed us for the first time to cover a wide momentum and angular range for the two outgoing protons. Three kinematic regions dominated by either two- or three-body contributions have been distinguished and analyzed. The measured cross sections have been compared with results of a theoretical model, which, in certain kinematic ranges, have been found to be in reasonable agreement with the data.



قيم البحث

اقرأ أيضاً

We have measured cross sections for the gamma+3He->p+d reaction at photon energies of 0.4 - 1.4 GeV and a center-of-mass angle of 90 deg. We observe dimensional scaling above 0.7 GeV at this center-of-mass angle. This is the first observation of dime nsional scaling in the photodisintegration of a nucleus heavier than the deuteron.
180 - Carlos Granados 2010
Large angle photodisintegration of two nucleons from the 3He nucleus is studied within the framework of the hard rescattering model (HRM). In the HRM the incoming photon is absorbed by one nucleons valence quark that then undergoes a hard rescatterin g reaction with a valence quark from the second nucleon producing two nucleons emerging at large transverse momentum . Parameter free cross sections for pp and pn break up channels are calculated through the input of experimental cross sections on pp and pn elastic scattering. The calculated cross section for pp breakup and its predicted energy dependency are in good agreement with recent experimental data. Predictions on spectator momentum distributions and helicity transfer are also presented.
We present an extensive overview of production cross sections and kinetic energies for the complete set of nuclides formed in the spallation of 136Xe by protons at the incident energy of 1 GeV per nucleon. The measurement was performed in inverse kin ematics at the FRagment Separator (GSI, Darmstadt). Slightly below the Businaro-Gallone point, 136Xe is the stable nuclide with the largest neutron excess. The kinematic data and cross sections collected in this work for the full nuclide production are a general benchmark for modelling the spallation process in a neutron-rich nuclear system, where fission is characterised by predominantly mass-asymmetric splits.
Spallation residues and fission fragments from 1A GeV 238U projectiles irradiating a liquid hydrogen target were investigated by using the FRagment Separator at GSI for magnetic selection of reaction products including ray-tracing, energy-loss and ti me-of-flight techniques. The longitudinal-momentum spectra of identified fragments were analysed, and evaporation residues and fission fragments could be separated. For 1385 nuclides, production cross-sections covering 3 orders of magnitude with a mean accuracy of 15%, velocities in the U-rest frame and kinetic energies were determined. In the reaction all elements from uranium to nitrogen were found, each with a large number of isotopes.
The reaction pp->{pp}_sgamma, where {pp}_s is a proton pair with an excitation energy E_{pp}<3 MeV, has been observed with the ANKE spectrometer at COSY-Juelich for proton beam energies of T_p=0.353, 0.500, and 0.550 GeV. This is equivalent to photod isintegration of a free 1S_0 diproton for photon energies Egamma ~ T_p/2. The differential cross sections measured for c.m. angles 0 deg.<theta_{pp}<20 deg. exhibit a steep increase with angle that is compatible with E1 and E2 multipole contributions. The ratio of the measured cross sections to those of np->dgamma is on the 10^{-3}-10^{-2} level. The increase of the pp->{pp}_sgamma cross section with T_p might reflect the influence of the Delta(1232) excitation.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا