The two-body photodisintegration of (4)He into a proton and a triton has been studied using the CEBAF Large-Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. Real photons produced with the Hall-B bremsstrahlung-tagging system in the energy range from 0.35 to 1.55 GeV were incident on a liquid (4)He target. This is the first measurement of the photodisintegration of (4)He above 0.4 GeV. The differential cross sections for the gamma(4)He -> pt reaction were measured as a function of photon-beam energy and proton-scattering angle and are compared with the latest model calculations by J.-M. Laget. At 0.6-1.2 GeV, our data are in good agreement only with the calculations that include three-body mechanisms, thus confirming their importance. These results reinforce the conclusion of our previous study of the three-body breakup of (3)He that demonstrated the great importance of three-body mechanisms in the energy region 0.5-0.8 GeV.
Photodisintegration of 4He into p+t
PISANO, SILVIA;
2009-01-01
Abstract
The two-body photodisintegration of (4)He into a proton and a triton has been studied using the CEBAF Large-Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. Real photons produced with the Hall-B bremsstrahlung-tagging system in the energy range from 0.35 to 1.55 GeV were incident on a liquid (4)He target. This is the first measurement of the photodisintegration of (4)He above 0.4 GeV. The differential cross sections for the gamma(4)He -> pt reaction were measured as a function of photon-beam energy and proton-scattering angle and are compared with the latest model calculations by J.-M. Laget. At 0.6-1.2 GeV, our data are in good agreement only with the calculations that include three-body mechanisms, thus confirming their importance. These results reinforce the conclusion of our previous study of the three-body breakup of (3)He that demonstrated the great importance of three-body mechanisms in the energy region 0.5-0.8 GeV.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
