Accession Number : AD0618660

Title :   ETA PHOTOPRODUCTION IN THE REGION FROM THRESHOLD TO 900 MEV,

Corporate Author : STANFORD UNIV CALIF HIGH ENERGY PHYSICS LAB

Personal Author(s) : Prepost,R. ; Lundquist,D. ; Quinn,D.

Report Date : MAY 1965

Pagination or Media Count : 16

Abstract : Measurements of the differential cross section of the process gamma + p to eta (o) + p were made in approximately 50 MeV intervals from threshold to 900 MeV. The yield of recoil protons is measured at a fixed momentum and angle as a function of the bremsstrahlung end point energy, and eta production is seen as a step in the proton yield at the appropriate threshold energy. The differential cross section at 90 degrees is characterized by a sharp rise near threshold reaching a maximum value of 1 microbarn/sr at 760 MeV, and then falling off to a value of 0.3 microbarn/sr at 900 MeV. A measurement of the differential cross section for 3 different angles at 790 MeV indicates that the cross section is isotropic in the center of mass at this energy. The interpretation of these results in terms of possible contributing partial waves will be discussed. (Author)

Descriptors :   (*GAMMA PROTON REACTIONS, DIFFERENTIAL CROSS SECTIONS), BREMSSTRAHLUNG, PIONS, PHOTONUCLEAR REACTIONS

Distribution Statement : APPROVED FOR PUBLIC RELEASE