PHOTONUCLEAR ACTIVATION BY 20 MEV GAMMA RAYS

Abstract

The photonuclear activation cross section of elements whose (gamma, n) reaction leads to a suitable positron activity was measured using monochromatic gamma rays from H-3(p, gamma)He-4 reaction. The gamma rays were monitored by a large sodium io ide cr stal whose response curve to the gamma rays was measured. The absorption coefficient of these photons in NaI was determined by a good geometry transmission experiment. The positron activity was determined by a coincidence detector, consisting of two 5-in.-diam by 2-in.long NaI crystals set on the annihilation radiation photopeaks. This detector was calibrated against a F-18 positron source, standardized in a 2 pi flow counter. The C-12(gamma, n)C-11 and F-19(g) activation cross section was measured at 20.5 Mev for Cr-50, Fe-54, Cu-63, Zn-64, Mo-92, Sb-121, Pr-141, and the results compared with those obtained with betatron experiments. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1961
Accession Number
AD0261124

Entities

People

  • Walter Del Bianco

Organizations

  • University of Pennsylvania

Tags

DTIC Thesaurus Topics

  • Absorption
  • Absorption Coefficients
  • Annihilation Radiation
  • Betatrons
  • Coefficients
  • Corpuscular Radiation
  • Detectors
  • Elementary Fermions
  • Elementary Particles
  • Fermions
  • Gamma Rays
  • Geometry
  • Ionizing Radiation
  • Nuclear Radiation
  • Positrons
  • Radiation

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Snow Cover Descriptors for Reptiles and Their Illustrations.
  • Solar Physics