Angular distributions of protons from bremsstrahlung of maximum energy 400 MeV incident on elements between lithium and gold

Abstract

The cross-sections for photo-proton emission from Li, Be, C, O, AI, Ca, Cu, Ag and Au irradiated with bremsstrahlung of maximum energy 400 MeV have been determined for proton energies in the range 80 to 280 MeV at laboratory angles between 14 and 130 degrees. A qualitative examination of the data is made to determine whether or not they agree with the predictions of the quasi-deuteron model.

Cross-sections for deuteron photo-disintegration from 139 to 832 MeV

“…The first of the two hydrogen experiments was preceded by a long setting-up period during which we measured, among many other things, the cross-sections for photoproton emission from carbon. We found excellent agreement with data obtained earlier in this laboratory [18], with a different counter telescope, The discrepancies between our data and, e.g., the Bonn-Orsay set are most marked at lower proton energies. To check upon our understanding of the behaviour of our apparatus at proton energies below 100 MeV, Hammarstedt [19] has at our instigation built a total-absorption counter telescope and remeasured photo-proton cross-sections from carbon at 90 ~ laboratory.…”

“…To check upon our understanding of the behaviour of our apparatus at proton energies below 100 MeV, Hammarstedt [19] has at our instigation built a total-absorption counter telescope and remeasured photo-proton cross-sections from carbon at 90 ~ laboratory. Agreement with the range-telescope data of [18] was again satisfactory. It is clearly irrelevant that these tests were performed with carbon targets.…”

Photo-protons from high-energy bremsstrahlung

“…Recent results on the yields of high-energy photo-protons from both bremsstrahlung and monochromatic photons incident mainly on carbon are compared with calculations using the Gabriel-Alsmiller model of high-energy photo-induced reactions. Good agreement is found for photons of energies up to 600 MeV.Recently, extensive sets of data on the cross-sections for nuclei from lithium to gold to produce high-energy photo-protons have become available [1,2]. In [1], data at an end-point energy of 400 MeV were given, while in [2], proton yields mainly from carbon irradiated with bremsstrah~ungofend-point energies between 125 and 1000MeV were listed, as were some data obtained by a "'photon difference" method.…”

“…In [1], data at an end-point energy of 400 MeV were given, while in [2], proton yields mainly from carbon irradiated with bremsstrah~ungofend-point energies between 125 and 1000MeV were listed, as were some data obtained by a "'photon difference" method. Some of the results of [1] have been analyzed in [3], in terms of the "quasi-deuteron" model as formulated by Matthews [4] and of the intra-nuclear cascade model (PICA) of Gabriel and Alsmiller [5]. In this paper, analysis of the data in [1] and [2] is extended, using the latter model.…”

Photo-protons from beryllium irradiated with intermediate energy bremsstrahlung

“…In Figure 3, the results of calculations with L= 5.2 and 9.3 are also included, to show how the calculated values depend on L. From these fits (and those at other angles), it is concluded that the uncertainty in L is about one unit, so that L--7.2 • There is only one earlier PICA analysis of beryllium data, viz., of the 400 MeV data in [1], which are analyzed in [4]. There, the value of L was determined to be 5.2+_1.0, somewhat smaller than but not incompatible with that found here.…”