(p,pn) AND (p,2p) REACTIONS OF Ce$sup 142$ AT PROTON ENERGIES FROM 0.4 TO 3.0 Bev
Cross sections are reported for (p,pn) and (p,2p) reactions of Ce/sup 142/ with protons of 0.4, 1.0, 2.2, and 3.0 Bev. To evaluate the contribution of proton and neutron evaporrtion from excited Ce/sup 142/ nuclei to the observed cross sections, this evaporation competition was studied by means of cross- section measurements on the reactions Ba/sup 138/( alpha ,n) and Ba/sup 138/( alpha ,p) with a particles of 19- to 40-Mev kinetic energy. The ratio sigma / sub alpha ,n/ sigma /sub alpha ,p/ is between 2.4 and 4.4 in this region as compared with a ratio of 1.58 plus or minus 0.14 for sigma /sub p,pn/ sigma / sub p,2p/ at 0.4 Bev. It is concluded that at this energy the (p,pn) and (p,2p) reactions proceed at least partially by a pure knock-on mechanism. This conclusion is supported by comparison of the data with recent Monte Carlo calculations of intranuclear cascades. With increasing proton energy both sigma /sub p,2p/ and sigma /sub p,pn/ are found to decrease, the former more rapidly than the latter. This energy dependence is discussed in terms of the elementary nucleon-nucleon cross sections. The Monte Carlo calculations mertioned agree within their rather poor statistical accuracy with the measured cross-section ratios and with the energy dependence of the cross sections, but predict cross- section values about a factor of three too small. (auth)
- Research Organization:
- Brookhaven National Lab., Upton, N.Y.
- NSA Number:
- NSA-12-012791
- OSTI ID:
- 4299774
- Journal Information:
- Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 110; ISSN PHRVA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
EXCITATION FUNCTIONS OF THE (p,pn) AND (p,2p) REACTIONS ON Ce$sup 142$ AT 60-233 MEV
EXCITATION FUNCTIONS OF THE (p,pn) AND (p,2p) REACTIONS ON Te$sup 130$ AT 60-233 Mev