Nuclear excitation by positron annihilation

T. Mukoyama, Sakae Shimizu

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

A new mode of positron annihilation has been investigated experimentally. In this annihilation process without emission of radiation, the excess energy liberated is given to the nucleus involved. The experimental evidence for this process was established by observing the conversion electrons from In115m, first excited level (335 keV, 12-), after irradiation of natural indium foils by positrons from the β+ decay of Na22. Using the experimental data obtained, we have attempted to evaluate the cross section for positrons having just the energy corresponding to that necessary to excite In115 from the ground state to an excited level which may decay to the isomeric level concerned. The experimental value of the cross section is found to be ∼10-24 cm2, while the theoretical value estimated by Present and Chen is ∼10-26 cm2. Possible reasons for this difference are discussed.

Original languageEnglish
Pages (from-to)95-99
Number of pages5
JournalPhysical Review C - Nuclear Physics
Volume5
Issue number1
DOIs
Publication statusPublished - 1972

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positron annihilation
positrons
excitation
cross sections
decay
indium
foils
irradiation
nuclei
ground state
energy
radiation
electrons

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Nuclear and High Energy Physics

Cite this

Nuclear excitation by positron annihilation. / Mukoyama, T.; Shimizu, Sakae.

In: Physical Review C - Nuclear Physics, Vol. 5, No. 1, 1972, p. 95-99.

Research output: Contribution to journalArticle

Mukoyama, T. ; Shimizu, Sakae. / Nuclear excitation by positron annihilation. In: Physical Review C - Nuclear Physics. 1972 ; Vol. 5, No. 1. pp. 95-99.
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