High Energy Photons from Proton-Nucleon Collisions

Abstract

TWO-WEEK LOAN COpy. This is a Library Circulating Copy which may be borrowed for two weeks. For a personal retention copy. call Tech. Info. Diuision. Ext. 5545 BERKELEY, CALIFORNIA UCRL 439 Copy 2 DISCLAIMER This document was prepared as an account of work sponsored by the United States Government.

Early Particles

“…At the time I arrived in the summer of 1949, the cyclotron was operating with protons at 340 MeV, and there was a good deal of experimentation with pions, such as measurements of its mass and the determination of production cross sections of pions on different materials, chiefly using nuclear emulsions as detectors. Probably the most interesting experiment in progress was that of Bjorkland et al (14), which, in studying the spectra of gamma rays with a pair spectrometer, both forwards and backwards of a target hit by the internal proton beam, had found these spectra consistent with the postulate that they are the decay products of a neutral counterpart of the pion.…”

“…(Pief) Panofsky (famed for the beautiful experiments performed only months later on the production of neutral mesons where positive pions are absorbed in hydrogen, and for the development in the 1960s of the Stanford Linear Accelerator) and graduate student J. Steller to try, with similar technology, to detect the photons of a possible two-photon decay of a possible neutral pion, whose existence had already been indicated by the experiment of Bjorklund et al (14) in which single photons were detected from a target struck by protons in the cyclotron.…”

Ядерные Расщепления, Вызываемые Космическими Частицами Большой Энергии. III. Природа Ливневых Частиц

“…Исследования углового распределения ливневых частиц показали, что в нижней полусфере это распределение близко к изотропному 16 . Следова* тельно, с достаточной точностью можно считать, что распределение истинно изотропно и что это справедливо для протонов, дейтеро-нов и тритонов.…”

Coincidence measurements of the (. pi. /sup +/,. pi. /sup 0/p) reaction in the /triangle/-resonance region

“…Both of these reactions are SCX reactions as described by Eq. (1)(2)(3)(4)(5)(6)(7)(8). Because our measurements take place near the center of the A-resonance region, where the cross sections are overwhelmingly dominated by this resonance, the elementary SCX process must be the A-resonance as illustrated in Fig.…”