Excitation functions of pion reactions on $sup 14$N, $sup 16$O, and $sup 19$F through the (3,3) resonance

Journal Article · Sun Feb 01 04:00:00 EST 1976 · Phys. Rev., C, v. 13, no. 2, pp. 754-766

OSTI ID:4039940

Jacob, Jr, N P; Markowitz, S S

Cross sections for pion-induced reactions of the form ($pi$$,$$pi$N) and more complex spallation reactions of the form ($pi$,X) have been measured from 50- -550 MeV on the target nuclei $sup 14$N, $sup 16$O, and $sup 19$F using the secondary pion beams at the Lawrence Berkeley Laboratory 184-inch synchrocyclotron and the Clinton P. Anderson Meson Physics Facility. The dominance of the (3,3) free-particle resonance is seen in all excitation functions determined in this work. Relative to the $sup 12$C($pi$/sup plus-or- minus/,$pi$N)$sup 11$C reactions, the ($pi$/sup plus-or-minus/,$pi$N) reactions on $sup 14$N, $sup 16$O, and $sup 19$F have magnitudes of 0.2, 1, and 0.7, respectively. The cross section ratio R=sigma ($pi$$sup -$$,$$pi$$sup -$n)/sigma ($pi$$sup +$$,$$pi$ N) =1.68+-0.18 for $sup 14$N at 188+-15 MeV, 1.68+-0.05 for $sup 16$O at 188+-9 MeV, and 1.68+-0.03 for $sup 19$F at 178+-2 MeV incident pion energy. The results from this work are compared to previous pion work, analogous proton-induced reactions, Monte Carlo intranuclear cascade-evaporation calculations, and to a semiclassical nucleon charge-exchange model which convincingly explains the ($pi$$,$$pi$N) reaction mechanism in the (3,3) resonance region. (AIP)

• Research Organization: Lawrence Berkeley Laboratory and Department of Chemistry, University of California, Berkeley, California 94720
• NSA Number: NSA-33-024712
• OSTI ID: 4039940
• Journal Information: Phys. Rev., C, v. 13, no. 2, pp. 754-766, Journal Name: Phys. Rev., C, v. 13, no. 2, pp. 754-766; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

*FLUORINE 19 TARGET-- PION REACTIONS
*FLUORINE 19-- PION REACTIONS
*NITROGEN 14 TARGET-- PION REACTIONS
*NITROGEN 14-- PION REACTIONS
*OXYGEN 16 TARGET-- PION REACTIONS
*OXYGEN 16-- PION REACTIONS
*PION REACTIONS-- SPALLATION
642005*
CROSS SECTIONS
N68351* --Physics (Nuclear
Experimental)--Nuclear Properties & Reactions
6 <= A <= 19--Nuclear Reactions & Scattering
RESONANCE SCATTERING