Near-threshold NN{yields}d{pi} reaction in chiral perturbation theory

Journal Article · Wed Feb 15 04:00:00 EST 2006 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PhysRevC.73.024002· OSTI ID:20771249

Gaardestig, A; Phillips, D R; Elster, Ch ^[1]

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1. Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)

The near-threshold np{yields}d{pi}{sup 0} cross section is calculated in chiral perturbation theory to next-to-leading order in the expansion parameter {radical}(Mm{sub {pi}})/{lambda}{sub {chi}}. At this order irreducible pion loops contribute to the relevant pion-production operator. Although their contribution to this operator is finite, considering initial- and final-state distortions produces a linear divergence in its matrix elements. We renormalize this divergence by introducing a counterterm, whose value we choose to reproduce the threshold np{yields}d{pi}{sup 0} cross section measured at TRIUMF. The energy dependence of this cross section is then predicted in chiral perturbation theory, being determined by the production of p-wave pions, and also by energy dependence in the amplitude for the production of s-wave pions. With an appropriate choice of the counterterm, the chiral prediction for this energy dependence converges well.

• OSTI ID: 20771249
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 2 Vol. 73; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
CHIRALITY
CROSS SECTIONS
DEUTERONS
ENERGY DEPENDENCE
MATRIX ELEMENTS
NUCLEON-NUCLEON INTERACTIONS
P WAVES
PARTICLE PRODUCTION
PERTURBATION THEORY
PIONS NEUTRAL
RENORMALIZATION
S WAVES