K{sup -}p{yields}{sigma}{sup 0}{pi}{sup 0} reaction at low energies in a chiral quark model

Journal Article · Wed Apr 15 04:00:00 EDT 2009 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.79.045202· OSTI ID:21293717

Xianhui, Zhong ^[1]; Qiang, Zhao ^[2]

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1. Department of Physics, Hunan Normal University, Changsha 410081 (China)
2. Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

A chiral quark-model approach is extended to the study of the KN scattering at low energies. The process K{sup -}p{yields}{sigma}{sup 0}{pi}{sup 0} at P{sub K} < or approx. 800 MeV/c (i.e., the center-of-mass energy W < or approx. 1.7 GeV) is investigated. This approach successfully describes the differential cross sections and total cross section with the roles of the low-lying {lambda} resonances in n=1 shells clarified. The {lambda}(1405)S{sub 01} dominates the reactions over the energy region considered here. Around P{sub K}{approx_equal}400 MeV/c, the {lambda}(1520)D{sub 03} is responsible for a strong resonant peak in the cross section. The {lambda}(1670)S{sub 01} has obvious contributions around P{sub K}=750 MeV/c, while the contribution of {lambda}(1690)D{sub 03} is less important in this energy region. The nonresonant background contributions, i.e., u channel and t channel, also play important roles in the explanation of the angular distributions due to amplitude interferences. The u channel turns out to have significant destructive interferences with the {lambda}(1405)S{sub 01} at the forward angles. In contrast, the t-channel K* exchange has a constructive interference at the forward angles, whereas it suppresses the cross sections slightly at the backward angles. In the t channel, the K* exchange is more dominant than the {kappa} exchange. Our analysis suggests that configuration mixing exists within the {lambda}(1405)S{sub 01} and {lambda}(1670)S{sub 01} and results in admixtures of the [70,{sup 2}1,1/2] and [70,{sup 2}8,1/2] configurations. The {lambda}(1405)S{sub 01} is dominated by [70,{sup 2}1,1/2], and {lambda}(1670)S{sub 01} by [70,{sup 2}8,1/2]. The mixing angle is also determined. The {lambda}(1520)D{sub 03} and {lambda}(1690)D{sub 03} are assigned as [70,{sup 2}1,3/2] and [70,{sup 2}8,3/2], respectively.

• OSTI ID: 21293717
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 4 Vol. 79; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
CENTER-OF-MASS SYSTEM
CHIRALITY
CONFIGURATION MIXING
DIFFERENTIAL CROSS SECTIONS
GEV RANGE
KAONS MINUS
LAMBDA-1405 BARYONS
LAMBDA-1520 BARYONS
LAMBDA-1670 BARYONS
LAMBDA-1690 BARYONS
MEV RANGE
QUARK MODEL
SCATTERING
T CHANNEL
TOTAL CROSS SECTIONS
U CHANNEL
WEINBERG ANGLE