a{sub 0}{sup +} (980)-resonance production in the reaction pp {sup {yields}} d{pi}{sup +}{eta} close to the KK-bar threshold
The reaction pp {sup {yields}} d{pi}{sup +}{eta} has been measured at a beam energy of T{sub p} = 2.65 GeV (p{sub p} = 3.46 GeV/c) using the ANKE spectrometer at COSY-Julich. The missing-mass distribution of the detected d{pi}{sup +} pairs exhibits a peak around the {eta} mass on top of a strong bac...
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Published in | Physics of atomic nuclei Vol. 69; no. 2 |
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Main Authors | , , , , , , , , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
15.02.2006
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Subjects | |
Online Access | Get full text |
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Summary: | The reaction pp {sup {yields}} d{pi}{sup +}{eta} has been measured at a beam energy of T{sub p} = 2.65 GeV (p{sub p} = 3.46 GeV/c) using the ANKE spectrometer at COSY-Julich. The missing-mass distribution of the detected d{pi}{sup +} pairs exhibits a peak around the {eta} mass on top of a strong background of multipion pp {sup {yields}} d{pi}{sup +}(n{pi}) events. The differential cross section d{sup 4}{sigma}/d{omega}{sub d}d{omega}{sub {pi}}{sup +}dp{sub d}dp{sub {pi}}{sup +} for the reaction pp {sup {yields}} d{pi}{sup +}{eta} has been determined model independently for two regions of phase space. Employing a dynamical model for the a{sub 0}{sup +} production allows one then to deduce a total cross section of {sigma}(pp {sup {yields}} da{sub 0}{sup +} {sup {yields}} d{pi}{sup +}{eta}) = 1.1 {+-} 0.3{sub stat} {+-} 0.7{sub syst} {mu}b for the production of {pi}{sup +}{eta} via the scalar a{sub 0}{sup +}(980) resonance and {sigma}(pp {sup {yields}} d{pi}{sup +}{eta}) = 3.5 {+-} 0.3{sub stat} {+-} 1.0{sub syst} {mu}b for the nonresonant production. Using the same model as for the interpretation of recent results from ANKE for the reaction pp{yields}dK{sup +}K-bar{sup 0}, the ratio of the total cross sections is {sigma}(pp{yields}d(K{sup +}K-bar{sup 0}){sub L=0})/{sigma}(pp{yields}da{sub 0}{sup +}{yields}d{pi}{sup +}{eta})=0.029= {+-}0.008{sub stat}{+-}0.009{sub syst}, which is in agreement with branching ratios in the literature. |
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ISSN: | 1063-7788 1562-692X |
DOI: | 10.1134/S1063778806020153 |