Measurement of η′(958) formation in two-photon collisions at LEP1
The formation of the η′ in the reaction e+e−→e+e−η′→e+e−π+π−γ has been measured by the L3 detector at a centre-of-mass energy of 91 GeV. The radiative width of the η′ has been found to be <math><mtext>Γ</mtext><msub><mi></mi><mn>γγ</mn></msub><...
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| Autores principales: | , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
1998
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/80460 |
| Aporte de: |
| Sumario: | The formation of the η′ in the reaction e+e−→e+e−η′→e+e−π+π−γ has been measured by the L3 detector at a centre-of-mass energy of 91 GeV. The radiative width of the η′ has been found to be <math><mtext>Γ</mtext><msub><mi></mi><mn>γγ</mn></msub><mtext>=4.17±0.10</mtext><mtext>(stat.)</mtext><mtext>±0.27</mtext><mtext>(sys.)</mtext><mspace sp="0.4" width="2px" linebreak="nobreak" is="true"></mspace><mtext>keV</mtext></math>. The Q<sup>2</sup> dependence of the η′ formation cross section has been measured for <math><mtext>Q</mtext><msup><mi></mi><mn>2</mn></msup><mtext>≤10</mtext><mspace sp="0.4" width="2px" linebreak="nobreak" is="true"></mspace><mtext>GeV</mtext><msup><mi></mi><mn>2</mn></msup></math> and the η′ electromagnetic transition form factor has been determined. The form factor can be parametrised by a pole form with <math><mtext>Λ=0.900±0.046</mtext><mtext>(stat.)</mtext><mtext>±0.022</mtext><mtext>(sys.)</mtext><mspace sp="0.4" width="2px" linebreak="nobreak" is="true"></mspace><mtext>GeV</mtext></math>. It is also consistent with recent non-perturbative QCD calculations. |
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