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Role of pentaquark components into f meson production proton-antiproton annihilation reactions. Sorakrai Srisuphaphon. Outline. Introduction The proton wave functions with pentaquark component The transition amplitude for f meson production in proton-antiproton annihilation reactions
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Role of pentaquark components into f meson production proton-antiproton annihilation reactions SorakraiSrisuphaphon
Outline • Introduction • The proton wave functions with pentaquark component • The transition amplitude for f meson production in proton-antiproton annihilation reactions • Results and Conclusions
u u d proton Introduction Baryons being bound states of three quarks. The proton might contain a substantial strange quark-antiquark component Deep Inelastic Scattering The non-zero strange spin of the proton The strangeness magnetic moment can be extrapolated from the strange magnetic form factor Several experimental measurements suggest a positive value for
u u d The presence of a uudss piece in the proton wave function.
pentaquark The proton wave functions with 5q component with
The corresponding spatial state labeled by
spin orbital color singlet color orbital-flavor-spin flavor-spin flavor Construction of multiquark states in group theory.Y. Yan, S. Srisuphaphon Prog.Part.Nucl.Phys. 67 (2012) 496-501
color orbital-flavor-spin orbital 1 3 4 2 1 2 4 3 1 2 3 4
spatial spin flavor
Transition amplitude The transition amplitude for f meson production in proton-antiproton annihilation reactions
( ) Choosing the plane wave basis for the relative motion of the proton and antiproton
spin-color-flavor weight are geometrical constants depending on the radial parameters
The protonium wave function in momentum space for fixed isospin I Including the initial state interaction for the atomic state of the system
The partial decay width for the transition of the state to the two-meson state Branching ratio the partial decay width divided by the total width statistical weight
Reducingthe model dependence Choosing a simplified phenomenological approach that has been applied in studies of two-meson branching ratios in nucleon-antinucleon and radiative protonium annihilation. The initial-state interaction coefficients we use a kinematical phase-space factor of the phenomenological form are related to the probability for a protonium state to have isospin I and spin J
Results The effective strength parameter has to be adjusted to data
Conclusions Branching ratios The model prediction only in the configuration of is agree well with the experimental data.
