0000000000755255

AUTHOR

A. Amghar

showing 3 related works from this author

Point-Form estimate of the pion form factor revisited

2003

The pion form factor calculation in the ``point-form'' of relativistic quantum mechanics is re-considered. Particular attention is given to the relation between the momentum of the system and the momentum transfer as well as to the quark current.

Nuclear Theory (nucl-th)[PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph]High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Nuclear Theory[PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th]High Energy Physics::Lattice[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]Nuclear TheoryFOS: Physical sciences[PHYS.HTHE] Physics [physics]/High Energy Physics - Theory [hep-th]
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The form factor of the pion in point-form of relativistic dynamics revisited

2003

The electromagnetic form factor of the pion is calculated in the "point-form" of relativistic quantum mechanics using simple, phenomenological wave functions. It is found that the squared charge radius of the pion is predicted one order of magnitude larger than the experimental value and the asymptotic behavior expected from QCD cannot be reproduced. The origin of these discrepancies is analyzed. The present results confirm previous ones obtained from a theoretical model and call for major improvements in the implementation of the "point-form" approach.

Quantum chromodynamicsPhysicsNuclear and High Energy Physics[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]010308 nuclear & particles physicsPoint-form relativistic dynamicsForm factor (quantum field theory)Relativistic dynamicsFOS: Physical sciencesRelativistic quantum mechanics01 natural sciencesPion form factorHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)PionCharge radiusQuantum electrodynamics0103 physical sciences010306 general physicsWave functionOrder of magnitude
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Comparison of different boost transformations for the calculation of form factors in relativistic quantum mechanics

2002

The effect of different boost expressions, pertinent to the instant, front and point forms of relativistic quantum mechanics, is considered for the calculation of the ground-state form factor of a two-body system in simple scalar models. Results with a Galilean boost as well as an explicitly covariant calculation based on the Bethe-Salpeter approach are given for comparison. It is found that the present so-called point-form calculations of form factors strongly deviate from all the other ones. This suggests that the formalism which underlies them requires further elaboration. A proposition in this sense is made.

PhysicsParticle physics010308 nuclear & particles physics[PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th]FOS: Physical sciencesRelativistic quantum mechanics01 natural sciencesGalileanHigh Energy Physics - PhenomenologyFormalism (philosophy of mathematics)Classical mechanicsHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesRelativistic mechanicsCovariant transformation[PHYS.HTHE] Physics [physics]/High Energy Physics - Theory [hep-th]010306 general physics
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