X iv : h ep - p h / 04 02 16 5 v 1 1 7 Fe b 20 04 Hadron structure in manifestly Lorentz - invariant baryon chiral perturbation theory

ar X iv : h ep - p h / 04 02 29 2 v 1 2 7 Fe b 20 04 1 SU ( 3 ) Chiral Effective Field

A personal overview on the present status of SU(3) chiral perturbation theory in the baryonic sector is given. Recent developments are presented and remaining challenges are pointed out.

ar X iv : h ep - p h / 04 02 23 9 v 1 2 3 Fe b 20 04 The η → π 0 π 0 γγ decay in Generalized χ PT

Calculations of η → ππγγ decay in Generalized chiral perturbation theory are presented. Tree level and next-to-leading corrections are involved. Sensitivity to violation of the Standard counting is discussed.

ar X iv : h ep - p h / 04 02 14 7 v 1 1 3 Fe b 20 04 Contribution of dimension - six bosonic operators to H → γγ at one - loop level

The decay process H → γγ is examined in a model-independent way within the effective Lagrangian approach. Contribution of one-loop diagrams including SU(2) × U(1) invariant dimension-six bosonic operators is evaluated explicitly. The calculation is intended to fill a gap that exists in the current literature of the subject. [email protected] [email protected]

ar X iv : h ep - t h / 04 02 14 8 v 1 1 9 Fe b 20 04 Surveillance on the light - front gauge fixing

In this work we propose two Lagrange multipliers with distinct coefficients for the light-front gauge that leads to the complete (non-reduced) propagator. This is accomplished via (n · A) 2 + (∂ · A) 2 terms in the La-grangian density. These lead to a well-defined and exact though Lorentz non invariant light front propagator.

ar X iv : h ep - p h / 04 02 19 0 v 1 1 8 Fe b 20 04 1 Pentaquarks in the 10 F - and 10 F - plets