Seminar über aktuelle Frage der theoretischen Kernphysik

20.11.12 16:15

Two-pion excited state contribution to the axial-vector and pseudo-scalar correlators

Oliver Baer (HU Berlin)

In lattice computations of hadron masses from two-point functions, excited states have to be taken into account. With pion masses close to the physical value, the nearest excited state may be that of the hadron accompanied by two pions at rest. The amplitude of such excited state contributions can be calculated in chiral perturbation theory. Relative to the ground state, these excited states are suppressed by the square of the spatial volume. This is shown explicitly in the Goldstone meson sector. Somewhat surprisingly, the suppression of the 3-pion state contributions is even stronger than naively expected.

Kategorie: Kernphysik