Quark mass dependence of pseudo-scalar masses and coupling constants

The dependence of pseudo-scalar masses and decay constants on the sea and valence quark masses is investigated in the pseudo-Goldstone boson sector of QCD with two light quark flavours. The sea quark masses are at present in the range 1/3m_s #<=# m_u_d #<=# 2/3 m_s whereas the valence quark masses satisfy 1/2m_s_e_a #<=# m_v_a_l #<=# 2m_s_e_a. The values of the Gasser-Leutwyler low energy constants L_4, L_5, L_6 and L_8 are estimated. The computation is done with the Wilson-quark lattice action at gauge coupling #beta#=5.1 on 16"4 lattices. O(a) effects are taken into account by applying chiral perturbation theory for the Wilson lattice action as proposed by Rupak and Shoresh. (orig.)Available from TIB Hannover: RA 2999(03-148) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman