We present a non-perturbative computation of the running of the coupling alpha_s in QCD with two flavours of dynamical fermions in the Schroedinger functional scheme. We improve our previous results by a reliable continuum extrapolation. The Lambda-parameter characterizing the high-energy running is related to the value of the coupling at low energy in the continuum limit. An estimate of Lambda*r_0 is given using large-volume data with lattice spacings a from 0.07 fm to 0.1 fm. It translates into Lambda_{MSbar}^{(2)}=245(16)(16) MeV [assuming r_0=0.5 fm]. The last step still has to be improved to reduce the uncertainty.
Della Morte, M., Frezzotti, R., Heitger, J., Rolf, J., Sommer, R., Wolff, U. (2005). Computation of the strong coupling in QCD with two dynamical flavors. NUCLEAR PHYSICS. B, 713(1-3), 378-406 [10.1016/j.nuclphysb.2005.02.013].
Computation of the strong coupling in QCD with two dynamical flavors
FREZZOTTI, ROBERTO;
2005-01-01
Abstract
We present a non-perturbative computation of the running of the coupling alpha_s in QCD with two flavours of dynamical fermions in the Schroedinger functional scheme. We improve our previous results by a reliable continuum extrapolation. The Lambda-parameter characterizing the high-energy running is related to the value of the coupling at low energy in the continuum limit. An estimate of Lambda*r_0 is given using large-volume data with lattice spacings a from 0.07 fm to 0.1 fm. It translates into Lambda_{MSbar}^{(2)}=245(16)(16) MeV [assuming r_0=0.5 fm]. The last step still has to be improved to reduce the uncertainty.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.