We discuss the formulation in euclidean space of the effective theory for heavy quarks at non-zero velocity, which is necessary for the implementation of the Isgur-Wise limit in lattice QCD simulations. In this theory the energy spectrum is unbounded from below and, even at the tree level, an ultraviolet cut-off on spatial momenta must be introduced. The continuum limit of the effective quark propagator in configuration space does not exist. It is however possible, at least in the non-interacting case, to construct sensible correlation functions in time and in spatial momenta. The application of the theory to lattice simulations seems very problematic.
PROBLEMS WITH THE EUCLIDEAN FORMULATION OF HEAVY QUARK EFFECTIVE THEORIES / Aglietti, Ugo Giuseppe; M., Crisafulli; M., Masetti. - In: PHYSICS LETTERS. SECTION B. - ISSN 0370-2693. - STAMPA. - 294:2(1992), pp. 281-285. [10.1016/0370-2693(92)90695-z]
PROBLEMS WITH THE EUCLIDEAN FORMULATION OF HEAVY QUARK EFFECTIVE THEORIES
AGLIETTI, Ugo Giuseppe;
1992
Abstract
We discuss the formulation in euclidean space of the effective theory for heavy quarks at non-zero velocity, which is necessary for the implementation of the Isgur-Wise limit in lattice QCD simulations. In this theory the energy spectrum is unbounded from below and, even at the tree level, an ultraviolet cut-off on spatial momenta must be introduced. The continuum limit of the effective quark propagator in configuration space does not exist. It is however possible, at least in the non-interacting case, to construct sensible correlation functions in time and in spatial momenta. The application of the theory to lattice simulations seems very problematic.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
