We investigate Wilson twisted mass fermions in the quenched approximation using different definitions of the critical bare quark mass m(c) to realize maximal twist and, correspondingly, automatic O(a) improvement for physical observables. A particular definition of m(c) is given by extrapolating the value of m(c) obtained from the PCAC relation at non-vanishing bare twisted quark mass mu to mu = 0. Employing this improved definition of the critical mass the Wilson twisted mass formulation provides the possibility to perform reliable simulations down to very small quark masses with correspondingly small pion masses of m(pi) similar or equal to 250 MeV, while keeping the cutoff effects of O(a(2)) under control. (c) 2005 Elsevier B.V. All rights reserved.
Light quarks with twisted mass fermions / K., Jansen; Papinutto, MAURO LUCIO; A., Shindler; C., Urbach; I., Wetzorke. - In: PHYSICS LETTERS. SECTION B. - ISSN 0370-2693. - 619:1-2(2005), pp. 184-191. [10.1016/j.physletb.2005.05.051]
Light quarks with twisted mass fermions
PAPINUTTO, MAURO LUCIO;
2005
Abstract
We investigate Wilson twisted mass fermions in the quenched approximation using different definitions of the critical bare quark mass m(c) to realize maximal twist and, correspondingly, automatic O(a) improvement for physical observables. A particular definition of m(c) is given by extrapolating the value of m(c) obtained from the PCAC relation at non-vanishing bare twisted quark mass mu to mu = 0. Employing this improved definition of the critical mass the Wilson twisted mass formulation provides the possibility to perform reliable simulations down to very small quark masses with correspondingly small pion masses of m(pi) similar or equal to 250 MeV, while keeping the cutoff effects of O(a(2)) under control. (c) 2005 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
