TY  - JOUR
AU  - Constantinou, M.
AU  - Dimopoulos, P.
AU  - Frezzotti, R.
AU  - Jansen, K.
AU  - Gimenez, V.
AU  - Lubicz, V.
AU  - Mescia, F.
AU  - Panagopoulos, H.
AU  - Papinutto, M.
AU  - Rossi, G. C.
AU  - Simula, S.
AU  - Skouroupathis, A.
AU  - Stylianou, F.
AU  - Vladikas, A.
PY  - 2011
DA  - 2011//
TI  - B-K-parameter from N-f=2 twisted mass lattice QCD
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 014505
EP  - 20pp
VL  - 83
IS  - 1
PB  - Amer Physical Soc
AB  - We present an unquenched N-f = 2 lattice computation of the B-K parameter which controls K-0 – (K) over bar (0) oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B-K parameter which is both multiplicatively renormalizable and O(a) improved. Employing the nonperturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B-K(RGI) = 0.729 +/- 0.030, a number well in line with the existing quenched and unquenched determinations.
SN  - 1550-7998
UR  - http://arxiv.org/abs/arXiv:1009.5606
UR  - https://doi.org/10.1103/PhysRevD.83.014505
DO  - 10.1103/PhysRevD.83.014505
LA  - English
N1  - ISI:000286761700002
ID  - Constantinou_etal2011
ER  -