TY  - JOUR
AU  - Carrasco, N.
AU  - Ciuchini, M.
AU  - Dimopoulos, P.
AU  - Frezzotti, R.
AU  - Gimenez, V.
AU  - Herdoiza, G.
AU  - Lubicz, V.
AU  - Michael, C.
AU  - Picca, E.
AU  - Rossi, G. C.
AU  - Sanfilippo, F.
AU  - Shindler, A.
AU  - Silvestrini, L.
AU  - Simula, S.
AU  - Tarantino, C.
PY  - 2014
DA  - 2014//
TI  - B-physics from N-f=2 tmQCD: the Standard Model and beyond
T2  - J. High Energy Phys.
JO  - Journal of High Energy Physics
SP  - 016
EP  - 52pp
VL  - 03
IS  - 3
PB  - Springer
KW  - Lattice QCD
KW  - B-Physics
KW  - Beyond Standard Model
KW  - Quark Masses and SM Parameters
AB  - We present a lattice QCD computation of the b-quark mass, the B and B-s decay constants, the B-mixing bag parameters for the full four-fermion operator basis as well as determinations for xi and f(Bq) root B-i((q)) extrapolated to the continuum limit and to the physical pion mass. We used N-f = 2 twisted mass Wilson fermions at four values of the lattice spacing with pion masses ranging from 280 to 500 MeV. Extrapolation in the heavy quark mass from the charm to the bottom quark region has been carried out on ratios of physical quantities computed at nearby quark masses, exploiting the fact that they have an exactly known infinite mass limit. Our results are m(b)(m(b), (MS) over bar) = 4.29(12) GeV, f(Bs) = 228(8) MeV, f(B) = 189(8) MeV and f(Bs)/f(B) = 1.206(24). Moreover with our results for the bag-parameters we find xi = 1.225(31), B-1((s))/B-1((d)) = 1.01(2), f (Bd) root(B) over cap ((d))(1) = 216(10) MeV and integral Bs root(B) over cap ((s))(1) = 262(10) MeV. We also computed the bag parameters for the complete basis of the four-fermion operators which are required in beyond the SM theories. By using these results for the bag parameters we are able to provide a refined Unitarity Triangle analysis in the presence of New Physics, improving the bounds coming from B-(s) -(B) over bar ((s)) mixing.
SN  - 1029-8479
UR  - http://arxiv.org/abs/1308.1851
UR  - https://doi.org/10.1007/JHEP03(2014)016
DO  - 10.1007/JHEP03(2014)016
LA  - English
N1  - WOS:000347824200001
ID  - Carrasco_etal2014
ER  -