0000000001186423
AUTHOR
S. Simula
Extraction of HQE parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses
We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to $\simeq 4$ times the physical b-quark mass. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with $N_f = 2+1+1$ dynamical quarks at three values of the lattice spacing ($a \simeq 0.062, 0.082, 0.089$ fm) with pion masses in the range $M_\pi \simeq 210 - 450$ MeV. The heavy-quark mass is simulated directly on the lattice up to $\simeq 3$ times the physical charm mass. The interpolation to the physical $b$-quark mass is performed using the ETMC ratio method, based on ratios of the meson mass…
Dynamical twisted mass fermions with light quarks: simulation and analysis details
In a recent paper [hep-lat/0701012] we presented precise lattice QCD results of our European Twisted Mass Collaboration (ETMC). They were obtained by employing two mass-degenerate flavours of twisted mass fermions at maximal twist. In the present paper we give details on our simulations and the computation of physical observables. In particular, we discuss the problem of tuning to maximal twist, the techniques we have used to compute correlators and error estimates. In addition, we provide more information on the algorithm used, the autocorrelation times and scale determination, the evaluation of disconnected contributions and the description of our data by means of chiral perturbation theo…
Non-perturbatively renormalised light quark masses from a lattice simulation with N(f) = 2
We present results for the light quark masses obtained from a lattice QCD simulation with N-f = 2 degenerate Wilson dynamical quark flavours. The sea quark masses of our lattice, of spacing a similar or equal to 0.06 fm, are relatively heavy, i.e., they cover the range corresponding to 0.60 less than or similar to M-p/M-V less than or similar to 0.75. After implementing the non-perturbative RI-MOM method to renormalise quark masses, we obtain m(ud)((MS) over bar)(2 GeV)= 4.3 +/- 0.4(-0)(+1.1) MeV, and m(s)((MS) over bar)(2 GeV) = 101 +/- 8(-0)(+25) MeV, which are about 15% larger than they would be if renormalised perturbatively. In addition, we show that the above results are compatible wi…
Dynamical twisted mass fermions with light quarks
We present results of dynamical simulations with 2 flavours of degenerate Wilson twisted mass quarks at maximal twist in the range of pseudo scalar masses from 300 to 550 MeV. The simulations are performed at one value of the lattice spacing a \lesssim 0.1 fm. In order to have O(a) improvement and aiming at small residual cutoff effects, the theory is tuned to maximal twist by requiring the vanishing of the untwisted quark mass. Precise results for the pseudo scalar decay constant and the pseudo scalar mass are confronted with chiral perturbation theory predictions and the low energy constants F, \bar{l}_3 and \bar{l}_4 are evaluated with small statistical errors.
D-0 - (D)over-bar(0) mixing in the standard model and beyond from N-f=2 twisted mass QCD
We present the first unquenched lattice QCD results for the bag parameters controlling the short distance contribution to D meson oscillations in the standard model and beyond. We have used the gauge configurations produced by the European Twisted Mass collaboration with N-f = 2 dynamical quarks, at four lattice spacings and light meson masses in the range 280-500 MeV. Renormalization is carried out nonperturbatively with the regularization-independent momentum subtraction method. The bag-parameter results have been used to constrain new physics effects in D-0 ¿ (D) over bar (0) mixing, to put a lower bound to the generic new physics scale and to constrain off-diagonal squark mass terms for…
Up, down, strange and charm quark masses with N-f=2+1+1 twisted mass lattice QCD
We present a lattice QCD calculation of the up, down, strange and charm quark masses performed using the gauge configurations produced by the European Twisted Mass Collaboration with N-f = 2 + 1 + 1 dynamical quarks, which include in the sea, besides two light mass degenerate quarks, also the strange and charm quarks with masses close to their physical values. The simulations are based on a unitary setup for the two light quarks and on a mixed action approach for the strange and charm quarks. The analysis uses data at three values of the lattice spacing and pion masses in the range 210-450 MeV, allowing for accurate continuum limit and controlled chiral extrapolation. The quark mass renorma…