0000000000434590
AUTHOR
C.t. Sachrajda
showing 6 related works from this author
Pion form factor from RBC and UKQCD
2010
Andreas Juttner, P.A. Boyle, C. Kelly, C. Maynard, J.M. Zanotti, J.M. Flynn, H.P. de Lima, C.T. Sachrajda
Matrix elements of decays
2004
We present a numerical computation of matrix elements of ?I = 3/2 K ? ?? decays by using Wilson fermions. In order to extrapolate to the physical point we work at unphysical kinematics and we resort to Chiral Perturbation Theory at the next-to-leading order. In particular we explain the case of the electroweak penguins 07,8 which can contribute significantly in the theoretical prediction of sol|??/?. The study is done at ? = 6.0 on a 243 × 64 lattice.
Geometrical volume effects in the computation of the slope of the isgur-wise function
1994
We use a method recently suggested for evaluating the slope of the Isgur-Wise function, at the zero-recoil point, on the lattice. The computations are performed in the quenched approximation to lattice QCD, on a $24^3 \times 48$ lattice at $\beta=6.2$, using an $O(a)$-improved action for the fermions. We have found unexpectedly large finite-volume effects in such a calculation. These volume corrections turned out to be purely geometrical and independent of the dynamics of the system. After the study of these effects on a smaller volume and for different quark masses, we give approximate expressions that account for them. Using these approximations we find $\xi^\prime(1)=-1.7 \pm 0.2$ and $\…
K --> pi pi matrix elements beyond the leading-order chiral expansion
2002
We propose an approach for calculating $K\to\pi\pi$ decays to the next-to-leading order in chiral expansion. A detailed numerical study of this approach is being performed.
Heavy Baryon Specroscopy from the Lattice
1996
The results of an exploratory lattice study of heavy baryon spectroscopy are presented. We have computed the full spectrum of the eight baryons containing a single heavy quark, on a $24^3\times 48$ lattice at $\beta=6.2$, using an $O(a)$-improved fermion action. We discuss the lattice baryon operators and give a method for isolating the contributions of the spin doublets $(\Sigma,\Sigma^*)$, $(\Xi',\Xi^*)$ and $(\Omega,\Omega^*)$ to the correlation function of the relevant operator. We compare our results with the available experimental data and find good agreement in both the charm and the beauty sectors, despite the long extrapolation in the heavy quark mass needed in the latter case. We …
Semi-leptonic Decays of Heavy Flavours on a Fine Grained Lattice
1994
We present the results of a numerical calculation of semi-leptonic form factors relevant for heavy flavour meson decays into light mesons, at $\beta=6.4$ on a $24^3 \times 60$ lattice, using the Wilson action in the quenched approximation. We obtain $f^+_K(0)=0.65\pm 0.18$, $V(0)=0.95\pm 0.34$, $A_1(0)=0.63\pm 0.14 $ and $A_2(0)=0.45\pm 0.33 $. We also obtain $A_1(q^2_{max})=0.62\pm 0.09$, $V(0)/A_1(0)=1.5\pm 0.28 $ and $A_2(0)/A_1(0)=0.7\pm 0.4$. The results for $f^+_K(0)$, $V(0)$ and $A_1(0)$ are consistent with the experimental data and with previous lattice determinations with larger lattice spacings. In the case of $A_2(0)$ the errors are too large to draw any firm conclusion. We have …