Amarjit Soni

Learn More
We report the first lattice QCD calculation of the complex kaon decay amplitude A_{0} with physical kinematics, using a 32³×64 lattice volume and a single lattice spacing a, with 1/a=1.3784(68) GeV. We find Re(A_{0})=4.66(1.00)(1.26)×10(-7) GeV and Im(A_{0})=-1.90(1.23)(1.08)×10(-11) GeV, where the first error is statistical and the second systematic. The(More)
We show that it is possible to construct ǫ/ǫ to NLO using partially quenched chiral perturbation theory (PQChPT) from amplitudes that are computable on the lattice. We demonstrate that none of the needed amplitudes require three-momentum on the lattice for either the full theory or the partially quenched theory; non-degenerate quark masses suffice.(More)
We present the first results for neutral-kaon mixing using (2+1)-flavors of domain-wall fermions. A new approach is used to extrapolate to the physical up and down quark masses from our numerical studies with pion masses in the range 240-420 MeV; only SU(2)_{L}xSU(2)_{R} chiral symmetry is assumed and the kaon is not assumed to be light. Our main result is(More)
In the Standard Model (SM) the photon in radiative B̄ and B̄s decays is predominantly left-handed. Thus, mixing induced CP asymmetries in b→ sγ and b → dγ are suppressed by ms/mb and md/mb, respectively, and are very small. In many extensions of the SM, such as the left-right symmetric model (LRSM), SU(2) × U(1) models with exotic fermions and SUSY, the(More)
We present the first results for the K13 form factor from simulations with 2+1 flavors of dynamical domain wall quarks. Combining our result, namely, f+(0)=0.964(5) with the latest experimental results for Kl3 decays leads to |V us|=0.2249(14), reducing the uncertaintity in this important parameter. For the O(p6) term in the chiral expansion we obtain Delta(More)
A comprehensive phenomenological analysis of a two Higgs doublet model, with flavor-changing scalar currents at the tree-level, called model III, is presented. Constraints from existing experimental information especially on ∆F = 2 processes are systematically incorporated. Constraints emerging from rare B-decays, Z → bb̄, and the ρ-parameter are also(More)
We present a study of the neutron electric dipole moment (~ dN) within the framework of lattice QCD with two flavors of light quarks. The dipole moment is sensitive to the topological structure of the gauge fields, so accuracy can only be achieved by using dynamical, or sea quark, calculations. The topological charge (distribution) evolves slowly in these(More)
We consider several hints for new physics involving CP-asymmetries in B-decays and interpret them in terms of generic contributions to effective Wilson coefficients. The effects we focus on are: the differences in the fitted value of sin 2β versus the ones directly measured via the time dependent CP asymmetries in B → J/ψK or via B → (φ, η)K; the difference(More)