相关论文: Flavor-singlet spectrum in multi-flavor QCD

We present the first report of the LatKMI collaboration on the the lattice QCD simulation performed at the KMI computer, "$\varphi$", for the cases of 4 flavors and 8 flavors, the latter being expected to be a candidate for the walking…

The existence of non-trivial IR and UV fixed points in gauge theories as a function of the number of fermion flavors and bare coupling is discussed in the light of recent work. It is pointed out that in fact only a small subset of potential…

We present the ground state energy spectra of two-flavored heavy dibaryons in the spin-singlet channel. In particular, the ground state masses of $\Omega_{llQ}\Omega_{llQ}, \Omega_{QlQ}\Omega_{llQ}$ and $\Omega_{QlQ}\Omega_{QlQ}$ states are…

We evaluate the $\pi N!N$, $\pi\Sigma\Sigma$, $\pi\Lambda\Sigma$, $K\Lambda N$ and $K \Sigma N $ coupling constants and the corresponding monopole masses in lattice QCD with two flavors of dynamical quarks. The parameters representing the…

We show that a new strongly interacting sector can produce large enhancements of the t-tbar asymmetries at the Tevatron. The Standard Model is extended by a new vector-like flavor triplet of fermions and one heavy scalar, all charged under…

One of the most challenging hurdles to the construction of realistic composite Higgs models is the generation of Yukawa couplings for the Standard Model fermions. This problem can be successfully addressed in approximate conformal theories…

The subprocess $gg \to t\bar{c}+\bar{t}c$ in the two-Higgs-doublet model with flavor-changing scalar couplings is examined at the one loop level. With perturbative QCD factorization theorem, the corresponding cross sections for…

Short-distance new physics at (or slightly) above the TeV scale should not excessively violate the approximate flavor symmetries of the SM in order to comply with stringent constraints from flavor-changing neutral currents. In this respect,…

The splittings between the spin 1/2 and spin 3/2 iso-singlet baryons Lambda_s(1405) and Lambda_s(1520), and their charmed counterparts Lambda_c(2593) and Lambda_c(2625), have been a theoretical conundrum. Here we investigate the possibility…

This review considers models with extended Higgs sectors in which there are tree-level flavor-changing neutral currents (FCNC) mediated by scalars. After briefly reviewing models without tree-level FCNC, several models with such currents…

In this paper, we discuss the multi-Higgs doublet models, that could be effectively induced by the extended Standard Model (SM). In particular, we focus on the phenomenology in the supersymmetric model with left-right (LR) symmetry, where…

We study a minimal modification of Gauge Mediation in which the messenger sector couples directly to the MSSM matter fields. These couplings are controlled by the same dynamics that explain the flavor hierarchies, and therefore are…

We measure glueball masses and the string tension in twelve-flavour QCD, aiming at comparing the emerging gluonic spectrum to the mesonic one. When approaching the critical surface at zero quark mass, the hierarchy of masses in the…

Baker, Ball and Zachariasen have developed an elegant formulation of the dual superconducting model of quantum chromodynamics (QCD), which allows one to use the field equations to eliminate the gluon and Higgs degrees of freedom and thus to…

SU(3) gauge theory with eight massless flavours is believed to be walking, while the corresponding twelve- and four-flavour appear IR-conformal and confining respectively. Looking at the simulations performed by the LatKMI collaboration of…

We present the report of the LatKMI collaboration on the lattice QCD simulation for the cases of 4 and 8 flavors. The Nf=8 in particular is interesting from the model-building point of view: The typical walking technicolor model with the…

Using the Sigma model to explore the lowest order pseudo-scalar spectrum with SU(3) breaking, this talk considers an additional exact "taste" symmetry to mimic species doubling. Rooting replicas of a valid approach such as Wilson fermions…

In the search for a realistic walking technicolor model, QCD with many flavors is an attractive candidate. From the series of studies by the LatKMI collaboration, we present updated results of the scaling properties of various hadron…

We present a new lattice study of the discrete beta function for SU(3) gauge theory with Nf=8 massless flavors of fermions in the fundamental representation. Using the gradient flow running coupling, and comparing two different nHYP-smeared…

We discuss the conditions under which the flavor structure of SUSY model induces, either radiatively or through mixing, new flavor-violating interactions in the Higgs sector. The radiative flavor mediation mechanism is illustrated using the…