Related papers: Singlet Mesons in Dark $Sp(4)$ Theories
We investigate the vector, axial and pseudo scalar mass spectrum of an SO(4) - MWT gauge theory with fermions in the vector representation of SO(4). Here we present the preliminary lattice results for the masses of vector and axial vector…
The Lattice Strong Dynamics collaboration is investigating the properties of a SU(3) gauge theory with $N_f = 8$ light fermions on the lattice. We measure the masses of the lightest pseudoscalar, scalar and vector states using simulations…
We try to interpret a very light dark matter with mass of 5~10 GeV which is in favor of the recent experiments reported by CoGeNT and DAMA, in a non-supersymmetric extension of radiative seesaw model with a family symmetry D_6 x Z_2 x Z_2.…
We take the MSSM as a complete theory of low energy phenomena, including neutrino masses and mixings. This immediately implies that the gravitino is the only possible dark matter candidate. We study the implications of the astrophysical…
A recent model of dark energy and dark matter was proposed, involving a new gauge group $SU(2)_Z$ whose coupling grows strong at a scale $\Lambda_Z \sim 10^{-3} eV$, a result which is obtained from a simple assumption that its initial value…
Gauginos may be nearly massless at tree level, with loop corrections giving a gluino mass of order 100 MeV and a photino mass of order 1 GeV. Relic photinos can naturally account for the observed dark matter, but their detection is more…
We discuss the role of meson exchange mechanisms in $\gamma \gamma \to \gamma \gamma$ scattering. Several pseudoscalar ($\pi^0$, $\eta$, $\eta'(958)$, $\eta_c(1S)$, $\eta_c(2S)$), scalar ($f_{0}(500)$, $f_0(980)$, $a_0(980)$, $f_0(1370)$,…
The behavior of neutral pseudoscalar mesons $\pi^0, \eta$ and $\eta'$ in hot and dense matter is investigated, in the framework of the three flavor Nambu-Jona-Lasinio model. Three different scenarios are considered: zero density and finite…
We present our model-independent and data-driven method to describe pseudoscalar meson transition form factors in the space- and (low-energy) time-like regions. The method is general and conforms a toolkit applicable to any other form…
Meson spin splittings are examined within an effective Coulomb gauge QCD Hamiltonian incorporating chiral symmetry and a transverse hyperfine interaction necessary for heavy quarks. For light and heavy quarkonium systems the…
Several SU(N) gauge theories have been explored as candidates for producing stable dark matter particles that can explain their relative abundance, while also evading current constraints from direct, indirect and collider searches. In this…
We investigate the possibility that Dark Matter arises as a composite state of a fundamental confining dynamics, together with the Higgs boson. We focus on the minimal SU(4)$\times$SU(4)/SU(4) model which has both a Dark Matter and a Higgs…
Combining the recent lattice calculation of $a_0(1450)$ and $\sigma(600)$ mesons with the overlap fermion in the chiral regime with the pion mass less than $300 {\rm MeV}$, the quenched lattice calculation of the scalar glueball, and the…
I present a simple discussion of the masses and mixings of the light pseudoscalar and vector mesons based on a ``$q\bar{q}$'' description of the effective field theory. The analysis includes $\eta'$(958) from the beginning, and is largely…
We report the findings of our extensive study of the spectra of flavoured mesons in lattice gauge theories with symplectic gauge group and fermion matter content treated in the quenched approximation. For the $Sp(4)$, $Sp(6)$, and $Sp(8)$…
SU(2) gauge theory with a single fermion in the fundamental representation is a minimal non-Abelian candidate for the dark matter sector, which is presently missing from the standard model. Having only a single flavor provides a natural…
Cosmic ray anomalies observed by PAMELA and Fermi-LAT experiments may be interpreted by heavy (TeV-scale) dark matter annihilation enhanced by Sommerfeld effects mediated by a very light (sub-GeV) U(1)_X gauge boson, while the recent direct…
Spectral densities encode non-perturbative information crucial in computing physical observables in strongly coupled field theories. Using lattice gauge theory data, we perform a systematic study to demonstrate the potential of recent…
We establish a hybrid seesaw mechanism to explain small neutrino masses and predict cold dark matter candidate in the context of the B-L gauge symmetry extension of the Standard Model. In this model a new scalar doublet and two new fermion…
The pseudoscalar and vector heavy meson masses are calculated in the \epsilon-regime of Heavy Meson Chiral Perturbation Theory to order \epsilon^4. The results of this calculation will allow the determination of low-energy coefficients…