Related papers: Comment on "The QCD axion beyond the classical lev…
It follows on general grounds that the theta dependence in QCD is more complicated than suggested by the large N_c approach or instanton arguments. Generically, the vacuum energy E_{vac}(\theta) is a multi-valued function of \theta…
The quantum chromodynamics (QCD) axion arises as the pseudo-Goldstone mode of a spontaneously broken abelian Peccei-Quinn (PQ) symmetry. If the scale of PQ symmetry breaking occurs below the inflationary reheat temperature and the domain…
We study single-particle potential of hyperons in nuclear medium starting from QCD. First we carry out lattice QCD numerical simulation to extract baryon-baryon interactions from QCD by means of the HAL QCD method. We employ a full QCD…
Considerable theoretical efforts have gone into expanding the reach of the QCD axion beyond its canonical mass--decay-constant relation. The $Z_\mathcal{N}$ QCD axion model reduces the QCD axion mass naturally, by invoking a discrete…
The axion is a hypothetical low-mass boson predicted by the Peccei-Quinn mechanism solving the strong CP problem. It is naturally also a cold dark matter candidate if its mass is below $\sim$\,1\,meV, thus simultaneously solving two major…
We calculate the pion and rho meson masses in quenched SU(N) gauge theories for N = 2, 3, 4 and 6. Extrapolating these results to the chiral and large-N limits, we find m_rho = (1.670 +/- 0.024) sqrt(sigma) = (741 +/- 11) MeV for the rho…
We discuss the bound on the mass of the Higgs boson arising from precision electroweak measurements in the context of the triviality of the scalar Higgs model. We show that, including possible effects from the underlying nontrivial…
Older lattice work exploring the Higgs mass triviality bound is briefly reviewed. It indicates that a strongly interacting scalar sector in the minimal standard model cannot exist; on the other hand low energy QCD phenomenology might be…
We determine the mass and decay constant of the $a_1$ meson using Monte Carlo simulation of lattice QCD. We find $M_{a_1} = 1250 \pm 80$ MeV and $f_{a_1} = 0.30 \pm 0.03 ~({\rm GeV})^2$, in good agreement with experiment.
We evaluate the infinite volume, continuum limits of eight hadron mass ratios predicted by lattice QCD with Wilson quarks in the valence (quenched) approximation. Each predicted ratio differs from the corresponding observed value by less…
After a quick review of astrophysically relevant limits, I present a summary of MeV scale tau neutrino mass limits derived from accelerator based experiments. I argue that the current published limits appear to be too consistent, and that…
We describe an efficient algorithm to compute a large number of baryon-baryon interactions from $NN$ to $\Xi\Xi$ by means of HAL QCD method, which lays the groundwork for the nearly physical point lattice QCD calculation with volume…
The properties of the QCD axion are strictly related to the dependence of strong interactions on the topological parameter theta. We present a determination of the topological properties of QCD for temperatures up to around 600 MeV,…
We evaluate the infinite volume, continuum limit of glueball masses in the valence (quenched) approximation to lattice QCD. For the lightest scalar and tensor states we obtain masses of $1648 \pm 58$ MeV and $2267 \pm 104$ MeV,…
In this work, we investigate the effective parameter space associated with the axion mass and the axion decay constant in both the light and heavy QCD axion scenarios. We initiate our discussion by considering the simplest case of two…
The QCD axion offers a natural resolution to the strong CP problem and provides a compelling dark matter candidate. If the QCD axion constitutes all the dark matter, the simplest models pick out a narrow range of masses around $100\,\mu{\rm…
We improve the precision of the topological susceptibility of QCD, and therefore of the QCD axion mass, by including $O(\alpha_{\rm em})$ and NNLO corrections in the chiral expansion, which amount to 0.65(21)% and -0.71(29)% respectively.…
We re-analyse meson sector data from the CP-PACS collaboration's dynamical simulations. Our analysis uses several different approaches, and compares the standard naive linear fit with the Adelaide Anzatz. We find that setting the scale…
We present the results of an extended scaling test of quenched Wilson twisted mass QCD. We fix the twist angle by using two definitions of the critical mass, the first obtained by requiring the vanishing of the pseudoscalar meson mass m_PS…
The QCD axion has been postulated to exist because it solves the strong CP problem. Furthermore, if it exists axions should be created in the early Universe and could account for all the observed dark matter. In particular, axion masses of…