Related papers: Diphotons, New Vacuum Angles, and Strong CP
Photodisintegration of the deuteron above $\pi$ threshold is studied in a coupled channel approach including $N \Delta$ and $\pi d$ channels with consideration of pion retardation in potentials and exchange currents. A much improved…
Motivated by the $2.8\sigma$ discrepancy observed between the BaBar measurement and the Standard Model prediction of the CP asymmetry in $\tau\to K_S\pi\nu_\tau$ decays, as well as the prospects of future measurements at Belle II, we…
K -> Pi Pi decays are investigated in the framework of the SU(2)left x U(1) gauge theory of J=0 mesons proposed in ref.[1], to which is added an interaction between mesons respecting the two symmetries generally attributed to strong…
We propose to interpret the 750 GeV diphoton excess in deflected anomaly mediation supersymmetry breaking scenarios, which can naturally predict couplings between a singlet field and vector-like messengers. The CP-even scalar component (S)…
The recently measured direct CP asymmetries in the processes $D^0\to \pi^+\pi^-$ and $D^0\to K^+K^-$ show a significant deviation from the naive Standard Model expectation. Using a general parameterization of the decay amplitudes, we show…
Effective field theory arguments suggest that if BSM sectors contain new sources of CP-violation that couple to QCD, these sources will renormalize the $\theta$ term and frustrate ultraviolet solutions to the strong CP problem.…
The photoproduction of pion off nucleon is investigated within a dynamical coupled-channels approach based on the Juelich pi-N model, which has been quite successful in the description of pi-N to pi-N scattering for center-of-mass energies…
The Higgs sector in neutral naturalness models provides a portal to the hidden sectors, and thus measurements of Higgs couplings at current and future colliders play a central role in constraining the parameter space of the model. We…
The parity-violating (PV) asymmetry of inclusive $\pi^-$ production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360…
We interpret the 750~GeV diphoton excess recently found in the 13~TeV LHC data as a singlet scalar in an extra dimensional model, where one extra dimension is introduced. In the model, the scalar couples to multiple vector-like fermions,…
The absence of a neutron electric dipole moment (EDM) constrains the quantum chromodynamics (QCD) theta angle to be less than one part in ten billion, posing the Strong $CP$ problem. We revisit two classes of proposed solutions. First, we…
If New Physics contributes significantly to neutral meson mixing, then it is quite likely that it does so in a CP violating manner. In $D^0-\bar D^0$ mixing measured through $D^0\rightarrow K^+\pi^-$, CP violation induces a term $\propto…
A new possibility for solving the strong CP-problem is suggested,which assumes that apart of the ordinary world of observable particles described by standard model, there exits a mirror sector of particles and two sectors share the same…
We present a relativistic dynamical model of pion photoproduction on the nucleon in the resonance region. It offers several advances over the existing approaches. The model is obtained by extending our $\pi N$-scattering description to the…
We study the neutral pion photoproduction at near-threshold energies in fully covariant chiral perturbation theory up to O(p^3). When including only nucleonic virtual states in the model, the convergence is too slow. Therefore we test the…
New data are presented on the p(e,e'p)\pi^0 reaction at threshold at a four-momentum transfer of Q^2=0.05 GeV^2/c^2. The data were taken with the three-spectrometer setup of the A1 Collaboration at the Mainz Microtron MAMI. The complete…
Motivated by the recent LHC discovery of the di-photon excess at the invariant mass of ~ 750 GeV, we study the prospect of investigating the scalar resonance at a future photon-photon collider. We show that, if the di-photon excess observed…
Within the standard model, non-renormalizable operators at dimension six ($d=6$) violate baryon and lepton number by one unit and thus lead to proton decay. Here, we point out that the proton decay mode with a charged pion and missing…
The invariant mass spectra of the $pp\pi^-$ and $pp$ systems produced in the double charge exchange (DCX) of positively charged pions on photoemulsion are analysed. A pronounced peak is observed in the $pp\pi^-$ invariant mass spectrum,…
We revisit a set of dark sector models, motivated by anomalies observed in $B$ decays and the muon anomalous magnetic moment, in the light of a recently reported diphoton excess around 750$\,$GeV. Interpreting the excess as a scalar…