English

Resonance enhancement of Charm CP

High Energy Physics - Phenomenology 2019-05-14 v2 High Energy Physics - Experiment High Energy Physics - Lattice

Abstract

It is suggested that a nearby 0++0^{++} resonance, f0f_0(1710) of mass mf=1723MeVm_f=1723 MeV and width Γ=139\Gamma=139 MeV is playing a significant role in efficiently providing the strong (CP-conserving) and weak (CP-odd) phase simultaneously in the recently observed direct CP asymmetry ΔACP\Delta A_{CP} by the LHCb collaboration. The direct CP arises by the well known penguin-tree interference wherein the virtual b-quark in the c-u penguin is the source of the Kobayashi-Maskawa CP-odd phase, γ\gamma, in the SM. Loop (penguin) corrections generate left-right operators enhancing coupling to the 0++0^{++} scalar resonance. The scalar resonance is likely rich in gluonic content perhaps leading to a better understanding of large breaking of flavor SU(3) that has been known for a long-time. Approximate calculations give a rough understanding of the observed size of the CP asymmetry. The mechanism leads to several interesting implications which can be experimentally studied and tested. Moreover, in an analogous fashion to f0f_0, 4-quark operators also generate P×PP \times P, P being a pseudo-scalar bilinear, which may be dominated by the nearby η(1760)\eta (1760) of width about 250 MeV that can influence final states such as 4 π\pi's, η(η)+π++π\eta^{\prime}(\eta) + \pi^+ + \pi^- etc which could exhibit CP violating triple correlation or energy asymmetries. We also briefly discuss CP violation in radiative charm decays and suggest that simple final states γρ\gamma \rho and γϕ\gamma \phi are best suited for sizeable asymmetries as well as providing precise tests of the SM.

Keywords

Cite

@article{arxiv.1905.00907,
  title  = {Resonance enhancement of Charm CP},
  author = {Amarjit Soni},
  journal= {arXiv preprint arXiv:1905.00907},
  year   = {2019}
}

Comments

9 pages, 2 figures