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We investigate the processes $e^+e^-$$to$$gamma J/psiphi$, $gamma J/psiomega$ and $pi^0 J/psieta$ to search for the charmnium-like states with hidden $sbar{s}$, such as $Y(4140)$, $Y(4274)$, $X(4350)$ and $X(3915)$. These processes will receive contributions from the charmed-strange meson rescatterings. When the center-of-mass energies of the $e^+e^-$ scatterings are taken around the $D_{s0}(2317)D_s^{*}$, $D_{s1}(2460)D_s$ or $D_{s1}(2460)D_s^{*}$ threshold, the anomalous triangle singularities can be present in the rescattering amplitudes, which implies a non-resonance explanation about the resonance-like structures. The positions of the anomalous triangle singularities are sensitive to the kinematics, which offers us a criterion to distinguish the kinematic singularities from genuine particles.
The possibility of the $0^+$ $etaeta$ resonance $f_0(2100)$ as a candidate of the $Q^2bar{Q}^2$ state $C^{ss}(36)$ is explored. The $etaeta$ channel of $f_0(2100)$ is the dominant decay mode, $etaeta$ channel has less decay rate, the decay rate of the $etaeta$ channel is very small. The $pipi,;Kbar{K},;4pi$ modes are at next leading order in $N_C$ expansion. Other possible decay modes are discussed.
We reemphasize that the ratio $R_{smu} equiv overline{mathcal{B}}(B_stomubarmu)/Delta M_s$ is a measure of the tension of the Standard Model (SM) with latest measurements of $overline{mathcal{B}}(B_stomubarmu)$ that does not suffer from the persistent puzzle on the $|V_{cb}|$ determinations from inclusive versus exclusive $bto cellbar u$ decays and which affects the value of the CKM element $|V_{ts}|$ that is crucial for the SM predictions of both $overline{mathcal{B}}(B_stomubarmu)$ and $Delta M_s$, but cancels out in the ratio $R_{smu}$. In our analysis we include higher order electroweak and QED corrections und adapt the latest hadronic input to find a tension of about $2sigma$ for $R_{smu}$ measurements with the SM independently of $|V_{ts}|$. We also discuss the ratio $R_{dmu}$ which could turn out, in particular in correlation with $R_{smu}$, to be useful for the search for New Physics, when the data on both ratios improves. Also $R_{dmu}$ is independent of $|V_{cb}|$ or more precisely $|V_{td}|$.
Just as Quantum Electrodynamics describes how electrons are bound in atoms by the electromagnetic force, mediated by exchange of photons, Quantum Chromodynamics (QCD) describes how quarks are bound inside hadrons by the strong force, mediated by exchange of gluons. At face value, QCD allows hadrons constructed from increasingly many quarks to exist, just as atoms with increasing numbers of electrons exist, yet such complex constructions seemed, until recently, to not be present in nature. In what follows we describe advances in the spectroscopy of mesons that are refining our understanding of the rules for building hadrons from QCD.
We investigate the anomalous triangle singularity (ATS) and its possible manifestations in various processes. We show that the ATS should have important impact on our understanding of the nature of some newly observed threshold states. Discussions on how to distinguish the ATS phenomena from genuine dynamic pole structures are presented.
We examine the prospects of probing nonstandard interactions (NSI) of neutrinos in the e-tau sector with upcoming long-baseline nu_mu -> nu_e oscillation experiments. First conjectured decades ago, neutrino NSI remain of great interest, especially in light of the recent 8B solar neutrino measurements by SNO, Super-Kamiokande, and Borexino. We observe that the recent discovery of large theta_13 implies that long-baseline experiments have considerable NSI sensitivity, thanks to the interference of the standard and new physics conversion amplitudes. In particular, in some parts of NSI parameter space, the upcoming NOvA experiment will be sensitive enough to see ~ 3sigma deviations from the SM-only hypothesis. On the flip side, NSI introduce important ambiguities in interpreting NOvA results as measurements of CP-violation, the mass hierarchy and the octant of theta_23. In particular, observed CP violation could be due to a phase coming from NSI, rather than the vacuum Hamiltonian. The proposed LBNE experiment, with its longer ~ 1300 km baseline, may break many of these interpretative degeneracies.