Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userLight unflavor vector meson spectroscopy around the mass range of $2.4sim 3$ GeV and possible experimental evidence
127
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
In this work, we predict the spectroscopy behavior of these light unflavor vector mesons with masses at the range of $2.4sim 3$ GeV, which are still missing in experiment. By presenting their mass spectrum and studying their two-body Okubo-Zweig-lizuka allowed decay widths, we discuss the possible experimental evidences of these discussed states combing with the present experimental data. Especially, we strongly suggest our experimental colleague to carry out the exploration of these higher states via the $e^+e^-$ annihilation into light mesons. It is obvious that BESIII and Belle II will be potential experiment to achieve this target.
rate research
Read More
We consider the fidelity of the vector meson dominance (VMD) assumption as an instrument for relating the electromagnetic vector-meson production reaction $e + p to e^prime + V + p$ to the purely hadronic process $V + p to V+p$. Analyses of the photon vacuum polarisation and the photon-quark vertex reveal that such a VMD Ansatz might be reasonable for light vector-mesons. However, when the vector-mesons are described by momentum-dependent bound-state amplitudes, VMD fails for heavy vector-mesons: it cannot be used reliably to estimate either a photon-to-vector-meson transition strength or the momentum dependence of those integrands that would arise in calculations of the different reaction amplitudes. Consequently, for processes involving heavy mesons, the veracity of both cross-section estimates and conclusions based on the VMD assumption should be reviewed, e.g., those relating to hidden-charm pentaquark production and the origin of the proton mass.
In recent years, hints for multi-lepton anomalies have been accumulated by the analysis of Large Hadron Collider (LHC) data, pointing towards the existence of beyond the Standard Model (SM) Higgs bosons: a new scalar particle $S$ with a mass $m_S$ in the range between $130,$GeV and $160,$GeV, produced from the decay of a heavier new scalar particle, $H$. Motivated by this observation, we perform a search for the signatures of $S$ within this mass region, which has been studied by CMS and ATLAS as a by-product of the SM Higgs searches in the side-bands of the kinematic regions. Combining the $gammagamma$ and $Zgamma$ channels, with associated leptons, di-jets, bottom quarks and missing energy, we obtain a local (global) significance of 5.1$sigma$ (4.8$sigma$) for a mass of $m_S= 151.5$,GeV and provide the preferred ranges for the corresponding (fiducial) cross sections. This is a strong indication for a scalar resonance $S$ decaying into photons, and, to a lesser extent to $Zgamma$, in association with missing energy, jets or leptons. Hints for the decays into, or production in association with, bottom quarks are statistically less significant. In order to test this hypothesis, we propose a search for $Hrightarrow gammagamma boverline{b},tau^+tau^- boverline{b}$ in asymmetric configurations that has not yet been performed by ATLAS and CMS.
We extend earlier investigations of heavy-light pseudoscalar mesons to the vector case, using a simple model in the context of the Dyson-Schwinger-Bethe-Salpeter approach. We investigate the effects of a dressed-quark-gluon vertex in a systematic fashion and illustrate and attempt to quantify corrections beyond the phenomenologically very useful and successful rainbow-ladder truncation. In particular we investigate dressed quark photon vertex in such a setup and make a prediction for the experimentally as yet unknown mass of the B_c*, which we obtain at 6.334 GeV well in line with predictions from other approaches. Furthermore, we combine a comprehensive set of results from the theory literature. The theory average for the mass of the B_c* meson is 6.336 +- 0.002 GeV.
In this work we construct 36 tetraquark configurations for the $1S$-, $1P$-, and $2S$-wave states, and make a prediction of the mass spectrum for the tetraquark $ssbar{s}bar{s}$ system in the framework of a nonrelativistic potential quark model without the diquark-antidiquark approximation. The model parameters are well determined by our previous study of the strangeonium spectrum. We find that the resonances $f_0(2200)$ and $f_2(2340)$ may favor the assignments of ground states $T_{(ssbar{s}bar{s})0^{++}}(2218)$ and $T_{(ssbar{s}bar{s})2^{++}}(2378)$, respectively, and the newly observed $X(2500)$ at BESIII may be a candidate of the lowest mass $1P$-wave $0^{-+}$ state $T_{(ssbar{s}bar{s})0^{-+}}(2481)$. Signals for the other $0^{++}$ ground state $T_{(ssbar{s}bar{s})0^{++}}(2440)$ may also have been observed in the $phiphi$ invariant mass spectrum in $J/psitogammaphiphi$ at BESIII. The masses of the $J^{PC}=1^{--}$ $T_{ssbar{s}bar{s}}$ states are predicted to be in the range of $sim 2.44-2.99$ GeV, which indicates that the $phi(2170)$ resonance may not be a good candidate of the $T_{ssbar{s}bar{s}}$ state. This study may provide a useful guidance for searching for the $T_{ssbar{s}bar{s}}$ states in experiments.
A detailed discussion is given of the analysis of recent data to obtain improved upper bounds on the couplings $|U_{e4}|^2$ and $|U_{mu 4}|^2$ for a mainly sterile neutrino mass eigenstate $ u_4$. Using the excellent agreement among ${cal F}t$ values for superallowed nuclear beta decay, an improved upper limit is derived for emission of a $ u_4$. The agreement of the ratios of branching ratios $R^{(pi)}_{e/mu}=BR(pi^+ to e^+ u_e)/BR(pi^+ to mu^+ u_mu)$, $R^{(K)}_{e/mu}$, $R^{(D_s)}_{e/tau}$, $R^{(D_s)}_{mu/tau}$, and $R^{(D)}_{e/tau}$, and the branching ratios $BR(B^+rightarrow e^+ u_e)$ and $BR(B^+rightarrow mu^+ u_mu)$ decays with predictions of the Standard Model, is utilized to derive new constraints on $ u_4$ emission covering the $ u_4$ mass range from MeV to GeV. We also discuss constraints from peak search experiments probing for emission of a $ u_4$ via lepton mixing, as well as constraints from pion beta decay, CKM unitarity, $mu$ decay, leptonic $tau$ decay, and other experimental inputs.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
