Related papers: $\eta$ and $\eta^\prime$ Physics at BES-III

We perform an improved perturbative QCD study of the decays $B_c^+ \to \eta_c L^+$,where $L$ denotes the light ground-state pseudoscalar, vector mesons and the corresponding $p$-wave scalar, axial-vector, and tensor ones, and predict their…

The lowest lying charmonium system $\eta_c$ has been observed for more than four decades. Studies of its production and decay properties provide an unique platform to investigate the inner structure of charmonium systems, hence improve our…

We report on the experimental search for the bound state of an $\eta$ meson and $^{3}\hspace{-0.03cm}\mbox{He}$ nucleus performed using the WASA-at-COSY detector setup. In order to search for the $\eta$-mesic nucleus decay, the…

We have computed the masses and decay constants of isotriplet $\pi_2(1670)$, the isoscalar $\eta_2(1645)$ and $\eta_2(1870)$ states as the ground-state nonet of $1^1D_2$ case within the Thermal QCD sum rules framework. This method is…

Charm hadronic decays are an important tool for understanding the the hadron spectroscopy and dynamics of the strong interaction in the low energy regime. BESIII experiment has collected a huge amount of data at various energy points around…

The radially excited pseudoscalar state $\eta(1295)$ is still poorly understood [as well as its $SU(3)$ partners $\pi(1300)$ and $K(1460 )$] and we want to attract attention experimenters to its comprehensive study. As for the main…

Masses and topological charges of the eta and eta' mesons are expressed in terms of the singlet-octet mixing angle theta. Contributions of the pseudoscalar 0- continuum are evaluated in a model independant way. Applications to the decay eta…

We measure the mass of the eta meson using psi(2S) --> eta J/psi events acquired with the CLEO-c detector operating at the CESR e+e- collider. Using the four decay modes eta --> gamma gamma, 3pi0, pi+pi-pi0, and pi+pi-gamma, we find…

Using the data samples of $1.31\times 10^9$ $J/\psi$ events and $4.48\times 10^8$ $\psi(3686)$ events collected with the BESIII detector, partial wave analyses on the decays $J/\psi$ and $\psi(3686) \to \pi^+\pi^-\eta^\prime$ are performed…

We report the first observation of $B\to \eta' X$ transitions with high momentum $\eta'$ mesons. We observe $39.0\pm 11.6$ B decay events with $2.0< p_{\eta'} < 2.7$ GeV/c, the high momentum region where background from $b\to c$ processes…

The processes $h_c\to\gamma P(P = \eta^\prime,~\eta,~\pi^0)$ are studied with a sample of $(27.12\pm0.14)\times10^{8}$ $\psi(3686)$ events collected by the BESIII detector at the BEPCII collider. The decay $h_{c}\rightarrow\gamma\eta$ is…

The studies on the multi-quark candidates, light scalar mesons and excited baryon states at BES are presented, based on $5.8 \times 10^7$ $J/\psi$ data collected with BESII detector. The measurements of some $J/\psi$ and $\eta_c$ decays are…

An analysis of the $J/\psi\to \eta\eta^\prime\gamma$ decay by the BESIII collaboration claims the observation of an exotic state $\eta_1(1855)$ with $I^GJ^{PC}=0^+1^{-+}$. To establish its C-parity partner $\eta^\prime_{1}(1855)$ in the…

Branching fraction ratios between the decays $B^{0}_{(s)} \rightarrow J/\psi \eta^{(\prime)}$ are measured using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of $7$, $8$ and $13~\textrm{TeV}$,…

Various decays of eta and eta-prime are investigated within the framework of U(3) chiral effective field theory in combination with a relativistic coupled-channels approach. Final state interactions are included by deriving s- and p-wave…

The $\eta$-$\eta^\prime$ pseudoscalar mixing angle and the gluonium content of the $\eta^\prime$ meson are deduced from an updated phenomenological analysis of $J/\psi$ decays into a vector and a pseudoscalar meson. The values for the…

The production of $\eta$ and $\eta'$ mesons is studied in proton-proton and proton-lead collisions collected with the LHCb detector. Proton-proton collisions are studied at center-of-mass energies of $5.02$ and $13~{\rm TeV}$, and…

The impact of new and highly precise neutron \b{eta} decay data is reviewed. We focus on recent results from neutron lifetime, \b{eta} asymmetry, and electron-neutrino correlation experiments. From these results, weak interaction parameters…

Using a sample of $448.1\times10^6$ $\psi(3686)$ events collected with the BESIII detector, we perform a study of the decay $\psi(3686) \rightarrow \phi \pi^{+}\pi^{-}\eta$. The branching fraction of $\psi(3686)\rightarrow\phi\eta^\prime$…

The octet-singlet $\eta -\eta^{\prime}$ mixing mass term could have a derivative $O(p^{2})$ term as found in recent analysis of the $\eta -\eta^{\prime}$ system. This term gives rise to an additional momentum-dependent pole contribution…