Related papers: M2 signatures in psi(2S) radiative decays
We report a new measurement of the exclusive electroproduction reaction gamma* p -> pi0 p to explore the evolution from soft non-perturbative physics to hard processes via the Q2 dependence of the magnetic (M1+), electric (E1+) and scalar…
We report new precise p$(\vec{e},e^\prime p)\pi^0$ measurements at the peak of the $\Delta^{+}(1232)$ resonance at $Q^2=\unit[0.20](GeV/c)^2$ performed at the Mainz Microtron (MAMI). The new data are sensitive to both the electric…
Using 53 pb$^{-1}$ of $e^+e^-$ annihilation data taken at $\sqrt{s}=3.686$ GeV, a comprehensive study has been made of the radiative decays of samples of 5.1 million $J/\psi$ and 24.5 million $\psi(2S)$ into pairs of pseudoscalar mesons,…
Microwave absorption spectra of a single square of two-dimensional electrons (2DES) have been investigated using an optical detection technique. Fundamental dipole and harmonic quadrupole plasmon modes have been identified and compared to…
Multipole analyses of the p(g,pi0), p(g,pi+) and p(g,g) reactions are carried out using different data sets. With sufficient constraints from polarization observables, the ratio of E2/M1 transition amplitudes for N->delta (EMR) appears to…
Some new results on magnetic dipole (M1) transitions in heavy quarkonium from nonrelativistic effective field theories of QCD are briefly reported. This model-independent approach not only facilitates a systematic and lucid way to…
We report a search for the decay psi(2S) -> gamma eta_c(2S) in a sample of 25.9 million psi(2S) events collected with the CLEO-c detector. No signals are observed in any of the 11 exclusive eta_c(2S) decay modes studied, or in their sum.…
Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon momentum spectrum in the decay J/psi->gamma+gluon+gluon, via the 'tagged' process: e+e- -> psi(2S); psi(2S)->J/psi…
We search for the hadronic decay $\eta_c(2S)\to 2(\pi^+\pi^-)$ in the $\psi(3686)\to\gamma\eta_c(2S)$ radiative decay using $(27.12\pm 0.14)\times 10^8$ $\psi(3686)$ events collected by the BESIII detector at the BEPCII collider. No…
Using our early experimental data on the cascade gamma-transitions from the 162Dy(n,2gamma) reaction, we determined dependence of the cascade intensity on the energy of their intermediate levels, and then - level density and radiatibe…
The new data on $\rho,\omega,\phi$ radiative decays into $\pi^0\gamma,\eta\gamma,\eta'\gamma$ from SND experiment at VEPP-2M $e^+e^-$ collider are presented.
Productions of scalar meson in the decays of J/\psi-->\omega+\sigma, J/\psi-->\gamma+\sigma and \psi(2s)-->\omega+\sigma, \gamma+\sigma and ee^+ annihilations in the regions of J/\psi and \psi(2s) are studied.
We estimate sensitivity coefficients Q_\mu to variation of the electron-to-proton mass ratio \mu for microwave transitions in partly deuterated ammonia NH2D and ND2H. Because of the mixing between rotational and inversion degrees of freedom…
The recent detections of electric-quadrupole (E2) transitions in water vapor and magnetic-dipole (M1) transitions in carbon dioxide have opened a new field in molecular spectroscopy. While in their present status, the spectroscopic…
The two-photon transition $\psi(3686)\to\gamma\gamma J/\psi$ is studied in a sample of 106 million $\psi(3686)$ decays collected by the BESIII detector. The branching fraction is measured to be…
The sums k(E1)+k(M1) of radiative strength functions of dipole primary gamma-transitions were approximated with high precision in the energy region of $0.5 < E_1 < B_n-0.5$ MeV for nuclei: 40K, 60Co, 71,74Ge, 80Br, 114Cd, 118Sn, 124,125Te,…
Using data accumulated with the CLEO detector corresponding to an integrated luminosity of 5.63 pb^-1 on the peak of the psi(2S) and 20.70 pb^-1 continuum at 3.67 GeV, we report first measurements of the branching fractions for the…
Using a sample of 3x10^6 psi(2S) decays recorded by the CLEO detector, we study three body decays of the chi_{c0}, chi_{c1}, and chi_{c2} produced in radiative decays of the psi(2S). We consider the decay modes pi+ pi- eta, K+ K- eta, p…
Based on $2.7 \times 10^9~\psi(3686)$ decays collected with the BESIII detector, the radiative decay $\psi(3686)\to\gamma2(\pi^{+}\pi^{-})\eta$ is investigated to measure properties of S- and P-wave charmonium states. The branching fraction…
Based on 14 million psi(2S) and 58 million J/psi events collected by the BESII detector, the leptonic decay of psi(2S) into $\tau^+\tau^-$, psi(2S) multi-body decays, chi_cJ decays, and J/psi hadronic decays are studied, and the branching…