相关论文: First observation of long-lived $\pi^+ \pi^-$ atom…
The ^1{\Sigma}^+ electronic ground states of MgLi^+ and CaLi^+ molecular ions are investigated for their spectroscopic constants and properties such as the dipole- and quadrupole moments, and static dipole polarizabilities. The quadrupole…
An experimental observation of proton decay would be a spectacular proof of grand unification. Currently, the best constraint on the proton lifetime for the p->e+ pi0 decay channel, coming from the Super-Kamiokande experiment, reaches…
When the atoms of a dimer remain most of the time very far apart, in so-called long-range molecular states, their mutual interaction is ruled by plain atomic properties. The high-resolution spectroscopic study of some molecular excited…
We have measured the lifetime of the 5s5p ^3P_2 metastable state of strontium atoms by magneto-optically trapping the decayed atoms to the ground state, which allowed sensitive detection of the rare decay events. We found that the blackbody…
Long-lived high-spin super- and hyper-deformed isomeric states, which exhibit themselves by abnormal radioactive decays, have been observed using the 16O + 197Au and 28Si + 181Ta reactions. They make it possible to understand the…
We report lifetime measurements of the metastable $6\mathrm{d}\, ^{2}\mathrm{D}_{5/2}$ and $6\mathrm{d}\, ^{2}\mathrm{D}_{3/2}$ states of Ra$^+$. The measured lifetimes, $\tau_{5} = $ 303.8(1.5) ms and $\tau_{3} = $ 642(9) ms, are important…
A review of the modern theory of hadronic atoms based on the non-relativistic effective Lagrangian approach and ChPT, is given. As an application of the general framework, we consider the decay of the pi+pi- atom into two neutral pions, and…
The PHENIX experiment, has recently acquired $\sim$ 1 billion minimum bias Au+Au events at $\sqrt s = 200$GeV during the year-2004 run. This high statistics data set, coupled with a state-of-the-art analysis technique, allows for the…
The strong interaction shift and broadening in pionic deuterium have been remeasured with high statistics by means of the (3p-1s) X-ray transition using the cyclotron trap and a high-resolution crystal spectrometer. Preliminary results are…
A study of the sensitivity of the CLIC ILD detector model for massive long-lived particles produced in the decay of the Higgs boson is presented, using a data sample of $e^+e^-$ collisions at centre-of-mass energy of 350 GeV and 3 TeV,…
An unusual but effective way to determine at threshold the dpi -> NN transition strength is to exploit the hadronic ground-state broadening in pionic deuterium, accessible by x-ray spectroscopy. The broadening is dominated by the true…
The perturbative framework is developed for the calculation of the pi(+)pi(-) atom characteristics (energy level shift and lifetime) on the basis of the field-theoretical Bethe-Salpeter approach. A closed expression for the first-order…
A partial wave analysis of the process $\psi(2S)\rightarrow\gamma\chi_{c1}, \chi_{c1}\rightarrow\pi^+\pi^-\eta^{\prime}$ is performed using $(2712.4\pm14.3)\times10^{6}$ $\psi(2S)$ events collected with the BESIII detector. An isovector…
We present a combined experimental and theoretical study on the radiative lifetime of CO in the $a^3\Pi_{1,2}, v=0$ state. CO molecules in a beam are prepared in selected rotational levels of this metastable state, Stark-decelerated and…
Time resolved detection of laser induced fluorescence from pulsed excitation of electronic states in barium monofluoride (BaF) molecules has been performed in order to determine the lifetimes of the $A^2\Pi_{1/2}$ and $A^2\Pi_{3/2}$ states.…
The lifetimes of first excited 2$^+$, 4$^+$ and 6$^+$ states in $^{98}$Zr were measured with the Recoil-Distance Doppler Shift method in an experiment performed at GANIL. Excited states in $^{98}$Zr were populated using the fission reaction…
The results of the measurements of the double-differential production cross-sections of pions in p-C and $\pi^\pm$-C interactions using the forward spectrometer of the HARP experiment are presented. The incident particles are 12 GeV/c…
The COMPASS experiment at CERN has collected a large data sample of 50 million diffractively produced $\pi^-\pi^+\pi^-$ events using a $190\,$GeV$/c$ negatively charged hadron beam. The partial-wave analysis (PWA) of these high-precision…
A precise determination of the charm-strange baryon Cascade(c)+ lifetime is presented. The data were accumulated by the Fermilab high-energy photoproduction experiment FOCUS. The measurement is made with 300 Cascade(c)+ --> Cascade- pi+ pi+…
In heavy nuclei the spatial distribution of protons and neutrons is different. At CERN SPS energies production of $\pi^+$ and $\pi^-$ differs for $pp$, $pn$, $np$ and $nn$ scattering. These two facts lead to an impact parameter dependence…