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Precision studies at electron-positron colliders with center-of-mass energies in the charm-tau region and below have strongly contributed to our understanding of light-meson interactions at low energies. We focus on the processes involving two or three light mesons with invariant masses below nucleon-antinucleon threshold. A prominent role is given to the interactions of the nine lightest pseudoscalar mesons (pions, kaons, $\eta$, and $\eta'$) and the two narrow neutral isoscalar vector mesons $\omega$ and $\phi$. Experimental methods used to produce the mesons are reviewed as well as theory tools to extract properties of the meson-meson interactions. Examples of recent results from the DA$\Phi$NE, BEPCII, and VEPP-2000 colliders are presented. In the outlook we briefly discuss prospects for further studies at future super-charm-tau factories., Comment: 132 pages, 74 figures (v2: typos corrected, references updated, corresponds to the published version)

The world's largest sample of 1.31 billion $J/\psi$ events accumulated at the BESIII detector, provides a unique opportunity to investigate $\eta$ and $\eta^\prime$ physics via two body $J/\psi$ radiative or hadronic decays. For many $\eta^\prime$ decay channels the low background data samples are up to three orders of magnitude larger than collected in any previous experiment. Here we review the most significant results on $\eta$ and $\eta^\prime$ obtained at BESIII so far. The analyses range from detailed studies of the common decays dynamics, observations of new radiative and Dalitz decays, and search for rare/forbidden decays with sensitivity up to $\cal{B}\sim 10^{-5}$. Finally, prospects of the forthcoming runs at $J/\psi$ peak for the $\eta$ and $\eta^\prime$ physics are discussed., Comment: 17pages. 20 figures

The Time-Of-Flight system consisting of plastic scintillation counters plays an important role for particle identification in the BESIII experiment at the BEPCII double ring $e^+e^-$ collider. Degradation of the detection efficiency of the barrel TOF system has been observed since the start of physical data taking and this effect has triggered intensive and systematic studies about aging effects of the detector. The aging rates of the attenuation lengths and relative gains are obtained based on the data acquired in past several years. This study is essential for ensuring an extended operation of the barrel TOF system in optimal conditions., Comment: 14 pages, 8 figures

The light unflavoured meson $\eta/\eta^{\prime}$ decays are valuable for testing non-perturbative quantum chromodynamics and exploring new physics beyond the Standard Model. This paper describes a series of event generators, including $\eta/\eta^{\prime}\to\gamma l^{+}l^{-}$, $\eta/\eta^{\prime}\to\gamma \pi^{+}\pi^{-}$, $\eta^{\prime}\to\omega e^{+}e^{-}$, $\eta\to\pi^{+}\pi^{-}\pi^{0}$, $\eta/\eta^{\prime}\to\pi^{0}\pi^{0}\pi^{0}$, $\eta^{\prime}\to\eta\pi\pi$ and $\eta^{\prime}\to\pi^{+}\pi^{-}\pi^{+}\pi^{-}/\pi^{+}\pi^{-}\pi^{0}\pi^{0}$, which have been developed for investigating $\eta/\eta^\prime$ decay dynamics. For most of these generators, their usability has been validated in BESIII analyses for determining the detection efficiency, and background studies. The consistency between data and Monte Carlo shows that these generators work well in the BESIII simulation, and will also be useful for ongoing BESIII analyses and other experiments for studying $\eta/\eta^\prime$ physics.

We present physics opportunities and topics with the $s\bar{s}$ states (strangeonia) that can be studied with the BESIII detector operating at the BEPCII collider. Though the $\phi$ and $\eta/\eta^\prime$ states have long been established experimentally, only a handful of strangeonia are well known, in contrast to the rich $c\bar{c}$ charmoium system. An overview of the $s\bar{s}$ states and their experimental status is presented in this paper. The BESIII experiment has collected the world's largest samples of $J/\psi$, $\psi(2S)$, $\psi(3770)$, and direct $e^+e^-$ annihilations at energies below the $J/\psi$ and above 3.8\,GeV, and will continue to accumulate high quality, large integrated luminosity in the $\tau$-charm energy region. These data, combined with the excellent performance of the BESIII detector, will offer unprecedent opportunities to explore the $s\bar{s}$ system. In this paper we describe the experimental techniques to explore strangeonia with the BESIII detector.% at the BEPCII.

This paper introduces the calibration of the time-to-distance relation for the BESIII drift chamber. The parameterization of the time-to-distance relation is presented. The studies of left-right asymmetry and the variation with the entrance angle are performed. The impact of dead channels on the time-to-distance relation is given special attention in order to reduce the shifts of the measured momenta for the tracks passing near dead cells. Finally we present the spatial resolution (123 {\mu}m) for barrel Bhabha events (|cos{\theta}|<0.8) from J/{\psi} data taken in 2012.