Related papers: Protonium: Discovery and Prediction
A search for heavy resonances decaying to a pair of Z bosons is performed using data collected with the CMS detector at the LHC. Events are selected by requiring two oppositely charged leptons (electrons or muons), consistent with the decay…
Decay rates of the positronium hydride PsH, a bound state of a proton, a positron, and two electrons, are determined for two rare channels, PsH $\to p^+ e^- \gamma$ and PsH $\to p^+ e^-$. Previous studies overestimated these rates by…
The pion decay constants of the lowest orbitally excited states of the nucleon and the $\Delta(1232)$ along with the corresponding axial transition form factors are calculated with Poincar\'e covariant constituent-quark models with instant,…
Because of the extreme smallness of the energy spread of the unstable state describing the decaying proton, due in its turn to the anomalous smallness of the resonance width expected for the proton decay, the application of the Heisenberg…
Exotic deuterium and helium are discussed. The S, P and D levels of antiprotonic and kaonic atoms are calculated. Absorptive, subthreshold antiproton-nucleon amplitudes are extracted from experimental data and compared to model…
Using a data sample of $(448.1\pm2.9)\times10^{6}$ $\psi(3686)$ decays collected by the BESIII detector at the Beijing Electron Positron Collider (BEPCII), we observe the decays $\chi_{cJ}\to \phi\phi\eta~(J=0,~1,~2)$, where the $\chi_{cJ}$…
Mesonic baryon resonance decays are calculated from constituent quark models along a Poincar\'e-invariant generalization of the elementary emission model. Covariant results of pionic decay widths are presented for the…
Three more $X$ particles are established in the 2014 Particle Data compared with the 2012 ones. There are now five established $X$ particles named as $X(3872)$, $X(3900)$, $X(4260)$, $X(4360)$, and $X(4660)$. Since the first $X$ particle…
In the framework of a scalar QFT, we evaluate the decay of an initial massive state into two massless particles through a triangle-shaped diagram in which virtual fields propagate. Under certain conditions, the decaying state can be seen as…
We investigate the region of the nuclear chart around $A \simeq 70$ from a three-body perspective, where we compute reaction rates for the radiative capture of two protons. One key quantity is here the photon dissociation cross section for…
A search for a new heavy scalar resonance decaying to two Z bosons, each subsequently decaying to a pair of electrons or muons, is presented. The results are based on a proton-proton collision data set collected by the CMS experiment at the…
It is proposed that meson resonances are linear combinations of q-qbar and meson-meson (MM); baryon resonances are combinations of qqq and meson-baryon (MB). Mixing between these combinations arises via decays of confined states to…
We study $S$-wave interactions of the baryon decuplet with the octet of pseudoscalar mesons using the lowest order chiral Lagrangian. We find two bound states in the SU(3) limit corresponding to the octet and decuplet representations. These…
The discovery and characteristics of transneptunian binaries are reviewed. In the 20 years since their first discovery, a wealth of detail has emerged including the frequency of binaries in different populations, their relative sizes and…
A list of searches is presented for massive resonances decaying to WW, WZ, ZZ, WH, ZH and HH boson pairs in proton-proton collision data collected by the CMS experiment at the LHC. The data are taken at centre-of-mass energies of 13TeV,…
We have studied the $^3P_J$ ($\chi_c)$ states of charmonium in formation by antiproton-proton annihilations in experiment E835 at the Fermilab Antiproton Source. We report new measurements of the mass, width, and $B(\chi_{cJ} \to \bar{p} p)…
Baryon number cumulants are invaluable tools to diagnose the primordial stage of heavy ion collisions if they can be measured. In experiments, however, proton number cumulants have been measured as substitutes. In fact, proton number…
Using a data sample collected with the BESIII detector operating at the BEPCII storage ring at a center-of-mass energy of $\sqrt{s}=4.600$ GeV, we search for the production of $e^{+}e^{-} \to \phi\chi_{c0,1,2}$ and the charmonium-like state…
A Poincare-invariant description of mesonic baryon resonance decays is presented following the point form of relativistic quantum mechanics. In this contribution we focus on pionic decay modes. It is found that the theoretical results in…
Hyperon physics offers a distinctive laboratory for probing the intensity frontier and searching for physics beyond the Standard Model. This review summarizes recent results from the BESIII experiment, including pioneering studies of dark…