Related papers: $\eta$ Meson Physics at Gem
Very recent data for the reaction gamma{d} --> eta{np} are analyzed within a model that includes contributions from the impulse approximation and next order corrections due to the np and eta{N} interactions in the final state. Comparison…
The fascinating physics underlying eta and eta-prime mesons can be studied theoretically and experimentally in various contexts. In this presentation we want to turn our attention to two important uncorrelated aspects of this vivid research…
One of the objectives of the vast physics programme of the recently comissioned WASA-at-COSY facility is the study of fundamental symmetries via the measurements of the eta and eta-prime mesons decays. Especially interesting are isospin…
We propose to investigate the in-medium properties of vector $\omega$ mesons at the normal nuclear density in Ap(pA) collisions and at higher density in AA collisions at the ITEP accelerator facility TWAC. Using of the inverse Ap kinematics…
The cross section for the production of $\omega$ mesons in proton-proton collisions has been measured in a previously unexplored region of incident energies. Cross sections were extracted at 92 MeV and 173 MeV excess energy, respectively.…
In this report the search for eta-mesic nuclei is reviewed. The brief description of the experimental studies is presented with a focus on the possible production of the eta-nucleus bound states for light nuclei like 4He and 3He.
The dynamics of $\eta$-meson production and the interaction of $\eta$-mesons with nucleons can be studied using the $\vec{p}p\to pp\eta$ reaction via measurements of the analyzing power $A_{y}$. To this end, we have performed a measurement…
I discuss the exciting prospects for exploring a wide range of new physics at a low-energy muon collider.
This report presents a review of the studies made in the working group on gamma gamma and e gamma physics" of the ECFA/DESY workshop on linear collider physics. It reports on several new physics studies, in particular s-channel Higgs…
We review the recent progress in the theoretical description and experimental observation of multiple parton interactions. Subjects covered include experimental measurements of minimum bias interactions and of the underlying event, models…
Recent results from HERA are presented on a range of topics: charged multiplicities, production of non-strange mesons and strange particles, charm fragmentation, baryons decaying to strange particles, antideuteron production, Bose-Einstein…
Nowadays the field of searching for a new physics became a very interesting subject in a light meson decays due to a recent results from KTeV collaboration which found the 3.3\sigma\ disagreement between Standard Model theory and their…
Coherent $\eta$ meson photoproduction on $^4$He and $^{12}$C is considered in the near-threshold region. The elementary $\eta$ photoproduction operator includes contributions from the $S_{11}(1535)$ and $D_{13}(1520)$ resonances as well as…
Experimental results on jet physics at LEP and SLC are reviewed and compared with perturbative QCD predictions. The discussion includes determinations of the strong coupling $\as$, measurements of event shape distributions and jet cross…
I review recent theory developments for hard exclusive and semi-exclusive production of mesons, emphasising the variety of physics issues that can be studied in these processes.
We discuss theoretically the possibility of observing the bound states of the \eta and \eta'(958) mesons in nuclei. We apply the NJL model to study the \eta and \eta' meson properties at finite density and calculate the formation cross…
An introduction to the physics of eta and eta' meson decays is given. A historical account of the discovery of the mesons is presented. It is followed by an overview and classification of the common decay modes and the relevance of the…
In a recent paper by the TAPS collaboration \cite{exp} a first measurement of a bound system of an $\eta$ meson and a ${^3}$He nucleus was reported. In this comment we critically reexamine the interpretation of the data and show that the…
We address the question of understanding the production of $J/\psi$ particles regarding the global underlying event in proton-proton collisions. To do so, we propose to look at a new observable: the $J/\psi$ production as a function of the…
First experimental results from a photoreaction which confirm an existence of eta-mesic nuclei are discussed. The experiment was performed at the 1 GeV electron synchrotron of LPI. Two values of the end-point energy of the bremsstrahlung…