Search results for "hadron"
showing 10 items of 3505 documents
"Table 1" of "Strange baryon production in Z hadronic decays"
1995
No description provided.
"Table 4" of "A Precise Determination of the Number of Families With Light Neutrinos and of the $Z$ Boson Partial Widths"
1990
No description provided.
"Table 10" of "Improved measurements of cross-sections and asymmetries at the Z0 resonance"
2000
No description provided.
"Table 1" of "Improved measurements of cross-sections and asymmetries at the Z0 resonance"
2000
No description provided.
Unveiling the strong interaction among hadrons at the LHC
2020
One of the key challenges for nuclear physics today is to understand from first principles the effective interaction between hadrons with different quark content. First successes have been achieved using techniques that solve the dynamics of quarks and gluons on discrete space-time lattices1,2. Experimentally, the dynamics of the strong interaction have been studied by scattering hadrons off each other. Such scattering experiments are difficult or impossible for unstable hadrons3–6 and so high-quality measurements exist only for hadrons containing up and down quarks7. Here we demonstrate that measuring correlations in the momentum space between hadron pairs8–12 produced in ultrarelativistic…
Study of Cluster Structures in Nuclei through the Ratio Method. A Tribute to Mahir Hussein
2020
For one-neutron halo nuclei, the cross sections for elastic scattering and breakup at intermediate energy exhibit similar angular dependences. The Recoil Excitation and Breakup (REB) model of reactions elegantly explains this feature. It also leads to the idea of a new reaction observable to study the structure of loosely-bound nuclear systems: the Ratio. This observable consists of the ratio of angular distributions for different reaction channels, viz. elastic scattering and breakup, which cancels most of the dependence on the reaction mechanism; in particular it is insensitive to the choice of optical potentials that simulate the projectile-target interaction. This new observable is very…
Combined description of N-barN scattering and annihilation with a hadronic model.
1995
A model for the nucleon-antinucleon interaction is presented which is based on meson-baryon dynamics. The elastic part is the {ital G}-parity transform of the Bonn {ital NN} potential. Annihilation into two mesons is described in terms of microscopic baryon-exchange processes including all possible combinations of {pi},{eta},{rho},{omega},{ital a}{sub 0},{ital f}{sub 0},{ital a}{sub 1},{ital f}{sub 1},{ital a}{sub 2},{ital f}{sub 2},{ital K},{ital K}{sup *}. The remaining annihilation part is taken into account by a phenomenological energy- and state-independent optical potential of Gaussian form. The model enables a simultaneous description of nucleon-antinucleon scattering and annihilatio…
πNscattering in relativistic baryon chiral perturbation theory reexamined
2011
We have analyzed pion-nucleon scattering using the manifestly relativistic covariant framework of infrared regularization up to $\mathcal{O}({q}^{3})$ in the chiral expansion, where $q$ is a generic small momentum. We describe the low-energy phase shifts with a similar quality as previously achieved with heavy baryon chiral perturbation theory, $\sqrt{s}\ensuremath{\lesssim}1.14$ GeV. New values are provided for the $\mathcal{O}({q}^{2})$ and $\mathcal{O}({q}^{3})$ low-energy constants, which are compared with previous determinations. This is also the case for the scattering lengths and volumes. Finally, we have unitarized the previous amplitudes and as a result the energy range where data …
Backward spin polarizabilityγπof the proton
2002
Using the Mainz $48\mathrm{cm}\ensuremath{\emptyset}\ifmmode\times\else\texttimes\fi{}64\mathrm{cm}$ NaI(Tl) detector and the segmented G\"ottingen recoil detector SENECA in coincidence, Compton scattering by the proton at ${\ensuremath{\theta}}_{\ensuremath{\gamma}}^{\mathrm{lab}}=136\ifmmode^\circ\else\textdegree\fi{}$ has been measured at MAMI (Mainz) in the energy range from 200 to 470 MeV. The new data confirm the previous observation that there is a systematic discrepancy between MAMI and LEGS (Brookhaven) data leading to different spin polarizabilities ${\ensuremath{\gamma}}_{\ensuremath{\pi}}=\ensuremath{-}38.7\ifmmode\pm\else\textpm\fi{}1.8$ and $\ensuremath{-}27.2\ifmmode\pm\else\…
Measurements of the Generalized Electric and Magnetic Polarizabilities of the Proton at LowQ2Using the Virtual-Compton-Scattering Reaction
2006
Experimental details of a virtual Compton scattering (VCS) experiment performed on the proton at the MIT-Bates out-of-plane scattering facility are presented. The VCS response functions ${P}_{LL}\ensuremath{-}{P}_{TT}/\phantom{{P}_{TT}\ensuremath{\varepsilon}}\ensuremath{\varepsilon}$ and ${P}_{LT}$ have been measured at ${Q}^{2}=0.057\phantom{\rule{0.28em}{0ex}}{\mathrm{GeV}}^{2}/{c}^{2}$. The generalized electric and magnetic polarizabilities, $\ensuremath{\alpha}({Q}^{2})$ and $\ensuremath{\beta}({Q}^{2})$, and the mean-square electric polarizability radius$\ensuremath{\langle}{r}_{\ensuremath{\alpha}}^{2}\ensuremath{\rangle}$ are obtained from a dispersion analysis of the data. The resu…