Electromagnetic Radius of the Pion
40
Citation
8
Reference
10
Related Paper
Abstract:
The elastic differential scattering cross sections, as well as inelastic cross sections, have been obtained for both ${\ensuremath{\pi}}^{+}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}$ on ${\mathrm{He}}^{4}$ at 129, 140, and 150 $\frac{\mathrm{MeV}}{c}$, using a 50-cm helium bubble chamber. Following the suggestion of Sternheim and Hofstadter, we have analyzed these data in order to obtain the Coulomb-nuclear interference term. From this, the Coulomb amplitude is deduced, which gives information on the pion charge distribution. The data are analyzed in terms of (a) Born Coulomb amplitude containing a combined Gaussian form factor for the pion and the $\ensuremath{\alpha}$ particle, (b) pure nuclear phases, and (c) the distortion of the nuclear phases due to the long-range nature of the Coulomb field. These qualities, along with the corresponding nuclear potentials, suitably fitted to our data, are presented. We measure the rms combined radius of the pion-${\mathrm{He}}^{4}$ system as $R=1.1\ifmmode\pm\else\textpm\fi{}0.79$ F. This yields ${r}_{\ensuremath{\pi}}$, the rms radius for the pion, to be ${r}_{\ensuremath{\pi}}<0.9$ F.Keywords:
Charge radius
Form factor (electronics)
The HADES spectrometer installed at GSI Darmstadt is devoted to study the production of di-electron pairs from proton, pion and nucleus induced reactions at 1-2 AGeV. In pp collisions at 2.2 GeV we have focused mainly on exclusive reconstruction of the $\eta$ meson decays in the hadronic ($\eta\to\pi^{+}\pi^{-}\pi^{0}$) and the electromagnetic channels ($\eta\to e^{+}e^{-}\gamma$). We present analysis techniques and discuss first results on $\eta$ production, with the main focus on comparisons of reconstructed distributions to results obtained by other experiments and theoretical predictions.
Cite
Citations (3)
The elastic differential scattering cross sections, as well as inelastic cross sections, have been obtained for both ${\ensuremath{\pi}}^{+}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}$ on ${\mathrm{He}}^{4}$ at 129, 140, and 150 $\frac{\mathrm{MeV}}{c}$, using a 50-cm helium bubble chamber. Following the suggestion of Sternheim and Hofstadter, we have analyzed these data in order to obtain the Coulomb-nuclear interference term. From this, the Coulomb amplitude is deduced, which gives information on the pion charge distribution. The data are analyzed in terms of (a) Born Coulomb amplitude containing a combined Gaussian form factor for the pion and the $\ensuremath{\alpha}$ particle, (b) pure nuclear phases, and (c) the distortion of the nuclear phases due to the long-range nature of the Coulomb field. These qualities, along with the corresponding nuclear potentials, suitably fitted to our data, are presented. We measure the rms combined radius of the pion-${\mathrm{He}}^{4}$ system as $R=1.1\ifmmode\pm\else\textpm\fi{}0.79$ F. This yields ${r}_{\ensuremath{\pi}}$, the rms radius for the pion, to be ${r}_{\ensuremath{\pi}}<0.9$ F.
Charge radius
Form factor (electronics)
Cite
Citations (40)
Momentum (technical analysis)
Cite
Citations (3)
Momentum (technical analysis)
Cite
Citations (2)
Antiproton
Momentum (technical analysis)
Annihilation
Cite
Citations (79)
Annihilation
Momentum (technical analysis)
Electron–positron annihilation
Cite
Citations (30)
Fragmentation
Cite
Citations (13)
Charge radius
Form factor (electronics)
Cite
Citations (14)
Baryon number
Cite
Citations (1)
Parton shower
Momentum (technical analysis)
Cite
Citations (83)