Polarization Observables for Two-Pion Production off the Nucleon

Abstract

We develop polarization observables for the processes $\gamma N\to \pi \pi N$ and $\pi N\to \pi \pi N$, using both a helicity and hybrid helicity-transversity basis. Such observables are crucial if processes that produce final states consisting of a spin-1/2 baryon and two pseudoscalar mesons are to be fully exploited for baryon spectroscopy. We derive relationships among the observables, as well as inequalities that they must satisfy. We also discuss the observables that must be measured in `complete' experiments, and briefly examine the prospects for measurement of some of these observables in the near future.

20 pages, using revtex4

References in corpus (2)

• Spin Information from Vector-Meson Decay in Photoproduction
• Constraints on vector meson photoproduction spin observables

Cited by in corpus (41)

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• Photoproduction of pi0pi0 and pi0pi+-pairs off the proton from threshold to the second resonance region
• Beam-Helicity Asymmetries in Double Pion Photoproduction off the Proton
• Photoproduction of meson pairs: First measurement of the polarization observable I^s
• Electroproduction of p π^{+} π^{-} off protons at 0.2<Q^{2}<0.6 GeV^{2} and 1.3<W<1.57 GeV with CLAS
• Measurement of the beam-helicity asymmetry $I^{\odot }$ in the photoproduction of ${\pi }^0$-pairs off the proton and off the neutron
• First measurement of the circular beam asymmetry in the gamma p --> pi0 eta p reaction
• Moments of angular distribution and beam asymmetries in $\eta {\pi }^0$ photoproduction at GlueX
• Evaluation of the polarization observables I^S and I^C in the reaction gamma p --> pi^0 eta p
• Measurement of the beam-helicity asymmetry $I^{\odot }$ in the photoproduction of ${\pi }^0{\pi }^{\pm }$-pairs off protons and off neutrons
• Photoproduction ofeta-pi pairs off nucleons and deuterons
• Polarization observables in ${\pi }^0\eta$-photoproduction on the proton
• Moravcsik's theorem on complete sets of polarization observables reexamined
• Photon beam asymmetry $\Sigma$ in the reaction $\vec{\gamma }p\to p\omega$ for $E_{\gamma }$ = 1.152 to 1.876 GeV
• Charged pion photoproduction with the Delta(1232) baryon beyond the resonance region
• Complete set of observables for photoproduction of two pseudoscalars on a nucleon
• First measurement of target and beam-target asymmetries in the $\gamma p\to {\pi }^0\eta p$ reaction
• Minimal complete sets for two pseudoscalar meson photoproduction
• The complete experiment problem of pseudoscalar meson photoproduction in a truncated partial wave analysis
• Helicity-dependent cross sections for the photoproduction of ${\pi }^0$ pairs from nucleons
• First measurement of helicity-dependent cross sections in pi0-eta photoproduction from quasi-free nucleons
• On the background in the $\gamma p\to \omega ({\pi }^0\gamma )p$ reaction and mixed event simulation
• Theory of two-pion photo- and electroproduction off the nucleon
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• A Truncated partial wave analysis of a complete experiment for photoproduction of two pseudoscalar mesons on a nucleon
• Polarization observables in double neutral pion photoproduction
• Polarization Observables in $\gamma N\to K\bar{K}N$
• Helicity dependent cross sections for the photoproduction of ${\pi }^0{\pi }^{\pm }$ pairs from quasi-free nucleons
• Complete experiment problem for photoproduction of two pseudoscalar mesons on a nucleon in a truncated partial-wave analysis
• Quasi-free photoproduction of pion-pairs off protons and neutrons
• Baryon spectroscopy with polarization observables from CLAS
• Elliptical Polarization in Partial Wave Analysis of Two Spinless Meson Photoproduction
• New graphical criterion for the selection of complete sets of polarization observables and its application to single-meson photoproduction as well as electroproduction
• Angular Distributions, Polarization Observables, Spin Density Matrices and Statistical Tensors in Photoproduction of Two Pseudoscalar Mesons off a Nucleon
• Target and beam-target asymmetry measurements at MAMI