Measurement of the Polarized Structure Function ${\sigma }_{L{T}^{\prime }}$ for $p(\vec{e},e^{\prime }{\pi }^{+})n$ in the $\Delta (1232)$ Resonance Region

Abstract

The polarized longitudinal-transverse structure function ${\sigma }_{L{T}^{\prime }}$ has been measured using the $p(\vec{e},e^{\prime }{\pi }^{+})n$ reaction in the $\Delta (1232)$ resonance region at $Q^2=0.40$ and 0.65 GeV${}^2$. No previous ${\sigma }_{L{T}^{\prime }}$ data exist for this reaction channel. The kinematically complete experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. A partial wave analysis of the data shows generally better agreement with recent phenomenological models of pion electroproduction compared to the previously measured ${\pi }^{0}p$ channel. A fit to both ${\pi }^{0}p$ and ${\pi }^{+}n$ channels using a unitary isobar model suggests the unitarized Born terms provide a consistent description of the non-resonant background. The $t$-channel pion pole term is important in the ${\pi }^{0}p$ channel through a rescattering correction, which could be model-dependent.

6 pages, LaTex, 5 eps figures: Submitted to PRC/Brief Reports v2: Updated reference

References in corpus (16)

• A unitary isobar model for pion photo- and electroproduction on the proton up to 1 GeV
• $Q^2$ Dependence of Quadrupole Strength in the ${\gamma }^{\ast }p\to {\Delta }^{+}(1232)\to p{\pi }^0$ Transition
• Dynamical Study of the Delta Excitation in N(e,e' pi) Reactions
• Electroproduction of the Delta Resonance at High Momentum Transfer
• Dispersion Relation Constrained Partial Wave Analysis of piN Elastic and piN\to\etaN Scattering Data: The Baryon Spectrum
• Pion cloud and the $Q^2-$dependence of ${\gamma }^{\ast }N\leftrightarrow \Delta$ transition form factors
• Search for Quadrupole Strength in the Electro-excitation of the Delta(1232)
• Measurement of the recoil polarization in the p (\vec e, e' \vec p) pi^0 reaction at the Δ(1232) resonance
• Multipole Amplitudes of Pion Photoproduction on Nucleons up to 2GeV within Dispersion Relations and Unitary Isobar Model
• Measurement of the Polarized Structure Function ${\sigma }_{L{T}^{\prime }}$ for $p(\vec{e},e^{\prime }p){\pi }^o$ in the $\Delta (1232)$ Resonance Region
• QED Radiative Corrections in Processes of Exclusive Pion Electroproduction
• Measurement of the beam-helicity asymmetry in the p(e_pol,e'p)pi_0 reaction at the energy of the Delta(1232) resonance
• Measurement of the Transverse-Longitudinal Cross Sections in the p (e,e'p)pi0 Reaction in the Delta Region
• Induced proton polarization for pi^0 electroproduction at Q^2 = 0.126 (GeV/c)^2 around the Delta(1232) resonance
• Study of polarized-e polarized-p --> e-prime p pi0 in the Delta(1232) mass region using polarization asymmetries
• Measurement of the R${}_{LT}$ response function for ${\pi }^0$ electroproduction at $Q^2$ = 0.070 (GeV/c)${}^2$ in the $N\to \Delta$ transition}

Cited by in corpus (36)

• Unitary Isobar Model - MAID2007
• Progress Toward Understanding Baryon Resonances
• Electroexcitation of nucleon resonances from CLAS data on single pion electroproduction
• Electroexcitation of nucleon resonances
• A study of the $P_{11}(1440)$ and $D_{13}(1520)$ resonances from CLAS data on $ep\to e^{\prime }{\pi }^{+}{\pi }^{-}{p}^{\prime }$
• Electromagnetic Excitation of Nucleon Resonances
• New Results from the Studies of the $N(1440)1/2^{+}$, $N(1520)3/2^{-}$, and $\Delta (1620)1/2^{-}$ Resonances in Exclusive $ep\to e^{\prime }{p}^{\prime }{\pi }^{+}{\pi }^{-}$ Electroproduction with the CLAS Detector
• Electroexcitation of the P33(1232), P11(1440), D13(1520), S11(1535) at Q^2=0.4 and 0.65(GeV/c)^2
• Electroexcitation of the Roper resonance for 1.7 < Q2 < 4.5 GeV2 in ep -> enpi+
• Electroexcitation of nucleon resonances at Q^2=0.65 GeV/c^2 from a combined analysis of single- and double-pion electroproduction data
• Cross sections and beam asymmetries for $\vev{e}p \to enπ^+$ in the nucleon resonance region for $1.7\le Q^2\le 4.5(GeV{)}^2$
• Model Analysis of the $ep\to e{p}^{\prime }{\pi }^{+}{\pi }^{-}$ Electroproduction Reaction on the Proton
• Measurements of $ep\to e^{\prime }{\pi }^{+}n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS
• Empirical transverse charge densities in the nucleon-to-P11(1440) transition
• Strong QCD Insights from Excited Nucleon Structure Studies with CLAS and CLAS12
• Hadron structure at low Q^2
• Determination of quadrupole strengths in the gamma*p-->Delta(1232) transition at Q2= 0.20 (GeV/c)2
• 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
• Jülich-Bonn-Washington Model for Pion Electroproduction Multipoles
• Quark-Hadron Duality and Parity Violating Asymmetry of Electroweak Reactions in the Delta Region
• Baryon Resonance Analysis from MAID
• Results from the N* program at JLab
• Electroweak Form Factors of the $\Delta$(1232) Resonance
• Measurement of the Polarized Structure Function ${\sigma }_{L{T}^{\prime }}$ for Pion Electroproduction in the Roper Resonance Region
• First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)
• Coupled-channel analysis of pion- and eta-electroproduction with the Jülich-Bonn-Washington model
• Measurements of the γ* p --> Δ(1232) reaction at low Q2
• Electroexcitation of the ${\Delta }^{+}(1232)$ at low momentum transfer
• Electroexcitation of the Delta(1232)3/2+ and Delta(1600)3/2+ in a light-front relativistic quark model
• Virtual Compton Scattering measurements in the ${\gamma }^{\ast }N\to \Delta$ transition
• A dynamical model for pion electroproduction on the nucleon
• Measurement of Target and Double-spin Asymmetries for the $\vec{e}\vec{p}\to e{\pi }^{+}(n)$ Reaction in the Nucleon Resonance Region at Low $Q^2$
• Q^2-evolution of nucleon-to-resonance transition form factors in a QCD-inspired vector-meson-dominance model
• Two Photon Exchange for Exclusive Pion Electroproduction
• Measurement of the Partial Cross Sections s(TT), s(LT) and [s(T)+epsilon*s(L)] of the p(e,e' pi+)n Reaction in the Delta(1232) Resonance
• Pion electroproduction measurements in the nucleon resonance region