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First results on nucleon resonance electroexcitation amplitudes from ep → e'π+πp' cross sections at W = 1.4–1.7 GeV and Q2 = 2.0–5.0 GeV2

Journal Article · · Physical Review. C
 [1];  [2];  [2];  [2];  [3];  [4];  [5];  [6];  [3];  [3]
  1. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Thomas Jefferson National Accelerator Facility
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  3. University of South Carolina, Columbia, SC (United States)
  4. Tübingen University (Germany)
  5. Moscow State University (Russia)
  6. University of Connecticut, Storrs, CT (United States)
The electroexcitation amplitudes or $$\gamma_vpN^*$$ electrocouplings of the $N(1440)1/2^+$, $N(1520)3/2^-$, and $$\Delta(1600)3/2^+$$ resonances were obtained for the first time from the $$ep \to e'\pi^+\pi^-p'$$ differential cross sections measured with the CLAS detector at Jefferson Lab within the range of invariant mass $$W$$ of the final state hadrons from 1.4–1.7~GeV for photon virtualities $Q^2$ from 2.0--5.0~GeV$^2$. A good description of the nine independent one-fold differential $$\gamma_v p\to \pi^+\pi^-p'$$ cross sections achieved within the data-driven Jefferson Lab-Moscow State University (JM) meson-baryon reaction model in each bin of ($$W$$,$Q^2$) allows for separation of the resonant and non-resonant contributions. The electrocouplings were determined in the fits of the $$\pi^+\pi^-p$$ cross sections within three overlapping $$W$$ intervals with a substantial contribution from each of the three resonances listed above. Consistent results on the electrocouplings extracted from the data in these $$W$$ intervals provide evidence for their reliable extraction. These studies extend information on the electrocouplings of the $N(1440)1/2^+$ and $N(1520)3/2^-$ available from this channel over a broader range of $Q^2$. The electrocouplings of the $$\Delta(1600)3/2^+$$, which decays preferentially into $$\pi\pi N$$ final states, have been determined for the first time. Here, the reliable extraction of the electrocouplings for these states is also supported by the description of the $$\pi^+\pi^-p$$ differential cross sections with $Q^2$-independent masses and total/partial hadronic decay widths into the $$\pi\Delta$$ and $$\rho p$$ final states.
Research Organization:
Accelerator Facility (TJNAF), Newport News, VA (United States); Thomas Jefferson National Accelerator Facility; Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Organization:
National Science Foundation (NSF); USDOE Office of Science (SC)
Grant/Contract Number:
AC05-06OR23177
OSTI ID:
1996745
Alternate ID(s):
OSTI ID: 1996966
Report Number(s):
DOE/OR/23177-6506; JLAB-PHY-23-3865
Journal Information:
Physical Review. C, Journal Name: Physical Review. C Journal Issue: 2 Vol. 108; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (70)

Nucleon and $${\Delta}$$ Δ Elastic and Transition Form Factors journal October 2014
Electromagnetic $${\varvec{N}}^{\varvec{*}}$$ N ∗ Transition Form Factors in the ANL-Osaka Dynamical Coupled-Channels Approach journal March 2018
Electroexcitation of Nucleon Resonances in a Light-Front Relativistic Quark Model journal June 2018
Measurement of New Observables from the $$\pi ^{+}\pi ^{-}p$$ π + π - p Electroproduction Off the Proton: Reaction: $$ep \rightarrow e'p'\pi ^{+}\pi ^{-}$$ e p → e ′ p ′ π + π - $$Q^{2}=[2.0, 5.0]$$ Q 2 = [ 2.0 , 5.0 ] GeV2 $$W=[1.400, 2.125]$$ W = [ 1.400 , 2.125 ] GeV journal November 2018
Strong QCD Insights from Excited Nucleon Structure Studies with CLAS and CLAS12 journal August 2020
Photo- and Electrocouplings of Nucleon Resonances journal July 2022
On mass and matter journal March 2021
The K-matrix formalism for overlapping resonances journal July 1972
Quark models of baryon masses and decays journal January 2000
The CEBAF large acceptance spectrometer (CLAS)
  • Mecking, B. A.; Adams, G.; Ahmad, S.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 503, Issue 3 https://doi.org/10.1016/S0168-9002(03)01001-5
journal May 2003
The structure of the Roper resonance journal January 2001
First results on nucleon resonance photocouplings from the γp → π+π−p reaction journal January 2019
Evidence for the N′(1720)3/2+ nucleon resonance from combined studies of CLAS π+π−p photo- and electroproduction data journal June 2020
Electroexcitation of nucleon resonances journal January 2012
Diquark correlations in hadron physics: Origin, impact and evidence journal January 2021
Insights into the emergence of mass from studies of pion and kaon structure journal September 2021
N* Experiments and what they tell us about Strong QCD Physics journal January 2020
Form factors for the Nucleon-to-Roper electromagnetic transition at large-Q2 journal January 2020
Two Pion Photo- and Electroproduction with CLAS journal January 2020
The pion: an enigma within the Standard Model journal May 2016
Review of Particle Physics journal August 2022
Nucleon resonance contributions to unpolarized inclusive electron scattering journal September 2019
Exclusive π 0 p electroproduction off protons in the resonance region at photon virtualities 0.4 GeV 2 ≤ Q 2 ≤ 1 GeV 2 journal January 2020
Jülich-Bonn-Washington model for pion electroproduction multipoles journal June 2021
Resonant contributions to inclusive nucleon structure functions from exclusive meson electroproduction data journal August 2021
Polarized structure function σLT′ from π0p electroproduction data in the resonance region at 0.4GeV2<Q2<1.0GeV2 journal February 2022
Coupled-channels analysis of pion and η electroproduction within the Jülich-Bonn-Washington model journal July 2022
Resonant contributions to polarized proton structure functions journal March 2023
What is the structure of the Roper resonance? journal July 2000
Multipole amplitudes of pion photoproduction on nucleons up to 2 GeV using dispersion relations and the unitary isobar model journal January 2003
Electroexcitation of nucleon resonances at Q 2 = 0 . 65 ( GeV / c ) 2 from a combined analysis of single- and double-pion electroproduction data journal October 2005
Electroproduction of p π + π − off protons at 0 . 2 < Q 2 < 0 . 6 GeV 2 and 1 . 3 < W < 1 . 57 GeV with the CLAS detector journal January 2009
Dynamical coupled-channels study of π N → π π N reactions journal February 2009
π + photoproduction on the proton for photon energies from 0.725 to 2.875 GeV journal June 2009
Model analysis of the ep → e ' p π + π − electroproduction reaction on the proton journal October 2009
Electroexcitation of nucleon resonances from CLAS data on single pion electroproduction journal November 2009
Extraction of electromagnetic transition form factors for nucleon resonances within a dynamical coupled-channels model journal October 2010
Nucleon electromagnetic form factors and electroexcitation of low-lying nucleon resonances in a light-front relativistic quark model journal May 2012
Experimental study of the P 11 ( 1440 ) and D 13 ( 1520 ) resonances from the CLAS data on e p → e ′ π + π − p ′ journal September 2012
Electromagnetic transition form factors of the Roper resonance in a phenomenological field theory journal July 2014
Measurements of e p → e ′ π + n at 1.6 < W < 2.0  GeV and extraction of nucleon resonance electrocouplings at CLAS journal April 2015
Extracting meson-baryon contributions to the electroexcitation of the N ( 1675 ) 5 2 − nucleon resonance journal July 2015
New results from the studies of the N ( 1440 ) 1 / 2 + ,   N ( 1520 ) 3 / 2 − , and Δ ( 1620 ) 1 / 2 − resonances in exclusive e p → e ′ p ′ π + π − electroproduction with the CLAS detector journal February 2016
Measurements of e p → e ′ π + π − p ′ cross sections with CLAS at 1.40 GeV < W < 2.0 GeV and 2.0 GeV 2 < Q 2 < 5.0 GeV 2 journal August 2017
Measurements of the γ v p → p ′ π + π − cross section with the CLAS detector for 0.4 GeV 2 < Q 2 < 1.0 GeV 2 and 1.3 GeV < W < 1.825 GeV journal August 2018
Transition form factors: γ * + p → Δ ( 1232 ) , Δ ( 1600 ) journal August 2019
Spectrum and structure of octet and decuplet baryons and their positive-parity excitations journal September 2019
Transition form factors and helicity amplitudes for electroexcitation of negative and positive parity nucleon resonances in a light-front quark model journal November 2019
Nucleon resonances with higher spins in soft-wall AdS/QCD journal November 2020
Composition of low-lying J=32± Δ -baryons journal June 2022
Wave functions of (I,JP)=(12,32∓) baryons journal January 2023
Unitary analytic isobar model for the reaction nucleon-meson to nucleon-meson-meson journal June 1978
Medium-energyNππdynamics. I journal September 1979
Multichannel resonance parametrization of π N scattering amplitudes journal June 1992
Baryon current matrix elements in a light-front framework journal April 1995
Masses and widths of N and Δ resonances journal May 1995
Electroproduction of the Roper resonance on the proton: The role of the three-quark core and the molecular N σ component journal July 2011
Excited state baryon spectroscopy from lattice QCD journal October 2011
Structure of the nucleon’s low-lying excitations journal February 2018
Disentangling the Dynamical Origin of P 11 Nucleon Resonances journal January 2010
Completing the Picture of the Roper Resonance journal October 2015
Where Have All the Resonances Gone? An Analysis of Baryon Couplings in a Quark Model with Chromodynamics journal March 1980
Measurement of e p → e ′ p π + π − and Baryon Resonance Analysis journal July 2003
Baryon spectroscopy journal April 2010
Colloquium : Roper resonance: Toward a solution to the fifty year puzzle journal March 2019
Studies of Nucleon Resonance Structure in Exclusive Meson Electroproduction journal June 2013
Strong QCD from Hadron Structure Experiments journal August 2020
Nucleon Resonance Electroexcitation Amplitudes and Emergent Hadron Mass journal March 2023
Empirical Consequences of Emergent Mass journal September 2020
The Hypercentral Constituent Quark Model and Its Application to Baryon Properties journal January 2015