First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton

CLAS Collaboration

doi:10.1103/PhysRevLett.131.021901

First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton

CLAS Collaboration

Physics

Research output: Contribution to journal › Article › peer-review

Abstract

The polarized cross-section ratio σLT′/σ0 from hard exclusive π-Δ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV2 up to 7 GeV2. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ++ transition generalized parton distributions. A comparison to existing results for hard exclusive π+n and π0p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

Original language	English
Article number	021901
Number of pages	7
Journal	Physical Review Letters
Volume	131
Issue number	2
DOIs	https://doi.org/10.1103/PhysRevLett.131.021901
Publication status	Published - 11 Jul 2023

Bibliographical note

Funding Information:
We acknowledge the outstanding efforts of the staff of the Accelerator and the Physics Divisions at Jefferson Lab in making this experiment possible. We owe much gratitude to P. Kroll for many fruitful discussions concerning the interpretation of our results. This work was supported in part by the U.S. Department of Energy, the National Science Foundation (NSF), the Italian Istituto Nazionale di Fisica Nucleare (INFN), the French Centre National de la Recherche Scientifique (CNRS), the French Commissariat pour l’Energie Atomique, the UK Science and Technology Facilities Council, the National Research Foundation (NRF) of Korea, the Helmholtz-Forschungsakademie Hessen für FAIR (HFHF), the Deutsche Forschungsgemeinschaft (DFG), and the Chilean Agency of Research and Development (ANID). The Southeastern Universities Research Association (SURA) operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy under Contract No. DE-AC05-06OR23177.

Publisher Copyright:
© 2023 authors. Published by the American Physical Society.

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First Measurement of Hard Exclusive π − Δ+ + Electroproduction Beam-Spin Asymmetries off the Proton
© 2023 authors.
Final published version, 672 KBLicence: CC BY

Cite this

@article{548a1ebb06be4c5c8266d309338a939c,

title = "First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton",

abstract = "The polarized cross-section ratio σLT′/σ0 from hard exclusive π-Δ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV2 up to 7 GeV2. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ++ transition generalized parton distributions. A comparison to existing results for hard exclusive π+n and π0p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.",

author = "{CLAS Collaboration} and S. Diehl and N. Trotta and K. Joo and P. Achenbach and Z. Akbar and Armstrong, {W. R.} and H. Atac and H. Avakian and L. Baashen and Baltzell, {N. A.} and L. Barion and M. Bashkanov and M. Battaglieri and I. Bedlinskiy and F. Benmokhtar and A. Bianconi and Biselli, {A. S.} and F. Boss{\`u} and Brinkmann, {K. T.} and Briscoe, {W. J.} and D. Bulumulla and V. Burkert and R. Capobianco and Carman, {D. S.} and Carvajal, {J. C.} and A. Celentano and G. Charles and P. Chatagnon and V. Chesnokov and G. Ciullo and Cole, {P. L.} and M. Contalbrigo and G. Costantini and V. Crede and A. D'Angelo and N. Dashyan and {De Vita}, R. and A. Deur and C. Djalali and R. Dupre and M. Ehrhart and {El Alaoui}, A. and {El Fassi}, L. and L. Elouadrhiri and S. Fegan and A. Filippi and G. Gavalian and Glazier, {D. I.} and Watts, {D. P.} and N. Zachariou",

note = "Funding Information: We acknowledge the outstanding efforts of the staff of the Accelerator and the Physics Divisions at Jefferson Lab in making this experiment possible. We owe much gratitude to P. Kroll for many fruitful discussions concerning the interpretation of our results. This work was supported in part by the U.S. Department of Energy, the National Science Foundation (NSF), the Italian Istituto Nazionale di Fisica Nucleare (INFN), the French Centre National de la Recherche Scientifique (CNRS), the French Commissariat pour l{\textquoteright}Energie Atomique, the UK Science and Technology Facilities Council, the National Research Foundation (NRF) of Korea, the Helmholtz-Forschungsakademie Hessen f{\"u}r FAIR (HFHF), the Deutsche Forschungsgemeinschaft (DFG), and the Chilean Agency of Research and Development (ANID). The Southeastern Universities Research Association (SURA) operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy under Contract No. DE-AC05-06OR23177. Publisher Copyright: {\textcopyright} 2023 authors. Published by the American Physical Society. ",

year = "2023",

month = jul,

day = "11",

doi = "10.1103/PhysRevLett.131.021901",

language = "English",

volume = "131",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "2",

}

TY - JOUR

T1 - First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton

AU - CLAS Collaboration

AU - Diehl, S.

AU - Trotta, N.

AU - Joo, K.

AU - Achenbach, P.

AU - Akbar, Z.

AU - Armstrong, W. R.

AU - Atac, H.

AU - Avakian, H.

AU - Baashen, L.

AU - Baltzell, N. A.

AU - Barion, L.

AU - Bashkanov, M.

AU - Battaglieri, M.

AU - Bedlinskiy, I.

AU - Benmokhtar, F.

AU - Bianconi, A.

AU - Biselli, A. S.

AU - Bossù, F.

AU - Brinkmann, K. T.

AU - Briscoe, W. J.

AU - Bulumulla, D.

AU - Burkert, V.

AU - Capobianco, R.

AU - Carman, D. S.

AU - Carvajal, J. C.

AU - Celentano, A.

AU - Charles, G.

AU - Chatagnon, P.

AU - Chesnokov, V.

AU - Ciullo, G.

AU - Cole, P. L.

AU - Contalbrigo, M.

AU - Costantini, G.

AU - Crede, V.

AU - D'Angelo, A.

AU - Dashyan, N.

AU - De Vita, R.

AU - Deur, A.

AU - Djalali, C.

AU - Dupre, R.

AU - Ehrhart, M.

AU - El Alaoui, A.

AU - El Fassi, L.

AU - Elouadrhiri, L.

AU - Fegan, S.

AU - Filippi, A.

AU - Gavalian, G.

AU - Glazier, D. I.

AU - Watts, D. P.

AU - Zachariou, N.

N1 - Funding Information: We acknowledge the outstanding efforts of the staff of the Accelerator and the Physics Divisions at Jefferson Lab in making this experiment possible. We owe much gratitude to P. Kroll for many fruitful discussions concerning the interpretation of our results. This work was supported in part by the U.S. Department of Energy, the National Science Foundation (NSF), the Italian Istituto Nazionale di Fisica Nucleare (INFN), the French Centre National de la Recherche Scientifique (CNRS), the French Commissariat pour l’Energie Atomique, the UK Science and Technology Facilities Council, the National Research Foundation (NRF) of Korea, the Helmholtz-Forschungsakademie Hessen für FAIR (HFHF), the Deutsche Forschungsgemeinschaft (DFG), and the Chilean Agency of Research and Development (ANID). The Southeastern Universities Research Association (SURA) operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy under Contract No. DE-AC05-06OR23177. Publisher Copyright: © 2023 authors. Published by the American Physical Society.

PY - 2023/7/11

Y1 - 2023/7/11

N2 - The polarized cross-section ratio σLT′/σ0 from hard exclusive π-Δ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV2 up to 7 GeV2. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ++ transition generalized parton distributions. A comparison to existing results for hard exclusive π+n and π0p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

AB - The polarized cross-section ratio σLT′/σ0 from hard exclusive π-Δ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV2 up to 7 GeV2. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ++ transition generalized parton distributions. A comparison to existing results for hard exclusive π+n and π0p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

UR - http://www.scopus.com/inward/record.url?scp=85165014529&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.131.021901

DO - 10.1103/PhysRevLett.131.021901

M3 - Article

C2 - 37505937

AN - SCOPUS:85165014529

SN - 0031-9007

VL - 131

JO - Physical Review Letters

JF - Physical Review Letters

IS - 2

M1 - 021901

ER -

First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton

Abstract

Bibliographical note

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Nuclear Physics Consolidated Grant 2021-2024

Cite this

First Measurement of Hard Exclusive π- Δ++ Electroproduction Beam-Spin Asymmetries off the Proton

Abstract

Bibliographical note

Access to Document

Other files and links

Projects

Nuclear Physics Consolidated Grant 2021-2024

Cite this