Exclusive and Diffraction

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• Mission Statement
  • The responsibilities of the Exclusive, Diffraction, and Tagging working group are to evaluate the performance of the ePIC detector as it relates to exclusive, diffractive, or tagging processes. We are charged with the development of a set of performance and physics benchmarks.
• Conveners
  • Zhoudunming Tu (zhoudunming@bnl.gov)
  • Raphael Dupré (raphael.dupre@ijclab.in2p3.fr)
• Contact and administrative info
  • Mailing list: eic-projdet-excldiff-l@lists.bnl.gov.
  • To subscribe, visit: https://lists.bnl.gov/mailman/listinfo/eic-projdet-excldiff-l.
  • Indico: https://indico.bnl.gov/category/419/
  • Mattermost: https://chat.epic-eic.org/main/channels/phys-exclusive-diffractive
  • Wiki: https://wiki.bnl.gov/EPIC/index.php?title=ExclusiveDiffractionTagging
• Meetings
  • Mondays at 12:00 pm ET (bi-weekly)

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Activities

Task List

• Implementation of benchmarks for all YR & proposal channels
  • Highest priority are DVCS and at least one tagged process
• Improve reconstruction in the FFwd region
  • Beam optics for various configurations
  • Treatment of more nuclei (He⁴ He³…)
• Study photon/π⁰ separation in calorimeters
  • Particularly implications for DVCS analyses

Benchmarks

• Diffractive Phi in eAu – see talk from K.Tu (10/23/23)

Ongoing Activities

• DVCS
  • Study on proton DVCS from O. Jevons (01/22/24)
• DVMP
  • π⁰ study from H.Jiang: [1] (04/08/24) and [2] (05/20/24)
  • J/ψ study from O. Olokunboyo (04/22/24)
  • J/ψ study from S. Fegan (05/13/24)
• Meson form factor
  • Study from L. Preet [1] (01/29/24) and [2] (04/22/24)
• Backward meson production
  • π⁰ on proton. See talks from Z.Sweger [1] (10/02/23) and [2] (01/29/24)
  • π⁰ and ρ study from Z.Sweger (04/22/24)
• Coherent VM production
  • J/ψ on A. See talk from Z.Citron, E.Mautner, M.Pitt [1] (09/18/23) and [2] (05/20/24)
  • ϕ on deuterium. See talk from A.Jentsch, K.Tu (09/11/23)
• Exclusive 𝛶 production
  • See talks from S.Yoo [1] (08/21/23) and [2] (04/29/24)
• Elastic ep
  • Study from B.Schmookler (04/29/24)

Detector oriented studies

• Impact of the B0 resolution
  • Talk from A.Jentsch (08/21/23)
  • Talk from Z.Sweger (05/13/24)
• Impact of the ZDC resolution
  • On π⁰ reconstruction see talk from Z.Sweger (11/06/23)
  • On reconstructing t in the ZDC see talk from B.Schmookler (01/22/24)

Simulations

• Google sheet with locations of output files from July simulation campaign
• Further instructions on accessing and analyzing the July sim files