View source for E+ White Paper Sub-Group


The physics program accessible to a positron beam at CEBAF energies is rich with a variety of possible experiments addressing the physics of different reaction channels: deeply virtual Compton scattering, two-photon exchange physics, potential physics scenarios beyond the Standard Model, and others processes where understanding would benefit of a comparison between electron and positron probes.

These different possibilities will be collected into a Positron White Paper (PWP) which will be made publicly  available by the PAC meeting. We are asking every person interested in the study of a specific physics channel with a positron beam at JLab, to contribute to the PWP with a description of their ideal experiment in no more than 4 pages. Proposals should expect a baseline of unpolarized positron beams with 1µA maximum intensity, and polarized positron beams with 100nA with a minimal polarization of 40%. As the conceptual design of the source and integration develop, efforts will be made to increase these values.

* Positron beam parameters

  Nominal design : 1µA unpolarized, 100nA 40% polarized.
  Very challenging design : 10µA unpolarized, 1µA 60% polarized.
  Momentum dispersion : dp/p~0.2%, similar to the regular electron beam.
  Emittance : 4-5 times larger than the regular electron beam. 

* Revised time table

  Final contribution: June 26th.
  First draft of the White Paper: July 3rd.
  Final Positron White Paper: July 17th.

= Deeply Virtual Compton Scattering =
''Coordinator: Silvia Niccolai (niccolai@ipno.in2p3.fr)''
* [[Contribution list - DVCS]]

= Two-Photon Exchange Physics =
''Coordinator: Axel Schmidt (schmidta@jlab.org)''
* [[Contribution list - TPE]]

= Physics Beyond the Standard Model =
''Coordinator: Marco Battaglieri (battagli@jlab.org)''
* [[Contribution list - PBSM]]

= Other Topics =
''Coordinator: Douglas Higinbotham (doug@jlab.org)''
* [[Contribution list - OT]]

= Document =
Provide your contribution to the Positron White Paper using the templates available at the link below. The main body of your contribution should not exceed 4 pages, excluding bibliography and the full list of authors and affiliations. Indicate leading authors at the appropriate place after the title. Authorship of the final Positron White Paper will gather all authors in one specific author list, with in addition the leading authors attached to each contribution. 

'''Send your contribution by the end of april to the coordinator of your sub-group.''' 

* Template files are [https://ipnshare.in2p3.fr/owncloud/index.php/s/BdDZ2NHS2qSV4jZ here]