As part of the ongoing Jefferson Lab Strategic Plan development, we held a Town Meeting on March 16, 2012, for users to bring their ideas and discuss the following issues:
- Vision for the Future (5 - 20+ years)
- Lost or missed opportunities ?
- Required New Initiatives ?
Here is a short summary: Several talks addressed necessary equipment upgrades to maximize the Physics output from experiments with 12 GeV beam in all 4 Halls:
- A PbWO4 forward calorimeter for Hall D to study rare eta decays (L. Gan)
- Modifications to the Hall B photon tagger to operate with 11 GeV beams, with the goal (among others) to hunt for possible “hidden” neutral scalar bosons (A. Gasparian)
- A transversely polarized H/D (ammonia or Lithium-hydride) DNP target for the rich program of TMDs and GPDs in Halls A and B (D. Crabb)
- A facility for polarized positrons needed to study form factors and GPDs (E. Voutier)
- A fast tracking trigger to increase the luminosity and reduce the data stream of large acceptance detectors like CLAS12 (M. Mestayer)
- A set of RICH counters for CLAS12 to achieve full particle identification over the relevant range of momenta to accomplish the complete study of TMDs and tagged structure functions over a wide kinematic range (P. Rossi)
- A combination of existing detectors for an optimized program of hypernuclear physics (L. Tang)
In addition, the talk by W. Melnitchouk pointed out the importance of measuring polarized structure functions of the neutron at large x without nuclear binding uncertainties, perhaps using polarized tritium targets or some kind of spectator tagging.
Stan Brodsky covered a wide range of possibly Physics topics with 12 GeV that should be studied and pursued if feasible; in particular he emphasized charm production.
Pawel Nadel-Turonski presented the case for a medium-energy, high luminosity electron-ion collider, which is being pursued as the next logical major project for Jefferson Lab.
Two remaining talks made the case for substantially different future facilities at the lab: An electron-electron collider for precision tests of the standard model and photon-photon fusion (C. Hyde) and a fixed-target, high energy program with 25-75 GeV beams (K. Hafidi).
See also http://wwwold.jlab.org/div_dept/physics_division/Physics_Town_Meeting.pdf for the previous town meeting held by the JLab Physics division in December 2011.