17-20 June 2013
EST timezone

Program Advisory Committee Meeting - PAC40

December 14, 2012

PAC40 will be held during the week of June 17, 2013 and will continue the call for new nuclear physics proposals. The PAC will judge the technical and scientific aspects of submitted proposals and provide recommendations to Laboratory management. New proposals will be recommended for approval only if they represent high quality physics within the range of scientific importance represented by the previously approved 12 GeV proposals. The deadline for submission of proposals and updates is 8:00 a.m. EDT (Eastern Daylight Time) on Monday, May 6, 2013.

Proposals and updates for PAC40 should be submitted electronically using the instructions at http://www.jlab.org/exp_prog/PACpage/instructions.html

New Proposals

Detailed information on the process for proposal submission is available at http://www.jlab.org/exp_prog/PACpage/guidelines.html. New proposals will be granted a 20 minute presentation in a public session at the PAC meeting. Following the public presentation session the PAC will continue its discussions in closed session, and at least one spokesperson should be available either in person or by phone for 24 hours after the public session to answer questions as the PAC's discussion progresses. Proposals will, if approved, be given a scientific rating and a beamtime allocation.

In the past, proposals from Hall B that would run in parallel with previously approved proposals were separately considered by the PAC. Beginning with PAC40, the Hall B collaboration should submit proposals for complete run groups at one PAC meeting, where all of the anticipated physics associated with the proposed run group will be considered. Each run group can submit up to 4 individual proposals (up to 3 physics topics plus 1 summary of additional topics) and will be granted a maximum of 4 presentations corresponding to these proposals. New experimental proposals that run in parallel with previously approved run groups should be considered internally by the CLAS12 collaboration. A CLAS12 representative will have the opportunity to report on these to the PAC, and the PAC will then provide comments on them in its report. Proposed parallel running in other halls should be handled in a similar fashion.

Conditionally Approved Proposals

The PAC may conditionally approve proposals when additional requirements must be fulfilled before full approval is granted. There are two categories of conditional approval:

  • C2 - must return to the PAC to address concerns or issues to obtain approval,
  • C1 - must meet designated technical requirements to obtain approval from laboratory management – further PAC review is not required.

The rule for newly conditionally approved 12 GeV proposals is that they must return for approval at one of the next 2 consecutive PAC meetings following the PAC at which they received the conditional approval status.

Proposals that received C2 status at a previous PAC may return to PAC40 to be considered for approval. Proposals with previous conditional approval (C2) that wish to be considered for approval at PAC40 should submit an updated proposal and will be granted a 20-minute presentation at the PAC meeting. Following the public presentation session the PAC will continue its discussions in closed session, and at least one spokesperson should be available either in person or by phone for 24 hours after the public session to answer questions as the PAC's discussion progresses. If approved, the proposals will be considered for rating along with the other approved proposals in the grading session.

Prioritization

As the backlog of experiments is now quite substantial and there are several years before the experimental program is underway, we anticipate a need to discuss the process for establishing priorities in the future. PAC40 will continue a discussion of the process for re-establishing priorities of approved experiments on a timely basis.

Prioritization of Run Groups

There are a large number of experiments (currently only in Hall B) that have been organized into "run groups." Run groups include multiple experiments that can take data simultaneously on different and/or related physics using the same detector, target, and beam conditions. In addition to the individual experiment ratings reviews discussed above for the experiments within the run groups, we will carry out a review of the run groups themselves to establish their overall scientific priority. This will be done in a PAC session roughly one year before CLAS12 starts taking data. If similar situations evolve in the other halls we will do a similar "overall scientific priority" assignment to the run groups that evolve there.

PAC Results

The results of the PAC's deliberations will become public as follows: the list of scientific ratings and beam time allocations will be provided to the Hall Leaders at the PAC closeout and then posted on the PAC40 website within 24 hours. The final written PAC report will be posted on the PAC40 website and the user community notified by email as usual.

Appendix: Scientific Categories for Nuclear Physics Proposals

  1. The Hadron spectra as probes of QCD
    (GlueX and heavy baryon and meson spectroscopy)
  2. The transverse structure of the hadrons
    (Elastic and transition Form Factors)
  3. The longitudinal structure of the hadrons
    (Unpolarized and polarized parton distribution functions)
  4. The 3D structure of the hadrons
    (Generalized Parton Distributions and Transverse Momentum Distributions)
  5. Hadrons and cold nuclear matter
    (Medium modification of the nucleons, quark hadronization, N-N correlations, hypernuclear spectroscopy, few-body experiments)
  6. Low-energy tests of the Standard Model and Fundamental Symmetries
    (MOLLER, PVDIS, PRIMEX, ...)