• The proposal review committee (PRC) is an international committee advising the head of the division PSD on the distribution of user beamtime.
  • PRC members are appointed by the PSD director for a period of 3 years. An additional appointment of 3 years is possible. PSI pays for travel and accommodation expenses of the committee members.
  • The PRC splits into two committees for Protein crystallography (PX) and one for all other beamlines (Non-PX). The PSD director appoints one PRC member as chairperson for PX and Non-PX respectively.
  • All proposals are rated by the PRC. The rating is done in accordance with the IUPAP Recommendations for the Use of Major Physics Users Facilities, section 3.2) and is based on
    1. Scientific merit (relevance, impact, innovation, potential of the scientific- and/or technological case and/or relevance and applied importance of instrumental development)
    2. Technical feasibility
    3. Previous record of the proposers
    4. Availability of the resources required
  • Every proposal is rated by a minimum of 2 PRC members.

THE GRADING SCALE is 1.0 to 5.5:

  • 5.0-5.5: Outstanding proposal
  • 4.0-4.9: Excellent proposal
  • 3.0-3.9: Good proposal
  • 2.0-2.0: Sound proposal
  • 1.0-1.9: Rejected proposal
  • The PRC forms subcommittees to rate proposals belonging to individual beamlines and to similar scientific topics.
  • If a proposer asks for an unreasonable amount of beamtime, the PRC suggests how much beamtime is realistically needed.
  • If the feasibility of a proposal is uncertain, the PRC may change the proposal type to Test and suggest resubmission after successful completion of the test experiment.
  • In cases where the PRC has good reasons to expect synergies, it may suggest merging two proposals. The beamline manager asks the proposers if they agree with such a merger.
  • PRC-members absent themselves from the discussion of proposals in which they are proposers or co-proposers.
  • Following the ranking of the PRC and its recommendations, the BL managers draw up the list of experiments that are to receive beamtime during the next allocation period. Small adjustments of the allocated number of shifts may be necessary for logistic reasons.
  • The laboratory heads check for consistency in proposal acceptance and number of shifts across beamlines.
  • The head of the division PSD takes the final decision on proposal acceptance and shift allocation and distributes the reserved director’s time.
  • Proposers are informed about acceptance of their proposal, the rating and the type of proposal (long term, normal, pilot, and test).
  • The BL managers ask proposers for their scheduling preference and draw up the beamtime schedule, taking into account:
    1. facility operation conditions
    2. scheduling preferences by the users
  • If an experiment cannot be performed due to problems caused by the beam-line or the facility, it can be rescheduled using the reserve time (typically about 4 days at the end of the running period). The rescheduling decision is taken by the BL manager.