CHESS typically provides beamtime to users for 125 days per year distributed over three cycles. Users can apply for beamtime each cycle through general user proposals and beamtime requests (BTRs) in the web-based User Portal system as described below.
Prospective Users Handbook
Planning Your Experiment and Understanding Beamline Capabilities
Look at the Beamline capabilities webpage. Determine which beamline and technique best fits your experimental needs. If you have questions contact a Staff Scientist to discuss your research (the CHESS User Office will also get you in touch with the appropriate Staff Scientist):
- What is the research problem?
- Which station(s) are appropriate?
- How mature is the research project (risk, size)? Has this been tried on a home source?
- What is the material - sample composition, form, size, availability?
- What are the experimental conditions (temperature, pressure, etc.)?
- What will be measured?
- Probability of success? Impact? Significance?
- How will results be presented and to whom?
- What is the timeline?
Proposal Types
There is one proposal submission form in the CHESS user data base (User Portal) for two proposal types:
General User Proposals for FAST, QM2, PIPOXS, HPBioSAXS, FlexX.
Submission: Proposals and beam time requests (BTRs) submitted for three proposal cycles every year (see “Deadlines”)
Amount of beam time requested: Any amount of beam time (Allocations of 9-18 shifts are typical)
Proposed Research: Experiments aligned with the research focus of the beamlines
Review: Scientific merit of proposals scored by external reviewers
Feasibility and safety reviewed by CHESS staff
Beam time Allocation: By beamtime allocation committee based on proposal scores
Scheduling: Beam time scheduled for entire cycle before cycle starts
Rapid Access Proposals for BioSAXS, FlexX.
Submission: Proposals and beamtime requests (BTRs) submitted anytime
Amount of beam time requested: Short beam times, typically 3-6 shifts.
Proposed Research: Samples available or can be made on short notice;
Experiments aligned with the research focus of the beamlines
Review: Scientific merit of proposals scored by external reviewers
Feasibility and safety reviewed by CHESS staff
Within 2 weeks of submission
Beam Time Allocation: By beam time allocation committee based on proposal scores
Scheduling: Continuous; Beam time available for Rapid Access Proposals every month
For Rapid Access Proposals the proposal title should start with “Rapid Access: …”
How to Submit a Proposal in User Portal
Once you have determined the details of your experiment and the beamline you wish to use you are ready to begin the proposal process:
- Go to the User Portal, register as a new user, and create a profile.
- You will now see the main dashboard of the User Portal
- Upper left corner of your dashboard select "My Proposals"
- Then select "New Proposal"
- After you have entered the title of the proposal you will then see the 10 different sections of the proposal
- Please remember when filling out the proposal that this will be peer-reviewed by an outside group of reviewers and safety reviewed. See guidelines for writing a successful proposal. Step-by-step instructions can be found in the User Portal.
Proposal Review and Scoring
How is my proposal peer reviewed?
- A peer review is conducted on your proposal by outside reviewers (2-3) and an average final score will be assigned to the proposal upon completion of the review(s). Your average score will be on a scale of 1-4, 1 being excellent and 4 being poor. The areas in which your proposal will be scored are:
- Scientific and or Technical Merit
- Need for CHESS Capabilities
- Experimental Plan Details
- Expertise of Group (in both x-ray methods and science subject areas)
Below is a snapshot of the reviewer score sheet:
Scientific and/or Technical Merit
- Excellent - Results will be considered impactful and important - ambitious and innovative
- Very Good - Will advance scientific knowledge, methods, and/or address critical questions
- Good - Research contributes to scientific and/or technical knowledge base
- Poor - Proposed research has no clear importance or originality
Need for CHESS Capabilities
- Excellent - CHESS facilities and capabilities essential to obtain experimental results
- Very Good - Well documented need for existing facilities and capabilities
- Good - Appropriate use of existing facilities and capabilities
- Poor - Routine use of existing facilities and methods or poorly demonstrated need
Experimental Plan Details
- Thorough - Uses established facilities/methods or addresses all phases of a successful experiment (preparation, data collection/analysis, theory/calculations, etc.)
- Detailed - Provides a detailed description of most aspects of the experiment
- Adequate - Reasonable outline of experimental needs provided
- Insufficient - Too little detail to evaluate needs and/or predict successful completion
Expertise of Group (in both x-ray methods and science subject area)
- Extensive - Very experienced group with extensive history of successful outcomes
- Experienced - Group with proven track record of successes
- Gaining - Group has experience and demonstrated competence
- Novice - Group lacks experience or did not provide evidence of outcomes
Beam Time Request (BTR)
In order to submit a beam time request (BTR), you must have a valid project (an approved proposal). All projects are valid for two years following the proposal submission date. A BTR is a recap of your approved proposal. We ask that you review and update sample information, buffers, solutions, and equipment needs (this will be reviewed by safety).
Secondly, and as important, is the experimental plan section. In your proposal, your experimental plan may have discussed the 2-year plan but the BTR wants to explicitly know what are you planning to do this run.
To submit a beam time request log into the User Portal
- On the top menu select "My Beamtime Requests"
- To the left select "New Requests"
- Complete instructions can be found in the User Portal
Beam time Allocation and Scheduling
The total amount of beam time available on a beamline each cycle is a combination of the time required for commissioning, maintaining, and upgrading the beamlines and the time available for user experiments.
Each cycle, beamlines may designate a fraction of their time for specific technique experiments and schedulers allocate appropriate proposals for this purpose. All beamlines adhere to scheduling by proposal score, i.e. proposals which scored 1 - 1.75 are offered time first.
Beam Time Allocation and Scheduling
Once the deadline has passed for proposal and BTR submission scheduling begins in earnest by the Beamline Scientist and schedulers. Each beamline scientist is responsible for scheduling their beamline. Users are notified of scheduling confirmation through the User Portal and emails from CHESS User Office and/or Beamline Scientists.