BL4-2 Biological Small Angle Scattering/Diffraction

Planning and Running a Successful B-SAXS/D Experiment on BL 4-2

This page outlines what is required to receive beam time roughly in the order of occurrence. Please feel free to contact BL4-2 staff for questions, either scientific or technical.  Please also review SSRL general user proposal submission information.

1. Proposal Submission

The first step you need to complete for getting beam time at SSRL BL4-2 is to submit an experimental proposal which will be reviewed by the SSRL proposal panel. There are different types of proposals:

Standard Proposal

The Standard proposal are typically 3-5 pages of text describing the scientific background, the scientific merit of the proposed experiment as well as giving an experimental plan justifying the required beam time. Your proposal will be reviewed by an external review panel and receive a score based on scientific merit and feasibility which sets priority of receiving beam time among all competing proposals. However, receiving a reasonably high score does not guarantee a beam time slot due to oversubscription and other scheduling requirements. Structural Biology projects receive priority over non-biological studies on obtaining beam time on BL 4-2. There are three proposal deadlines per year:

           May 1, August 1, and November 1.

To submit a new proposal, please register at the SSRL User Portal and follow instructions there. After your proposal has been rated you will be notified to request beam time for the next run cycle (see step 2 below). A detailed step by step description of the proposal submission process can be found here.

Bio-SAXS/D Rapid Access Proposal

At least 1 block of 2-3 shifts will be set aside each month for Bio-SAXS/D Rapid Access proposals (during normal user operation runs). The proposals will be peer reviewed by the PRP SMB sub-panel for feasibility and scientific merit. If beamtime is available, the spokespersons will be contacted to arrange for beam time typically within 2-8 weeks after submission. Same as for the standard proposal, the score received by the proposal will set the priority of scheduling among the available slots. The BioSAXS Rapid Access proposals have no deadlines associated with them and can be submitted any time through the SSRL User Portal. A detailed step by step description of the proposal submission process can be found here.

Letters of Intent (LOIs)

There is a way of getting a short beam time without going through the full review process. More information about this can be found in the SSRL User Portal or by contacting BL4-2 staff.

2. Beam Time Request

SSRL operates as a dedicated synchrotron radiation source for typically 9 months per year (usually from November through July). The SSRL administration schedules your beam time slot for standard proposals on average 3 times a year according to user request and proposal rating. Beam Time Request Forms are sent to the Spokesperson for all active proposals approximately three months in advance of each scheduling period. Please include the specifics of your experimental setup with the beam time request. Note that in order to schedule your allocated beam time into a time slot with the appropriate experimental setup, it is necessary that you give us as much information about your experimental setup requirements as possible. For further information or advice, please contact the BL4-2 staff prior to sending in beam time requests.

3. Accept Time and Submit Support Request

Once your beam slot has been scheduled, please log in to the SSRL User Portal and accept the allocated slot. At this point you should also fill in the experimental Support Request form. In the form you can verify available equipment during your beam time. Please update sample safety issues, if any. Additional support can also be requested, including special equipment and access to the SSRL sample preparation laboratory.

4. Computer Accounts

A computer usage security agreement must be on file prior to the beginning of the experiment.  Forms are included with beamtime assignments and can also be obtained from the SSRL user administration office in Bldg. 120. Wireless network connections for User PCs to the SLAC visitor network are also available. You will also need an account on the Linux machine that is used for data collection. The beam line staff can help you set up the Linux account once you are on site. Please make sure to resolve all computer account issues during weekdays when your beam time starts on Friday or over the weekend.

5. Data backup

During the experiment the data will be stored on our Linux file server, which is NFS-mounted to other Linux PCs for data collection and processing. We strongly encourage you to back up the data right after (or even during) your experiment as due to limited filespace we cannot guarantee that the data be kept for more than three months after your experiment finishes. Access to the file server is provided through our Windows 7 PC via Samba protocol. Users can connect an external USB or Firewire hard drive (not provided) to one of our PCs for retrieving data. You can also use secure ftp or ssh protocol to directly transfer the accumulated data to your home institution.

6. Safety Training and Check-in Procedures

Please ensure that all of your safety training is up to date and follow the SSRL check-in procedures. SSRL requires that at least one member of your group has No-bars training and GERT training, which must be updated every two years. Safety training must be completed by Friday if your beam time starts over the weekend or on a holiday. Please schedule safety training with SSRL user administration.

7. End of Run Summary Form

Users are strongly encouraged to submit an end of run summary form electronically at the end of your allocated beam time through the SSRL User Portal in order to give us feedback on how we are doing and what we can do to improve your user experience. We would also be happy to discuss any technical issues and suggestions for improvement during user beam time.

8. Publishing your data

Proper acknowledgement for the use of SSRL facilities and the SMB resources is requested so that we can continue to support your experiments. BL4-2 users should use the following acknowledgement statement in all publications related to work fully or partially undertaken at SSRL BL4-2:

“Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. The SSRL Structural Molecular Biology Program is supported by the DOE Office of Biological and Environmental Research, and by the National Institutes of Health, National Institute of General Medical Sciences (including P41GM103393) . The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of NIGMS or NIH.”

Please also see the additional guidelines on publishing your data on the SSRL website.

9. Reporting publications

Please report any new publication that is a result of or uses experimental data obtained at SSRL to the SSRL User Administration.