FAQs

This page contains a list of Frequently Asked Questions. If your question isn't answered here, feel free to submit it using the form above. Your name and email address are optional, but if you provide these details, beamline staff will respond to you directly.

Previous FAQs:

Q: How can I decide the camera length and the energy of X-ray for my experiments?

A: The measurable q-range is defined by the combination between the camera length and the X-ray energy (wavelength). Thus, these 2 parameters must be chosen carefuly depending on the period length, lattice size or molecular size of your sample. A useful guide can be found in the beamline manual and a new perspective has been included in dawn, DEDI where you can try various options for camera set up.

I22 staff can help and give some ideas for this question, please ask the I22 staff before making the beamtime application or your beamtime!

Q: The lab is out of a consumable item, such as gloves/wipes/tips. How do I get more?

A: During office hours, let the lab technician know. The lab technician extension is posted in the control room and the data reduction room (Zone 2 pod). Out of hours (after 6 PM, before 9 AM and on the weekends), please contact the EHCs on 8787 for assistance.

Q: What file format is my data? How do I analyse it?

A: We aim to provide data reduction and analysis instructions on this website. If you need any further guidance, please ask your local contact. Presently, I22 data is saved in the Nexus format (.nxs), but legacy files in the BSL format are also generated on users demand from each scan or set of frames, so if you have older or custom software that is designed to analyze BSL files, these will still work. Please, advise your local contact if you want to collect BSL files as well.

Q: I need help modifying a custom sample environment. Can Diamond staff assist me?

A: It depends on what you need. Please contact beamline staff if you intend to bring a custom sample environment, so we can begin to assist you as soon as possible. Our new Sample Environment Development Lab has been set up to make this process smoother. Often we help users with custom spacers or other adapter sections to make an existing sample environment match with the space envelope available on the beamline - if this is a concern for your experiment, please ask, as we may already have the necessary part from a previous setup! Our technicians have also assisted users with custom sample cells and other small designs on occasion. We do not do elaborate machining on site, however, and this assistance is limited to smaller tasks. We also require significant (at least four weeks) advance notice that you will need technical or shop assistance with your sample environment.

Q: What camera length and energy did my experiment use last time?

A: These parameters are crucial for your data analysis, so it's important to make a note. Usually, we have set up the requirements you have requested. The camera length is recorded in the SAXS and WAXS calibration files, which can be found in the 'processing' subfolder of your experimental folder. The energy record can be found in each raw data *.nxs file.

Q: In each dataset directory there are subdirectories with 5 files. What are they?

A: This is only true if you have asked for BSL files. Our Nexus files include a .nxs header and a variable number of .h5 files, the first two for SAXS and WAXS data, two more include the necessary I0 and Beamstop Diode data, others are included as necessary. These are storted in HDF5 format. In the dataset directory, the files are stored in BSL format that provides 5 files following this filename format.

*0.* file is the header file containing information on the sample, the number of frame you have collected etc… It is an ASCII file
*1.* file is the file containing the intensity of the SAXS data
*2.* file contains the normalisation channel. By default, it is number 2 on I22.
*3.* file contains the WAXS data
*4.* contains some other information about the detector but it is used for debugging.
The last 4 files are binary files.