Beamline Attributes
| Maximum resolution | 0.66 Å @ 24.0 keV 0.93 Å @ 17.0 keV 1.3 Å @ 12.7 keV 2.7 Å @ 6.0 keV |
| Typical exposure time | 2 ms / frame (rotation method) |
New features at BioMAX
- Some of the old OTP tokens for remote access set up in 2023 have a one year expiration time. If the token has expired you will get an error when trying to connect to MAX IV: “Bad username or password. Please reenter information from your token card“. If you get such a message and are sure you entered the correct OTP, please follow the instructions to set up a one time password application. We recommend testing that the OTP generator is set up properly before remote beamtime by connecting to the offline HPC cluster. See Remote Experiments at BioMAX.
- New MXCuBE features (September 2024):
- The default energy for data collection in MXCuBE is 17 keV. A
- A new beam focus size of 20×20 microns can be selected, which provides a better flux for data collection from crystals of this size. The 20 micron beam shaping aperture is inserted automatically when selecting this focus size.
- The default exposure time for rotation data collection is 2 ms. This speed is supported by the new detector installed in 2024 and it results in slightly better data quality. With 2 ms, the beam transmission can be increased to 50-100 %, depending on the absorbed dose. Note that for mesh scans and characterization data collection a slower exposure time (10 ms or larger); in these cases, the minimum exposure time is limited by the speed of the diffractometer motors.
- The HPC clusters are being upgraded from CentOS to Rocky Linux. This should not make any noticeable difference in performance. At the same time, the Thinlinc HPC front end desktop has a new look and feel. See the virtual tour. The online cluster front end clu0-fe-1 has been deprecated. Use instead clu0-fe-2 or clu0-fe-3. The offline cluster front end is still offline-fe1.
- Automated data collection is available upon request before the beamtime. Please read Automated data collection to determine if it is suitable for your experiment.
- On week 12 2024 we replaced the detector with an Eiger2 XE CdTe 16M. Note: If you reprocess the data manually beware that XDS based pipelines incorrectly treat the CdTe sensor as silicon by default. The exception is autoPROC version 20240123 and we recommend you upgrade to this version. In other cases you need to replace or add the SILICON keyword in your XDS.INP file with the value present in the MAX IV XDS.INP generated by the autoprocessing; this file can be found in the biomax data disk under ‘proposal’/’date’/process/’protein’/’sampleid’/xds_sampleid’. You can use the same value for different data sets as long as the X-ray wavelength is the same.
Getting beamtime at BioMAX
The first step to gain access to BioMAX is to submit a proposal for beamtime. Normal and BAG proposals can be submitted during the call for proposals period. Fast Access proposals are accepted at any time. For proprietary proposals for industry, please contact the Industrial Relations Office. For Training and Education, please contact beamline staff. See also MAX IV access modes.
Preparing for beamtime
The MX groups holds periodical user training workshops. New users are encouraged to apply for one of these training sessions in advance of their first beamtime. The workshops are announced some weeks in advance.
- Once the user office has notified you about approval of your proposal, BioMAX staff will contact you about suitable times to schedule your beamtime. You will also need to sign an Agreement for Access to MAX IV Laboratory. Please read more about the applicable policies here.
- Before your experiment please use the DUO interface to apply for an access card (unless you plan a remote experiment) and complete the safety quiz. You also use DUO to define an experiment session and declare the shifts it will comprise, the number of participants in the experiments and the samples used. Samples need to be declared two weeks in advance, except non-hazardous samples, which can be declared up to three days before the experiment. In addition, creating the experimental session is required for obtaining remote access to data collection.
- Prepare the samples. The sample exchanger at MAX IV supports SPINE mounts of standard length (cap + pin + loop = 22 mm) mounted in Universal Pucks (UniPucks) only. It is critical that the samples are the correct length, as longer samples can cause the sample changer to collide with the diffractometer. There are UniPucks available at the beamline in case you do not have any. Please contact staff if you need to borrow the UniPucks. The sample transfer can be done onsite.
- If you need to do extensive sample preparation on-site (beyond cryo-cooling or quick soaks) you will need to arrange in advance training to use the Biological lab.
- After a session has been created in DUO, use EXI (EXtended IsPyB) to arrange sample shipment. This step is compulsory for automated sample mounting with the sample exchanger, even if you are planning to transport the dewar yourself. If you ship the samples, please enclose the labels generated by EXI, together with the waybill for the return shipment and, if relevant, the customs declaration.
Carrying out the experiment
Note: The starting time for morning experiments is 09:00 (CET), 13:00 for afternoon experiments, and between 17:00 and 17:30 for evening experiments. The experiment starting times differ from the official DUO shifts to allow staff to conduct a thorough daily beamline preparation and sample loading between 8:00 and 9:00.
MXCuBE3 is the standard software to collect data at BioMAX. As soon as the data are collected, the software launches several different pipelines to process the data. The results can be accessed any time via EXI. We also provide computing facilities for manual reprocessing of the data. Please remember to acknowledge in your publications any tools used at BioMAX to collect and process the data.
All academic users can use all the software installed on MAX IV computers to process data. However, we may not have appropriate licences for industrial users. If in doubt, please consult with staff.
Data transfer
Currently, users belonging to an institution with a valid license can use Globus for data transfer. We also provide an sftp server for remote data transfer. To prevent malware infections, we do not allow the use of external disks.
After the experiment
Please use the DUO interface to provide feedback about your experiment and report any publications arising from it. Submission of an experimental report is very important for renewal of proposals. Do not forget to acknowledge MAX IV and other instruments and software used during the experiment. Raw data sets archived at MAX IV can be referenced via a unique identifier number. Log in to SciCat to locate the PID assigned to your data. Once the proposal PI makes the data public, everyone will be able to download the data.