Data from CoSAXS is stored centrally at MAX IV and is available for further processing using MAX IV resources – or for download using either the Globus connect service or sftp. Detailed information about downloading the data can be found here: Data access

It is possible to access MAX IV computing resources by setting up a VPN connection to MAX IV. Instructions can be found here: VPN connection to MAX IV

File location and structure:

All scans at CoSAXS result in a number of files written in the HDF5 format (*.h5). The files are written to be NeXuS compatible.

The raw files are stored in /data/visitors/cosaxs/#Proposal/#Visit/raw/ while reduced files are stored in /data/visitors/cosaxs/#Proposal/#Visit/process/. 

Each scan will be saved with the name scan-####.h5 where #### is a sequential number. It is important to keep track of this number and the corresponding sample/experiment, e.g. by using the elogy logbook (https://elogy.maxiv.lu.se). The scan-####.h5 file is a master file that contains the command issued to perform the scan, the scanned parameters (e.g. motor positions), experimental channels (e.g. beam intensity, position, temperature) a snapshot of the instrument at the beginning of the scan and links to the detector datafiles. The data from the detectors are located in separate files, e.g. scan-####_eiger.h5 and scan-####_pilatus.h5. The link from the master file to the detector data is relative, and thus all files must be located in the same folder.

To visualize the data and the file structure we recommend to use silx view (http://www.silx.org/doc/silx/latest/install.html) which is available on the control computers. As the area detector data is compressed using a bit-shuffle algorithm, it is necessary to install hdf5plugin (https://pypi.org/project/hdf5plugin/).

Page manager: Ann Terry January 31, 2023