Techniques¶
What I-TOMCAT is designed to do, as intent. Modelling exercise.
A technique is a portable Catalog Method; a Practice is how a facility adapts it. The PSI Practices that bind these are carried pending on the PSI site page until PSI staff confirm them. The function view survives the eventual equipment choices, which is why it can be written from the public pages before the controls are wired.
I-TOMCAT is a hard X-ray tomographic-microscopy beamline. Its techniques are the tomography-family Methods the catalog already carries, the same ones the APS 2-BM pilot earned:
| Technique | Catalog Method | What it is for |
|---|---|---|
| Standard microtomography | tomography |
absorption-contrast 3D imaging on the U15 undulator, monochromatic 8-30 keV |
| Propagation-based phase contrast | tomography |
edge-enhanced imaging of weakly-absorbing samples (a propagation distance, not a separate fixture) |
| Fast / dynamic 4D tomography | streaming_tomography |
continuous high-speed acquisition via the GigaFRoST streaming camera, for in-situ dynamics |
A few points of intent shape the model:
- The GigaFRoST camera is the dynamic-tomography enabler. The PSI in-house continuous-streaming camera (up to 1255 fps full-frame, ~8 GB/s, up to ~33,875 Hz on a reduced ROI) is what distinguishes I-TOMCAT's fast and dynamic 4D tomography from a standard CT beamline. It maps to the catalog
streaming_tomographyMethod, not a new one. - Phase contrast is a propagation distance, not a separate station. Propagation-based phase-contrast imaging runs on the same endstation by moving the detector back from the sample; it is an acquisition mode over one set of optics, modelled under
tomography, mirroring the 2-BM decision. - Grating interferometry is out of scope. The legacy TOMCAT offered it only occasionally; it is not modelled here and is not one of the SLS Practices until staff confirm it is offered on the rebuilt beamline (TECH-1).
The concrete acquisition recipes (scan sequences, energies, exposure) are not written yet; they join if the deployment firms toward a real connection. See Open questions for what must be confirmed first.