Neutron tomography data of high-purity metal rods using golden-ratio angular acquisition (IMAT, ISIS)

General description:

This is a neutron tomography projection data set acquired at the IMAT beamline of the ISIS Neutron and Muon Source, Harwell, UK. It was acquired using a 512-by-512 pixel MCP time-of-flight detector (pixel size 0.055 mm) binned into 2332 energy intervals between 1.7Å and 5.5Å using a parallel-beam scan geometry. 186 projections, each with 30 min exposure time (20 micro A), in the golden-ratio angular acquisition-mode. That is, a constant angular increment of (sqrt(5)-1)/2*180 degrees = 111.2461 degrees was used, and if an angle was outside 0 to 180 it was wrapped to that interval. Data was preprocessed to compensate for distortions caused by detector electronics and then summed over energy bins to simulate a white-beam data set. The data has not been corrected for centre-of-rotation offset. This can be achieved for example by cropping 52 pixels off all images from the left.

The sample was an Al cylinder (Ø 22mm) with cylindrical inset holes drilled from the top: A central 10mm hole (left empty) and 5 holes of 3mm in pentagon corner positions and 5 holes of 1mm in pentagon corner positions offset from the 3mm set. High-purity elemental Cu, Fe, Ni, Ti, and Zn were inserted in the 3mm and 1mm holes with a single 1mm hole left empty.

File descriptions:

The data consists of a single ZIP file with the following contents:

• 186 TIFF files - these are the individual projection images.
• golden_ratio_angles.txt - this text file lists the 186 angles in degrees at which the projections were acquired.
• scan_parameters.txt - this text file contains geometric metadata about the experimental scan configuration.