Its sad to hear of his passing. I met Roger first when he led the EMMA FFA project, built and successfully demonstrated at Daresbury lab. He was keen to promote accelerator physics projects in various applications such as cancer treatment, nuclear waste transmutation, particle physics etc

#ipac25

Nice explanation! I happen to use a CRT electron gun in a accelerator physics experiment.

Minor point - I think the steering was done with electrostatic fields not magnets

Nice to see some Lie operators!

So it turns out the integers in the array were declared as 16-bit using the function SELECTED_INT_KIND whereas when split in two steps it was converted into 32-bit

Ah...I think you cracked it. It's failing at 2^8. Thanks!

This is an example of how it occurs in the wild. (p,i,j) are the array indices

The good old ZX Spectrum with its rubber keyboard!

This is another I found on my lunchtime walk