R807/808 or the Axial Field Spectrometer (AFS) was the major multipurpose experiment carried out at the ISR pp-collider.

A conventional C-type magnet with a 0.5 T field in the direction of the beams together with a 42-layer cylindrical drift chamber detector was used for momentum analysis over the full azimuth. A Cherenkov array provided particle identification up to 12 GeV/c transverse momentum. A fission-compensated Uranium-Scintillator hadron calorimeter was used for triggering and the energy measurement of charged and neutral hadrons over the full azimuthal range. Two arrays of NaI crystals were used for electron and photon studies. This was my Ph.D. experiment and I worked on the trigger system and the setting up of the Cherenkov detectors that were used to measure soft electrons.

I wrote a PhD thesis on the production of low PT positrons and low-mass electron-positron pairs which is available here.

Other publications

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The Intersecting Storage Rings

The Intersecting Storage Ring (ISR) was the worlds first high-energy hadron collider but as the name indicates it was not an accelerator since the particles were accelerated by the CERN Proton Synchrotron (PS). The protons (but also anti-protons, deuterium and alpha-particles) were brought from the PS to the ISR via two transfer tunnels to the two 940 m long storage rings in the ISR. The hadrons could be brought into collision at 8 intersection points around the rings. The maximum collision energy obtained was 63 GeV and this was a considerably higher value than at previous fixed-target machines. Unfortunately the discovery potenial of this unique machine was not used due to small low-budget experiments which did not cover a large enough solid angle and it was not until the end of its lifetime that large experiments such as the AFS were carried out.

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