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<2> photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

In copper.

This is a collision region from the world’s first proton collider, the Intersecting Storage Rings. The ISR was used at CERN from 1971-84 to study proton-proton collisions at the highest energy then available (60GeV). When operational, ISR collision regions were surrounded by detectors as shown in the photo. In 1972, the surprising discovery of fragments flying out sideways from head-on proton-proton collisions was the first evidence of quark-quark scattering inside the colliding protons . This was similar to Rutherford’s observation in 1911 of alpha particles scattering off the tiny nucleus inside atoms of gold. The ISR beamtubes had to be as empty as outer space, a vacuum 100 000 times better than other CERN machines at the time.

Prototype of Linac 2, a Linear proton accelerator used in the PS (proton synchrotron accelerator injection system). A Linearaccelerator is a particle accelerator which accelerates charged particles - electrons, protons or heavy ions - in a straight line. Charged particles enter at one end and are accelerated towards the first drift tube by an electric field. Once inside the drift tube, they are shielded from the field and drift through at a constant velocity. When they arrive at the next gap, the field accelerates them again until they reach the next drift tube. This continues, with the particles picking up more and more energy in each gap, until they shoot out of the accelerator at the other end. Linac 2,also called Alvarez Proton Linac, was first run in 1978 and is still running today. It provides pulsed (1 Hz) beams of up to 170 mA at 50 MeV with pulse lengths varying between 20 and 150 ms depending on the number of protons required.

Emulator 370/E used to analyse data from the UA1 detector.

prototype of the endcap of CMS (compact muon solenoid), a detector for the LHC.

Three pieces. Wire chambers used for the beams at CERN's Proton Synchrotron accelerator in the 1970s. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Magnetoscriptive readout wire chamber.Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

This object was a prototype for a wire chamber with a cylindrical symetry. It was never used in an experiment.

wire chamber or spark chamber?