From Cern Courier: “TOTEM construction complete” 

“TOTEM is designed to make precise measurements of the total proton–proton cross-section and to perform detailed studies of elastic and diffractive proton–proton scattering. It requires dedicated runs of the LHC at low luminosities to allow the movable Roman Pots to bring detectors as close to the beam as possible.

TOTEM Installation platform

The TOTEM experiment studies forward particles to focus on physics that is not accessible to the general-purpose experiments. Among a range of studies, it will measure, in effect, the size of the proton and also monitor accurately the LHC’s luminosity.

To do this TOTEM must be able to detect particles produced very close to the LHC beams. It will include detectors housed in specially designed vacuum chambers called ‘Roman pots’, which are connected to the beam pipes in the LHC. Eight Roman pots will be placed in pairs at four locations near the collision point of the CMS experiment.

Although the two experiments are scientifically independent, TOTEM will complement the results obtained by the CMS detector and by the other LHC experiments overall.

The TOTEM experiment involves 50 scientists from 10 institutes in 8 countries (2006).