Collider detectors for multi-TeV particles

Collider detectors for multi-TeV particles are complex instruments that detect and measure simultaneously the parameters of thousands of particles in a detector volume of 10,000--20,000~m$^3$. This splash of particles is produced in ultra-energetic collisions between two protons in counter-rotating beams in a particle collider. The next generation of these instruments, at present under construction, aims at the study of physics phenomena at energies of $10^{11}$--$10^{12}$~eV or more, such as the mechanism generating the masses of fundamental particles, the concept unifying the fundamental forces or the process through which the matter--antimatter symmetry was violated during the first microsecond after the Big Bang. These instruments are composed of several layers of detectors, each with a specific measurement task, and are subdivided into $\sim 10^8$ detection cells. Collisions exhibiting novel physics signals are expected to occur only very rarely, typically at the rate of one in $10^{10}$ collisions or less; therefore, these instruments also push the data rates to limits exceeding $10^{15}$ bits/s. Worldwide collaborations of thousands of physicists and engineers are building these research facilities in concert with industry.