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Satellite bunch Collection of particles inside RF buckets that do not correspond to nominal bunch positions. The nominal bunch spacing for the LHC is 25 ns while the separation of RF buckets is 2.5 ns. In other words, there are 9 RF buckets between two nominal LHC bunch positions that should be empty.
Sector The part of a ring between two successive insertion points (IP) is called a sector. Sector 1-2 is situated between IP1 and IP2.
Separation / recombination magnets Special dipole magnets left and right from the triplet magnets that generate the beam crossings in the experimental insertions
Short Straight Section (SSS) Assembly of the arc quadrupole and the lattice corrector magnets. Each SSS consists of one quadrupole magnet, one Beam Position Monitor (BPM), one orbit corrector dipole (horizontal deflection for focusing and vertical deflection for defocusing quadrupoles), one lattice correction element (i.e. trim or skew quadrupole elements or octupole magnets) and one lattice sextupole or skew sextupole magnet.
SPecial Straight Section (SPSS) Quadrupole assemblies of the insertion regions. The SPSS features no lattice corrector and sextupole magnets and has only orbit correction dipole magnets and BPMs.
Spool piece correction magnets Correction magnets directly attached to the main dipole magnets. The spool piece correction magnets are included in the dipole cryostat assembly.
Strand A superconducting strand is a composite wire containing several thousands of superconducting filaments dispersed in a matrix with suitably small electrical resistivity properties. The LHC strands have NbTi as superconducting material and copper as resistive matrix.
Superconducting cable Superconducting cables are formed from several superconducting strands in parallel, geometrically arranged in the cabling process to achieve well controlled cable geometry and dimensions, while limiting the strand deformation in the process. Cabling several strands in parallel results in an increase of the current carrying capability and a decrease of the inductance of the magnet, easing protection. The LHC cables are flat, keystoned cables of the so-called Rutherford type.
Super pacman bunches Bunches that do not collide head-on with a bunch of the other beam in one of experimental IPs.

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