학술논문

Correcting the LHC /spl beta/* at collision
Document Type
Conference
Source
Proceedings of the 2003 Particle Accelerator Conference Particle accelerator conference Particle Accelerator Conference, 2003. PAC 2003. Proceedings of the. 4:2237-2239 vol.4 2003
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Nuclear Engineering
Robotics and Control Systems
Large Hadron Collider
Lattices
Error correction
Magnets
Optical tuning
Testing
Colliding beam devices
Language
ISSN
1063-3928
Abstract
To correct the /spl beta/* at the main collision points (IP1 and IP5) simultaneously for the two counterrotating proton beams in the Large Hadron Collider (LHC), a set of specific quadrupoles in the noncommon part of the machine is used. Due to the antisymmetric optics, several quadrupoles on each side of the insertion have to be employed. The change of /spl beta/* is accomplished by incrementing the quadrupole gradients. This set of increments is referred to as /spl beta/* tuning knob. The increments were calculated by rematching /spl beta/* in a range of /spl plusmn/20 % about the nominal value. Linear curves were fitted to the variation of increments to construct a linear tuning knob. This was done for each plane using MAD 8 and repeated with MAD X. The linear behaviour and the orthogonality of the knobs were investigated for the LHC lattices V6.2 and V6.4. Different field errors were introduced in the lattice and the correction efficiency of the knobs was studied.