Absorbers for the high luminosity insertions of the LHC

Conference · Mon Jun 01 04:00:00 EDT 1998

OSTI ID:666052

Turner, W C; Hoyer, E H ^[1]; Mokhov, N V ^[2]

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1. Lawrence Berkeley National Lab., CA (United States)
2. Fermi National Accelerator Lab., Batavia, IL (United States)

At design luminosity and inelastic cross section {sigma}{sub pp} = 80mb there are 8 {times} 10{sup 8} inelastic collisions per second at the high luminosity interaction points IP1 and IP5 of the LHC. These interactions give rise to {approximately} 0.9 kW of power in collision products leaving an IP in each direction. The inelastic collision power carried off by neutrals, mostly neutrons and photons, in each direction and intercepted by neutral absorbers (TAN) has been estimated with the MARS13 code to be 210W. Similarly the collision power escaping the beam tube and incident on the front face of the inner triplet quadrupole absorber (TAS) has been estimated to be {approximately} 270W, mostly carried by charged pions and photons. Special purpose absorbers must intercept this power to prevent quenching the inner triplet quadrupoles (Q1 to Q3) and the twin aperture magnets outside the second beam separation dipole D2. Because of the high incident flux of collision products near zero degrees the absorbers are natural places to consider for the location of radiation hard gas ionization detectors which could be used for: (1) measurement of luminosity, (2) measurement of the beam transverse dimensions at the IP and (3) feedback control of the colliding beam centers at the IP`s to maximize luminosity. The following sections describe: (1) the conceptual design of the absorbers, (2) the radiation deposition and activation calculations and (3) the possibilities for instrumentation.

• Research Organization: Lawrence Berkeley National Lab., Accelerator and Fusion Research Div., Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Research, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 666052
• Report Number(s): LBNL--41964; CBP-Note--256; CONF-980671--; ON: DE98059377
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM LUMINOSITY
BEAM MONITORS
CERN LHC
CONTROL SYSTEMS
DESIGN
EQUIPMENT PROTECTION DEVICES
POSITIONING
QUADRUPOLES