Partikeldagarna, Göteborg 21 September 2007 LHC: Status and Plans Lyn Evans

L. Evans – EDMS document Schematic layout of the LHC

L. Evans – EDMS document Main parameters of LHC (p-p) Circumference26.7km Beam energy at collision7TeV Beam energy at injection0.45TeV Dipole field at 7 TeV8.33T Luminosity10 34 cm -2.s -1 Beam current0.56A Protons per bunch1.1x10 11 Number of bunches2808 Nominal bunch spacing24.95ns Normalized emittance3.75  m Total crossing angle300  rad Energy loss per turn6.7keV Critical synchrotron energy44.1eV Radiated power per beam3.8kW Stored energy per beam350 MJ Stored energy in magnets11GJ Operating temperature1.9K

L. Evans – EDMS document Descent of the last magnet, 26 April ’000 km underground at 2 km/h!

L. Evans – EDMS document Cross-section of LHC cryodipole

L. Evans – EDMS document Dipole magnetic flux plot

L. Evans – EDMS document Critical current density of technical superconductors

L. Evans – EDMS document Bending strength of dipoles

L. Evans – EDMS document Field errors in dipole production: b3

L. Evans – EDMS document Field orientation in dipoles

L. Evans – EDMS document Systematic field errors in dipoles

L. Evans – EDMS document Random field errors in dipoles

L. Evans – EDMS document Dipole-dipole interconnect

L. Evans – EDMS document Dipole-dipole interconnect: electrical splices

L. Evans – EDMS document DFBAO in Sector 7-8

L. Evans – EDMS document Magnet interconnections

L. Evans – EDMS document Specific heat of LHe and Cu

L. Evans – EDMS document Equivalent thermal conductivity of He II OFHC copper Helium II

L. Evans – EDMS document Phase diagram of Helium l line Saturated He II Pressurized He II

L. Evans – EDMS document Linear heat exchanger

L. Evans – EDMS document Sector 7-8 cooldown

L. Evans – EDMS document Courtesy F.Bordry

L. Evans – EDMS document Tracking between the three main circuits of sector 78 Courtesy F.Bordry 2ppm

L. Evans – EDMS document Arc plug-in module at warm temperature

L. Evans – EDMS document Arc plug-in module at working temperature

L. Evans – EDMS document Module with installation compression tooling

L. Evans – EDMS document RF bellows in the 1700 interconnections

L. Evans – EDMS document Transmitter prototype

L. Evans – EDMS document Transmitter prototype

L. Evans – EDMS document The electron cloud effect

L. Evans – EDMS document Simulated heat load as a function of SEY

L. Evans – EDMS document Energy stored in the accelerator beam, as a function of beam momentum. At less than 1% of nominal intensity LHC enters new territory. Stored energy density as a function of beam momentum. Transverse energy density is a measure of damage potential and is proportional to luminosity. Beam momentum & stored energy of colliders

L. Evans – EDMS document Transverse emittances from 3 different bunch intensities (72 bunches)

L. Evans – EDMS document Conclusions  The LHC design has integrated more than 30 years of accumulated knowledge of the behaviour of beams in hadron storage rings. The various correction systems will be adequate to stabilise the beams up to and beyond design luminosity.  The one new effect is the electron cloud which may be the limiting factor in pushing the luminosity well above the design value. This will depend on the efficiency of scrubbing that can be achieved.  The rate of increase in luminosity will be governed by our ability to protect the machine and detectors and of the detectors to cope with it.

L. Evans – EDMS document CERN accelerator complex

L. Evans – EDMS document Upgrade components

L. Evans – EDMS document Layout of the new injectors SPS PS2 SPL Linac4 PS

L. Evans – EDMS document Upgrade of LHC insertions  Intermediate ( ) upgrade of the two high- luminosity insertions using existing NbTi cable from dipole production. Seed money expected from Brussels but construction funds to be found.  Possible further upgrade to IE35 ( ) using advanced superconductor. Many ideas but luminosity lifetime will be a problem.