The Large Hadron Collider 2008–2013

Abstract

The Large Hadron Collider (LHC) was first suggested (in a documented way) in 1983 (S. Myers and W. Schnell, Preliminary performance estimates for a LEP proton collider, LEP Note 440, April 1983) as a possible future hadron collider to be installed in the 27 km "LEP" tunnel. More than 30 years later the collider has been operated successfully with beam for three years with spectacular performance and has discovered the longsought-after Higgs boson. The LHC is the world's largest and most energetic particle collider. It took many years to plan and build this large complex machine which promises exciting, new physics results for many years to come.I describe the LHC design objectives, review some of the more relevant beam effects, define the major accelerator components and parameters, and finally give an overview of the commissioning and operational performance since the initial turn on of the collider. The latter will include the major accident which took place in September 2008 and the subsequent repair and redesign of the faulty components.The first attempt to circulate beam in the LHC in September 2008 were initially very successful. However, after only nine days of preliminary beam commissioning, on 19 September 2008, disaster struck: the last octant was being ramped up in preparation for high energy operation when a magnet interconnect failed and the enormous energy stored in the superconducting magnets was released in an uncontrolled way and damaged around 600 m of the LHC installed equipment. The next 14 months were crucial for the machine. A crash programme for the repair of the damaged sector was initiated as well as in depth studies to understand the cause of the failure and make design changes which would ensure that such an accident could never reoccur in the future.In this paper, the story of the four years of the intensive activity since the accident is described starting with the repair of the damaged area and followed by the three very successful years of beam operation.

Demonstration of cooling by the Muon Ionization Cooling Experiment

“…The energy available in collisions between the constituent gluons and quarks in proton-proton collisions is considerably less than the energy of the proton beam because the colliding quarks and gluons each carry only a fraction of the proton's momentum. Muons carry the full energy of the beam, making muon colliders attractive for the study of particle physics beyond the energy reach of facilities such as the Large Hadron Collider 19 .…”

Reflectivity and photoelectron yield from copper in accelerators

“…Samples No. 5, 6 are potentially interesting materials that could be used for the construction of HL-LHC, HE-LHC and FCC-hh [2,12,15,16,[33][34][35]37,39,[47][48][49][50].…”

“…In particular we have analyzed: Copper LHC beam screen (BS), saw-tooth zone on the horizontal plane of the BS. It has been designed to be compliant with many functional requirements, one being the reduction of reflected photons reaching its top and bottom parts [31,33,34]. To this end a "saw-tooth" (ST) structure has been grooved into the 75 μm Cu-film during the co-lamination process.…”

“…During the LHC design and development, the SR, impedance and the e − cloud related heat load on the cold bore have been significantly reduced by the introduction of a beam screen (BS) at higher temperatures (T ≈ 20 K) inside the cold bore [33]. The BS has to be compliant with many other functional requirements [31].…”

Laser-driven electron beam and radiation sources for basic, medical and industrial sciences

“…To date high energy accelerators are based on high power RF technologies that accelerate charged particles with electric fields up to 100 MV/m at most, which is a limit stably produced in metallic, electromagnetic cavities due to electrical surface heating and breakdown. As illustrated with the Large Hadron Collider (LHC) 3 ) and the future linear collider 4 ) beyond the TeV energy range, the overall accelerator complex will range over several tens kilometer size and amount to enormous expenditure to be built. A remarkable scaling-down of high-energy accelerators may be simply brought through by using much higher accelerating fields than the present limits.…”