The Construction of ATLAS and CMS Della Negra, Michel; Jenni, Peter; Virdee, Tejinder S
Annual review of nuclear and particle science,
10/2018, Letnik:
68, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The article describes the early years of the two large general-purpose experiments, ATLAS and CMS, at CERN's Large Hadron Collider (LHC). It covers the early conception of the detector designs to ...achieve the physics goals, the subsequent building of the worldwide collaborations, the evolution of the designs incorporating advances in technology and other considerations, and the painstaking global construction efforts. A detailed technical description of the detectors is beyond the scope of this review. This article also describes the development and deployment of the software and computing systems, by both the collaborations and the LHC Worldwide Computing Grid, in order to extract the physics results.
The journey in search for the Higgs boson started in earnest with the discovery of the W and Z bosons. The LHC accelerator, the ATLAS and CMS experiments were conceived in the late 1980s and early ...1990s, and it took two decades to turn the concepts to reality. Novel and innovative technologies needed to be developed and turned into superbly functioning engines for providing proton‐proton collisions in the case of the LHC and physics results in the case of the experiments. The most significant discovery so far to emerge from the LHC project is that of a heavy scalar boson, announced on 4th July 2012. The data collected so far point strongly to its properties as those expected for the Higgs boson associated with the Brout‐Englert‐Higgs mechanism.
The discovery of the Higgs boson in July 2012 by the ATLAS and CMS experiments at the Large Hadron Collider at CERN in Geneva is one of the great scientific achievements of this new century. The mechanism that led to the postulation of this elusive subatomic particle, some 50 years ago, imparts mass to the fundamental building blocks of nature.The discovery of the Higgs boson represents the coronation of the Standard Model (SM) of particle physics, a theory that describes our visible universe in exquisite detail. The clearest observed signal for the Higgs boson was found in its decay modes to two photons or into two Z bosons, that each in turn decay into electron‐positron or positive and negative muon pairs.
Detectors at LHC Virdee, Tejinder S.
Physics reports,
12/2004, Letnik:
403-404
Journal Article
Recenzirano
The 50th anniversary of the creation of CERN falls during the construction of its most ambitious project. The construction of the LHC, machine and experiments, is advancing well and proton–proton ...collisions are expected to take place in the summer of 2007. This paper outlines the challenges posed by the operation at a high-luminosity hadron collider, the design of the experiments, the R&D and prototyping that was required to select the detector technologies to face the challenges, the anticipated performance of the experiments, and the state of their construction.
Further tests of lead tungstate crystal matrices made in high-energy electron beams in 1996, using new crystals, new APDs and an improved test setup confirm that an energy resolution of better than ...0.6% at 100
GeV can be obtained when the longitudinal uniformity of the struck crystal is adequate. Light loss measurements under low dose irradiation are reported. It is shown that there is no loss of energy resolution after irradiation and it is demonstrated that the calibration change due to light loss can be tracked with a precision monitoring system. Successful tests with a preshower device, equipped with a silicon strip detector readout, are also described.