“This new achievement augurs well for the next LHC run starting in 2015,” said CERN’s Director for Accelerators and Technology, Steve Myers, “High intensity beams are vital for the success of the LHC programme. More intense beams mean more collisions and a better chance of observing rare phenomena.”
To put this into context, of the 6 million billion proton-proton collisions generated by the LHC, the ATLAS and CMS experiments have each recorded around 5 billion collisions of interest over the last three years. Of these, only around 400 produced results compatible with the Higgs-like particle whose discovery was announced in July.
A beam in the LHC is not a continuous string of particles, but is divided into hundreds of bunches, each a few tens of centimetres long. Each bunch contains more than a hundred billion protons. During the last few days, the space between bunches has been successfully halved, achieving the design specification of 25 nanoseconds rather than the 50 nanoseconds used so far. Halving the bunch spacing allows the number of bunches in the beam to be doubled. A record number of 2748 bunches was recorded in each beam last weekend, almost twice as many as the maximum reached previously in 2012, but at the injection energy of 450 GeV and without collisions. Several hours of physics were then performed with up to 396 bunches in each beam, spaced by 25 nanoseconds, each beam being accelerated to the energy of 4 TeV.
“The LHC’s performance has exceeded all expectations over the last three years,” said Steve Myers, “The accelerator delivered more than 6 million billion collisions and the luminosity has continuously increased. It’s a fantastic achievement, and I’m incredibly proud of my team.”
The luminosity, a crucial parameter measuring the rate of collisions of an accelerator, has reached a value of 7.7x1033cm-2s-1, more than twice the maximum value obtained in 2011 (3.5x1033cm-2s-1). The collision energy was increased from 7 TeV in 2011 to 8 TeV in 2012.
This year-on-year improvement in performance has allowed the LHC experiments to obtain important results quicker than expected. In addition to the spectacular discovery of a Higgs-like particle announced in July, the experiments have led to many other studies improving our understanding of fundamental matter.
At the beginning of 2013, the LHC will collide protons with lead ions before going into a long maintenance stop until the end of 2014. Running will resume in 2015 with increased collision energy of 13 TeV and another increase in luminosity.
1. CERN, the European Organization for Nuclear Research, is the world's leading laboratory for particle physics. It has its headquarters in Geneva. At present, its member states are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a candidate for accession. Cyprus, Israel and Serbia are associate members in the pre-stage to membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have observer status.
Press office | Newswise
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine