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LHC sets world record beam intensity

Geneva, 22 April 2011. Around midnight this night CERN's Large Hadron Collider set a new world record for beam intensity at a hadron collider when it collided beams with a luminosity of 4.67 x 1032cm-2s-1. This exceeds the previous world record of 4.024 x 1032cm-2s-1, which was set by the US Fermi National Accelerator Laboratory's Tevatron collider in 2010, and marks an important milestone in LHC commissioning.
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Title: Dark matter searches at LHC
Authors: Vasiliki A. Mitsou (Valencia U., IFIC)

Besides Standard Model measurements and other Beyond Standard Model studies, the ATLAS and CMS experiments at the LHC will search for Supersymmetry, one of the most attractive explanation for dark matter. The SUSY discovery potential with early data is presented here together with some first results obtained with 2010 collision data at 7 TeV. Emphasis is placed on measurements and parameter determination that can be performed to disentangle the possible SUSY models and SUSY look-alike and the interpretation of a possible positive supersymmetric signal as an explanation of dark matter.

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Syracuse University physicists first to observe rare particles produced at the Large Hadron Collider at CERN

Shortly after experiments on the Large Hadron Collider (LHC) at the CERN laboratory near Geneva, Switzerland, began yielding scientific data last fall, a group of scientists led by a Syracuse University physicist became the first to observe the decays of a rare particle that was present right after the Big Bang. By studying this particle, scientists hope to solve the mystery of why the universe evolved with more matter than antimatter.
Led by Sheldon Stone, a physicist in SU's College of Arts and Sciences, the scientists observed the decay of a special type of B meson, which is created when protons travelling at nearly the speed of light smash into each other. The work is part of two studies published in the March 28 issue of Physics Letters B. Stone leads SU's high-energy physics group, which is part of a larger group of scientists (the LHCb collaboration) that run an experiment at CERN. The National Science Foundation (NSF) funds Stone's research group.

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LHC Report: A new luminosity record

After about one month of operation, the LHC has already accumulated an integrated luminosity of 28 pb-1, which corresponds to over 50% of the total delivered to the experiments in 2010. This impressive start to the LHC run in 2011 bodes well for the rest of year.

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LHC Could Be the First Time Machine

One of the major goals of the collider is to find the elusive Higgs boson: the particle that physicists invoke to explain why particles like protons, neutrons and electrons have mass. If the collider succeeds in producing the Higgs boson, some scientists predict that it will create a second particle, called the Higgs singlet, at the same time.
According to Weiler and Ho's theory, these singlets should have the ability to jump into an extra, fifth dimension where they can move either forward or backward in time and reappear in the future or past.

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Title: Causality-Violating Higgs Singlets at the LHC
Authors: Chiu Man Ho, Thomas J. Weiler

We construct a simple class of compactified five-dimensional metrics which admits closed timelike curves (CTCs), and derive the resulting CTCs as analytic solutions to the geodesic equations of motion. The associated Einstein tensor satisfies the null, weak, strong and dominant energy conditions; in particular, no negative-energy "tachyonic" matter is required. In extra-dimensional models where gauge charges are bound to our brane, it is the KK modes of gauge-singlets that may travel through the CTCs. From our brane point of view, many of these KK modes would appear to travel backward in time. We give a simple model in which such time-travelling Higgs singlets can be produced by the LHC, either from decay of the Standard Model Higgses or through mixing with the SM Higgses. The signature of these time-travelling singlets is a secondary decay vertex pre-appearing before the primary vertex which produced them. The two vertices are correlated by momentum conservation.

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LHC 'has two years to find Higgs'
Researchers working at the Large Hadron Collider have said they expect to discover the Higgs boson particle by the end of 2012.
If the LHC does not turn up evidence of the Higgs during this run, physicists say they may have to significantly alter their views of physical laws.

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Hunt for dark matter closes in at Large Hadron Collider

Physicists are closer than ever to finding the source of the Universe's mysterious dark matter, following a better than expected year of research at the Compact Muon Solenoid (CMS) particle detector, part of the Large Hadron Collider (LHC) at CERN in Geneva.
The scientists have now carried out the first full run of experiments that smash protons together at almost the speed of light. When these sub-atomic particles collide at the heart of the CMS detector, the resultant energies and densities are similar to those that were present in the first instants of the Universe, immediately after the Big Bang some 13.7 billion years ago. The unique conditions created by these collisions can lead to the production of new particles that would have existed in those early instants and have since disappeared.
The researchers say they are well on their way to being able to either confirm or rule out one of the primary theories that could solve many of the outstanding questions of particle physics, known as Supersymmetry (SUSY). Many hope it could be a valid extension for the Standard Model of particle physics, which describes the interactions of known subatomic particles with astonishing precision but fails to incorporate general relativity, dark matter and dark energy.

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Particle Pings: Sounds Of The Large Hadron Collider

Deep beneath the border of France and Switzerland, the world's most massive physics machine is sending subatomic particles smashing into each other at speeds nearing the speed of light. Physicists working with the 17-mile-long Large Hadron Collider hope it will help solve some of the universe's mysteries.
But first, researchers must overcome two very mundane hurdles: how to handle all of the data the LHC generates, and how to get non-scientists to care.
One physicist has a novel way to solve both problems: sound.

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First heavy-ion collisions in CMS - 3D view.
Animation by Loic Quertenmont.

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First CMS ZZ -> 4µ event.

We present event display and event kinematic details for the first ZZ -> 4µ event observed in CMS
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