A search for the Standard Model Higgs boson in proton-proton collisions with the ATLAS detector at the LHC is presented. In the datasets collected at √s = 7 TeV in 2011 and at √s = 8 TeV in 2012 the decay channels H→ZZ(∗)→4ℓ, H→γγ a H→WW(∗)→eνμν have been investigated. Clear evidence for the production of a neutral boson with a measured mass of 126.0 ± 0.4 (stat) ± 0.4 (sys) GeV is presented. This observation, which has a significance of 5.9 standard deviations, is...
An international team of researchers headed by young Oxford physicist Sam Vinko created a unique state of matter by isochorically heating a thin aluminium foil using a tightly focused X-ray beam produced by the LCLS (Linac Coherent Light Source) free-electron laser in California. Solid-density plasmas at a temperature > 106 K were produced under these irradiation conditions. By using the LCLS pulse, the authors have been able to study extremely well-defined hot...
The article describes a new measurement of the inelastic proton-air cross-section at a center-of-mass energy 57 TeV per nucleon. The cross-section is one of the basic quantities which characterize the nature of a two-particle collision. Its dependence on energy is connected to collision dynamics and the evolution of this dependence is sensitive to changes in the underlying collision mechanisms. The measurement of cross-section in interactions of cosmic ray protons with...
In order to investigate properties of matter at the smallest distances, we need to initiate, according to Heisenberg principle of uncertainty, processes with the largest possible changes in momentum. Before LHC, the best place to study such processes was collider Tevatron in Fermilab. There, the protons were collided with antiprotons at center of mass energy of √s=1.96 TeV, which was at that time the largest energy available at laboratory.Protons interact with...
Laser driven ion acceleration is a very promising approach which might drastically reduce the typical size and cost of standard acceleration systems. Nevertheless the laser accelerated beams have to be improved in terms of energy, current, divergence, shot-to-shot stability, etc. In a recent experimental campaign our team has greatly improved both the maximum energy (about 60%) and number (approximately 5 times) of the proton source by using a high intensity laser and...
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