New Neighbour for ATLAS Tilecal Prototypes

6th August 2015 – There's a new resident in ATLAS' Tile Hadronic Calorimeter (Tilecal) development laboratory: the last surviving UA2 central calorimeter module. After years at CERN's Microcosm exhibition, the module has found a new home next to prototype ATLAS Tilecals. Side-by-side, they illustrate the progress in sampling organic scintillator calorimeters over the past 35 years.

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ATLAS control room

A summer evening in the ATLAS control room

4th August 2015The sun has already set over Geneva when I finally walk out from the ATLAS control room. We have been waiting for beams to be injected into the machine since the early hours of the afternoon, but without much success so far. Just a regular day for the most ambitious particle accelerator mankind has ever built, but a pretty boring afternoon for our entire shift crew.

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ATLAS Overview Week in Marrakech in 2013

From ATLAS Around the World: Brief history of Morocco in ATLAS

31st July 2015In 1996, Morocco officially became a member of the ATLAS collaboration. The eagerly awaited day had finally arrived, and the first Arabic and African country signed a collaborative agreement with CERN to participate in the great scientific adventure of particle physics.

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Average ATLAS charged-particle multiplicity

Physics and Performance With 13 TeV Proton Collisions

30th July 2015 – After a shutdown of more than two years, Run 2 of the Large Hadron Collider (LHC) has restarted with proton–proton collisions at a centre-of-mass energy of 13 TeV. This new phase will allow the LHC experiments to explore nature and probe the physical laws governing it at scales never reached before.

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This new result at 13 TeV (red circle) is compared to previous results from ATLAS

Top quarks in Run 2 are spot on

27th July 2015With a precision of just under 14% − currently dominated by our ability to understand how many proton-proton collisions have occurred at ATLAS (i.e. luminosity) − this measurement is able to confirm that quantum chromodynamics, the theory of the strong interaction, still seems to be going strong! 

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Murrough Landon and Manuel discussing results from the beam splashes

From ATLAS Around the World: Triggers (and dark) matter

27th July 2015To the best of our knowledge, it took the Universe about 13.798 billion years to allow funny looking condensates of mostly oxygen, carbon and hydrogen to ponder on their own existence. Some particularly curious specimens became scientists, founded CERN, dug several rings into the ground near Geneva, Switzerland, built the Large Hadron Collider, and also installed a handful of large detectors along the way.

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Inclusive-jet cross sections as a function of the jet pT

First measurements set the stage for early searches of new physics

24th July 2015Jets are collimated sprays of hadrons generated from quarks and gluons, produced either directly in the proton-proton collision or as a part of the decay of W bosons, Z bosons, Higgs bosons, top quarks or new particles yet to be discovered. In fact, all W, Z and Higgs bosons decay most often to quarks which form jets. 

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