The production of a W boson in association with “jets” of particles initiated by quarks or gluons (“W+jets” events) is an important signature to test quantum chromodynamics, the theory of strong interactions. A new measurement reported by ATLAS focuses on studying the properties of the jets in a large data sample of W+jets events.

ATLAS has observed a particle state of mass and decay properties consistent with expectations for an excited state of the Bc meson. The discovery follows analysis of the full 7 TeV and 8 TeV proton-proton collision data sets from the LHC’s first run.

The ATLAS Collaboration has analyzed its full Run 1 data sample of seven and eight TeV (tera electron Volts) proton-proton collisions delivered by the Large Hadron Collider (LHC), to produce an accurate measurement of the Higgs boson mass. The Higgs boson resonance appears as a narrow peak in the mass spectra of its decays to two photons or to four charged leptons, as shown in the two figures below.

Using the full data sample from the LHC’s first run of proton-proton collisions, ATLAS has measured the production rate of top and anti-top quarks.

Evidence for the production of a W or Z boson together with a top quark pair, referred to as tt̄W and tt̄Z processes, has been found in the ATLAS analysis of the 8 TeV data from the LHC’s first run.

Every other year, particle physicists gather together to share their latest results at the ICHEP (International Conference on High Energy Physics) conference. This year, more than 700 are attending the conference in Melbourne, Australia, July 4-11.

Where to begin? The 4th of July, 2012 will remain burned in the memories of those of us fortunate to be delegates at this historic 36th International Conference on High Energy Physics (#ICHEP2012) in beautiful Melbourne, Australia.

Every other year, particle physicists gather together to share their latest results at the ICHEP (International Conference on High Energy Physics) conference. This year, more than 700 are attending the conference in Melbourne, Australia, July 4-11.

The ATLAS Experiment will be presenting its most recent results from searches for the Higgs Boson at the LHC in a dedicated seminar to be held at CERN on 4 July at 9:00 CET.