A search is presented for a massive particle, generically referred to as a Z′, decaying into a t-tbar pair. The search focuses on Z′ resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay…
The production of b jets in association with a Z/γ* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive production rates for Z/γ* + b-jet is…
Results are presented from a search for heavy bottom-like quarks, produced in pairs in pp collisions at √s = 7 TeV, undertaken with the CMS experiment at the LHC. The b′ quarks are assumed to decay exclusively to a top quark and a W boson (tW). The…
A study of dijet production in proton-proton collisions was performed at √s = 7 TeV for jets with pT > 35 GeV and |y| < 4.7[1] using data collected with the CMS detector at the LHC in 2010. Events with at least one pair of jets are denoted as…
Results are presented from a search for new physics in which the final state contains a photon (γ) and missing transverse energy (MET). The data correspond to an integrated luminosity of 5.0 fb−1 (inverse femtobarns) collected in pp collisions at √s…
The LHC provides CMS with millions of collisions each second, and a wealth of physics data is obtained from the proton-proton interactions. In order to record all these data for analyses, all CMS sub-detectors have to be performing optimally. If you…
CMS has presented a rich variety of results at the Electroweak Interactions and Unified Theories sessions of the Rencontres de Moriond conference in La Thuile, Italy. Links to the Physics Analysis Summaries (PAS) from CMS made public in the last…
At a CERN seminar today, CMS presented results for the search for new physics in the decay of Bs and B0 mesons to two muons, taking into account all of the 4.9 fb−1 of data collected in 2011. The results — upper limits of 7.7 x 10−9 (Bs) and 1.8 x…
Spot the difference
So how did the universe evolve into this very asymmetric state, dominated by matter, if the underlying forces can barely tell the difference between the two? One possible explanation is that there exists yet another, undiscovered…
Antimatter detectives
The antimatter is missing – not from CERN, but from the Universe! At least that is what we can deduce so far from careful examination of the evidence. For each basic particle of matter, there exists an antiparticle with the…
Probing the Plasma
Lead nuclei consist of large numbers of protons and neutrons, both made up of quarks. When the nuclei collide, a range of particles will be produced, some of which are expected to behave differently if a QGP is produced and such…
Colliding heavy nuclei
Clues to the early Universe
The Universe has changed a great deal in the 13.7 billion years since the Big Bang, but the basic building blocks of everything from microbes to galaxies were signed, sealed and delivered in the…