Observing a phenomenon for the first time helps us fine-tune our understanding of the Universe. CMS physicists found such a phenomenon in September 2012 in proton-lead collisions, an observation that has since been reinforced by much more data from such collisions collected in early 2013.

CMS measures production rates up to high transverse momenta

Sometimes, everyday words are co-opted by scientists and used as technical terms. One of these is the word “berry”.

New results on the Higgs boson, Standard Model physics, and searches for exotic physics

New results on the Higgs-like boson, Supersymmetry, and searches for exotic physics

The new year brings a new type of collision at the LHC: the accelerator will smash protons and lead nuclei together, allowing CMS and the other LHC experiments to study the cold nuclear matter we expect these collisions to produce.

In 2011, CMS presented early evidence that Upsilon (Υ) particles produced in lead-lead collisions “melt” as a consequence of interacting with the hot nuclear matter created in these heavy-ion interactions

Kyoto, Japan on 12–16 November 2012

Amongst all known elementary particles, the top quark is peculiar: weighing as much as a Tungsten atom, it completes the so-called 3rd generation of quarks and is the only quark whose properties can be directly measured.

CMS has published its first paper on proton-lead (pPb) collisions, describing the observation of a phenomenon that was previously seen first in nucleus-nucleus collisions but also detected by CMS in proton-proton (pp) collisions.

All of the atoms in our bodies are made of electrons, protons and neutrons, and the protons and neutrons can be further broken down into quarks. Fundamentally, then, we are made of only two types of particles: electrons and quarks. But what do these labels mean?

Our best understanding of the early Universe tells us that a dense medium, known as the quark-gluon plasma (QGP), existed in the first microseconds after the big bang.

The Quark Matter 2012 conference, held in Washington DC from 13-18 August 2012, brings together experimental and theoretical experts in the area of heavy-ion physics.

31 July 2012, CERN

Jets are the experimental signatures of quarks and gluons produced in high-energy processes such as head-on proton-proton collisions.

The search for microscopic black holes at the LHC is motivated by the hierarchy problem — the huge observed difference between the strengths of the electroweak and gravitational forces.

A measurement of the underlying event (UE) activity in proton-proton collisions at a centre-of-mass energy of 7 TeV is performed using Drell-Yan events in a data sample corresponding to an integrated luminosity of 2.2 fb⁻¹

New, excited Ξ^*_b⁰ baryon observed with more than 5 standard deviations significance at a mass of 5945.0 ± 2.8 MeV.

A search is presented for a massive particle, generically referred to as a Z′, decaying into a t-tbar pair.

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.

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).

Results are presented from a search for new physics in which the final state contains a photon (γ) and missing transverse energy (ME_T).

A study of dijet production in proton-proton collisions was performed at √s = 7 TeV for jets with p_T > 35 GeV and |y| < 4.7[1] using data collected with the CMS detector at the LHC in 2010.

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.

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.

At a CERN seminar today, CMS presented results for the search for new physics in the decay of B_s and B⁰ mesons to two muons, taking into account all of the 4.9 fb⁻¹ of data collected in 2011.

Spot the difference

Antimatter detectives

Probing the Plasma