Advanced research projects

The International Particle Physics Outreach Group (IPPOG) has developed an educational activity that brings the excitement of cutting-edge particle physics research into the classroom. The ATLAS group at the University of Oslo has developed the Z-path, a powerful and popular educational tool allowing high-school students to learn about particle physics, master concepts of 'event' and 'statistics', and search for new phenomena using real LHC proton-proton collision data. By studying collision events students use the invariant mass technique to identify short-lived particles that decay into 2 leptons, whose properties are recorded by the detector. A few properties of some particles, such as mass and lifetime, can be inferred. The students distinguish between the Z boson - one of the mediators of the weak force - and other particles made of quarks. Furthermore, they apply the same technique to search for new particles, such as the Z’ - the mediator of a new hypothetical force. The ambition to bring important LHC discoveries to the “classroom” is realized using the discovery of the Higgs boson in 2012. Approximately 10% of the ATLAS Run 1 discovery data at 8 TeV centre of mass energy are made available for students to search themselves for the Higgs boson. The work has been presented at various international conferences .


New features concern more advanced students and include missing energy-momentum (a key concept closely related to dark matter); Supersymmetry (Susy); and other exotic phenomena such as extra space dimensions. We propose 3 projects where one or 2 students per project will analyse LHC proton-proton collision data and investigate these topics in detail. A new platform gives access to real data recorded by the ATLAS detector.  A set of Monte Carlo simulation samples can be used to compare measurements to some theoretical predictions. In addition to a web-based analysis, software tools allow the students to write their own analysis programs. The goal is to study Standard Model (SM) processes and search for new physics phenomena: new particles, new fundamental forces.

Several projects are proposed. Each analysis consists of (i) selecting and studying particular final states made of particles measured by the detector, (ii)  identifying the underlying  proton-proton collision process(es), and (iii) interpreting the results in terms of SM measurement or within some new theory.

An introduction and short demo/tutorial will be given at the beginning to all students involved in the ATLAS-related projects.

What do 4-lepton final states tell us about the Standard Model and the Higgs boson?

(i) Four charged lepton final state. (ii) pp→ ZZ+X → 4l+X or pp→ H+X→ ZZ+X → 4l+X. X indicates particles needed to satisfy the basic conservation rules. (iii) Test of the electroweak theory and production and study of the Higgs boson.

Do new fundamental forces or extra space dimensions show up at the LHC the way the Z and Higgs bosons did?

(i) Dilepton and diphoton final states. (ii) pp→ γ,Z, Z’,G→ l+l- +X , pp→H,G→γγ + X. (iii) Study of known particle resonances, search for new ones in dilepton and diphoton invariant masses, make use of spin to distinguish various outcomes.

Is the world supersymmetric and/or where is Dark Matter?

(i) Dilepton and missing transverse energy (MET) final state. (ii) pp→~l+~l-+X→ l+l-+MET+X, pp→Z+MET+X→ l+l-+MET+X, pp→W+W-+X→ l+l-+MET+X, pp→Z(→l+l-)  Z(→νν)+X→ l+l-+MET+X. (iii) Search for Susy particles (sleptons) and/or Dark Matter.

Published May 11, 2017 6:25 PM - Last modified Nov. 27, 2018 11:29 AM