Abstract
The Standard Model, the accepted theory of particle physics has had an unbroken stream of successes although, as discussed in Chap. 7, there is one tantalizing result in disagreement. It is one of the most successful theories ever proposed. There are, however, things that it does not explain and so physicists have proposed various theories that go beyond the Standard Model. One of these is Supersymmetry. In this chapter we give an introduction to that theory and discuss one of the many experimental searches for evidence of theory, or at least hints toward its structure, all of which have been unsuccessful. We argue, however, that this pursuit, although still ongoing, has been a success.
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Notes
- 1.
As discussed in Chap. 7, there is now one tantalizing result that stands in conflict with the predictions of the SM.
- 2.
The Higgs boson plays a central role in the mechanism that generates the masses of the fundamental particles that make up the constituency of the SM, where that mass is a manifestation of potential energy transferred to these fundamental particles when they interact with the Higgs field. Thus, solving the puzzle of its smaller than anticipated mass is almost automatically pursuit worthy.
- 3.
- 4.
In addition to the success of SUSY with regard to the Higgs Boson, “it is intriguing that a weakly interacting, (meta)stable supersymmetric particle might make up some or all of the dark matter in the universe. In addition, SUSY predicts that gauge couplings, as measured experimentally at the electroweak scale, unify at an energy scale … near the Planck scale” (Buchmuller & de Jong 2020, p. 1).
- 5.
- 6.
For details Franklin and Laymon (2021, pp. 31–57).
- 7.
- 8.
For a brief review of these developments see Allanach and Haber (2019, p. 25).
- 9.
There have been numerous unsuccessful searches for physics beyond the Standard Model. As of 2018 the CMS collaboration at CERN had conducted 210 such searches. In addition, there were a similar number performed by the ATLAS collaboration.
- 10.
This depends, of course, on the intensity of the proton beams.
- 11.
A trigger system includes counters and other detectors along with computer programs for making a fast decision on whether to record the data for each event.
- 12.
η is a measure of how close the jet is to the forward direction where the detector does not have coverage. η = 0 corresponds to an angle of 90° with respect to the beam. η = ∞ is along the beamline.
- 13.
PF is Particle Flow, an algorithm used to identify particles.
- 14.
The estimation of background is quite technical and will not be discussed here.
- 15.
This is known as the “look elsewhere” effect.
- 16.
There are, however, some instances which indicate “that care must be taken when interpreting results from the LHC searches and there are still several scenarios where sparticles below the 1 TeV scale are not excluded, even when considering the most recent results at √s = 13 TeV” (Buchmuller & de Jong, 2020, p. 23).
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Laymon, R., Franklin, A. (2022). Supersymmetry and the Expansion of the Standard Model. In: Case Studies in Experimental Physics. Synthesis Lectures on Engineering, Science, and Technology. Springer, Cham. https://doi.org/10.1007/978-3-031-12608-6_6
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