Physics Beyond Standard Model with the CMS Pixel Detector

Physics Beyond Standard Model with the CMS Pixel Detector

This award is centered on the CMS experiment currently running at the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland. The discovery of the Higgs boson at the LHC in 2012 was a crowning achievement for the Standard Model (SM), currently the best theory to describe the most basic building blocks of the universe. However, there is ample evidence that the SM does not explain, for example, the nature of the dark matter (DM) and dark energy, matter-antimatter asymmetry and neutrino oscillations, to name a few.

Physics beyond the Standard Model (BSM) refers to the theoretical developments required to explain the shortcomings of the Standard Model. The current capabilities of the LHC enable improved Standard Model measurements, BSM physics searches, studies of flavor physics of heavy quarks and leptons, properties of the Higgs boson, and matter at high density and temperature.

These could also shed light on the origins of the DM that might be concealed in as-of-yet untested BSM physics processes. In addition, to enhance its capabilities, LHC also plans its major upgrade, called the High-Luminosity Large Hadron Collider HL-LHC) that would crank up its performance by a factor of 10 beyond the current design value. There is also a planned matching upgrade of the LHC detectors.

The primary focus of this research is to exploit the capabilities of the current CMS pixel detector during LHC Run-3 to pursue BSM searches by exploring possible hidden QCD-like gauge sectors that could host strongly self-interacting DM candidates that might interact with SM particles through mediator portals and potentially be produced at the LHC. Compared to its previous iteration, the current pixel detector has an extra barrel and endcap layers, a reduced material profile, a new readout chip to minimize data losses due to high pile-up of LHC events, and an optimized detector layout for 4-pixel-hit coverage over the full CMS pseudorapidity range.

These improvements are key to the physics goals of this award as it leads to higher tracking efficiencies, lower fake-track rates, lower dead-time/data-loss, an extended lifetime of the detector, improved "particle flow" analysis and physics object identification including missing energy reconstruction. The precise measurement of 'missing energy' could unravel signatures of potentially undiscovered particles in many BSM physics processes, some of which could be candidates for Dark Matter and account for the graviton escaping in extra-dimensions or for other exotic particles possibly expected in BSM.

This effort will also include activities in development and testing of additional pixel detector upgrades designed to fully harness HL-LHC physics capabilities while maintaining support of current Pixel Detector Operations.

The spectrum of activities enabled by the above physics searches and detector work provides a fertile ground to train an advance STEM workforce. It brings an enormous opportunity of intellectual development and experience for our physics and engineering students. They would learn data analysis techniques, code related algorithms, develop software, use Machine Learning to improve physics reach and utilize LHC grid computing infrastructure.

This skill set is key to pursue successful STEM careers in academia or the private sector. The synergy of outreach activities with Quarknet, centered around the exciting science done at the LHC, promotes a strong bond of collaboration with high school teachers. It leads to strengthening of teaching skills and learning around the schools in Puerto Rico and motivating students to pursue STEM disciplines.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.