Overview: Fundamental goals of the experiments at the Large Hadron Collider at CERN, the Center for Particle Physics in Europe, located in Geneva, Switzerland are to understand the nature of the Higgs Boson, recently discovered there in 2012, and to discover new physics beyond the Standard Model of Elementary Particle Physics. These goals are relevant to the understanding of the Universe at its most fundamental level just in the fleeting fraction of a second just after the Big Bang, and to why we see the Universe as we do now. To meet the challenges of this quest, new theories are advanced, new detectors and accelerators are developed and built, and new computing and analytical methodologies are created, all of which have significant broader impact for the training of young scientists in the near term and the advancement of technological benefits to society over the longer term. Over a thousand scientists from the United States are involved with this scientific program on several major experiments.
Intellectual Merit: Among the important outstanding questions is why the observed mass of the Higgs boson is so low, found to be 126 billion electron volts, or roughly 135 times the mass of the proton. In fact this low mass value is one of the most profound conundrums in all of science and is currently driving much of the scientific discourse in the field of particle physics. Certain extended models of Supersymmetry, such as the Next-to-Minimal Supersymmetric Model (NMSSM), are theoretically attractive and can accommodate the observed low value of the Higgs Mass.
Through this award, Professor Andrew Haas and his group at New York University will conduct analytical searches for this new physics using the data from the ATLAS experiment, one of the major multipurpose detectors at CERN. They will probe into the domain of Higgs physics, searching for the decays of Higgs bosons into pairs of special, low mass particles called "a" bosons and into the domain of extended supersymmetry such as the NMSSM. The PI has performed such searches already at the Tevatron Collider at Fermi National Accelerator Laboratory, Batavia, IL, with data from the Dzero Experiment, but the group expects the ATLAS data to provide 10 times better sensitivity.
The NYU group will also search for long-lived "meta-stable" new particles decaying in the inner tracker of ATLAS, in events with missing transverse energy, using simulation and reconstruction techniques developed by Haas. This analysis could form the basis for possible future searches for non-Standard Model Higgs boson decays to new, long-lived particles.
Broader Impact: Exciting discoveries at the LHC have created a special opportunity to interact with the public and students. Haas has an established track record of incorporating undergraduates in his research program in effective ways. Importantly, the group will work with local New York City high schools, to attract motivated students to engage in summer research projects using the ATLAS data.