Fellow 2012-13

Mark Neubauer


An Integrated Approach to Understanding the Origin of Mass and Advancement in Computing and Triggering Technologies for Research in Particle Physics

Our best theory describing the fundamental particles in nature and their interactions, the Standard Model, predicts the existence of a massive particle called the Higgs boson. Despite decades of experiments at ever-more-powerful accelerators and higher collision energies, the Higgs boson remains the only Standard Model particle that has not been observed directly.

During his Center appointment, Professor Neubauer proposes to exploit unique tracking signatures common to the Higgs boson decay and develop multivariate analysis techniques to improve the sensitivity of our search for the Higgs boson. The work is part of his collaboration with the ATLAS experiment, which studies proton collisions at the world’s highest-energy particle collider: the Large Hadron Collider at CERN.

Current experimentation has narrowed the possible mass region for the Higgs boson to 114-145 GeV (low mass) or 466-1000 GeV (high mass). Professor Neubauer’s research searches in both mass regions for the decay of the Higgs boson to a pair of W bosons, where one W boson decays to a charged lepton plus a neutrino. For collision events where the other W boson decays in the same manner, he will use tracks from non-pileup interactions as an independent way to detect neutrinos in the event and distinguish true neutrino signals. For collision events where the other W boson decays to a pair of quarks that subsequently create jets of particles through a process called hadronization, he will investigate new techniques used to separate the very energetic jets coming from highly boosted W bosons characteristic of Higgs boson decay (the signal) from background processes that typically have lower energy jets.

Professor Neubauer also plans to further develop an automated Matrix Element (aME) analysis technique that improves both the low- and high-mass Higgs sensitivity by exploiting correlations among the final-state particle momenta. The aME technique automates the calculation of event probabilities for any process of interest in the Standard Model and represents a tool for the Higgs boson and for new physics beyond the Standard Model searches.