UMass Particle Physicists Receive DOE Support to Study Higgs Bosons

Stephane Willocq's research team
UMass particle physics team (not all members are in the photo)

This month the U.S. Department of Energy (DOE) announced $132 million in funding awards to researchers at more than 50 universities, including physicist Stephane Willocq and his team, who are working on topics in high energy physics. The purpose is “to advance knowledge of how the universe works at its most fundamental level.”

In addition to Willocq, his team on the ATLAS Experiment at the Large Hadron Collider (LHC) in Switzerland includes Ben Brau, Rafael Coelho Lopes de Sa, Carlo Dallapiccolaand VerenaMartinez Outschoornin the Physics Department.

The UMass Amherst team brings special expertise in identifying and measuring a class of heavy electrons called muons, fundamental particles like electrons only 200 times heavier. They are expected to offer tell-tale signs of discovery as decay products of new states of matter. The team has written much of the particle identification software for a spectrometer that reconstructs muon trajectories in space “like a connect-the-dot game using traces of energy,” Willocq says.

Among other goals, they plan to use the LHC to produce proton-proton collisions at the highest achievable energies to study the production and decay of Higgs bosons, he explains. They also will search for new phenomena that would shed light on knowledge gaps in the current understanding of the universe, including the origin of mass, or the nature of Dark Matter.

The UMass ATLAS group on campus receives about $2.3 million from DOE based on previous successful studies and with their proposal to further exploit the large dataset collected during Run 2 of the LHC from 2015 to 2018, plus other activities, Willocq says.

He adds that the plan includes analysis in the search for physics beyond the Standard Model and measuring Higgs boson properties. A second focus area is on hardware upgrade and software development for Run 3 and Run 4 that includes an upgrade to the collider at the high-luminosity Large Hadron Collider (HL- LHC).

Willocq says, “Specifically, we will work on hardware development for the all-silicon inner tracker as well as on the development of the muon trigger processor for the level-0 MDT trigger.” On the software side, they will work on tracking-related development, including completing the multi-threading migration, developing future software and computing into the HL-LHC era, and continued support and improvement of the inner tracker and muon spectrometer reconstruction.

DOE’s Under Secretary for Science, Paul Dabbar, says, “High energy physics research improves our understanding of the universe and is an essential element for maintaining America’s leadership in science. These projects at 53 different institutions across our nation will advance efforts both in theory and through experiments that explore the subatomic world and study the cosmos.”

Further, DOE observes that “high energy physics serves as a cornerstone of America’s science efforts. It plays a major role in nurturing top scientific talent and building and sustaining the nation’s scientific workforce. It also provides a deeper understanding of how our universe works at its most fundamental level.”