From The Observer
In the summer of 2012, it made international headlines: scientists at the European Center for Nuclear Research (CERN) discovered the elusive Higgs boson, a sub-atomic particle that gives matter its mass, using a particle detector called the Compact Muon Solenoid (CMS). Among the researchers who discovered it were several Notre Dame professors, research faculty and students of high-energy physics.
Now, due to a three-year, $2.4 million grant from the National Science Foundation (NSF), that group will be able to continue its research on the Higgs boson and other areas of particle physics.
Notre Dame physics professor Colin Jessop, one of the four principal investigators of the group, said the grant represents an unusual increase in funding from previous years, when funding for the NSF itself has been cut by 12 percent.
“We’ve been quite successful recently. We’re part of the team that discovered Higgs boson … because we were successful, we were able to argue for a little bit of an increase in funds, and we were successful in doing that,” Jessopsaid.
The majority of the grant, Jessop said, will go to the salaries of the research faculty and graduate students who design components of the CMS and analyze data, both at Notre Dame and at CERN in Switzerland.
The people supported by the grant have a variety of different roles in the CSM’s operation, Jessop said. The principal investigators, including Jessop, Dr. Michael Hildreth, Dr. Kevin Lannon and senior member Randy Ruchti, work with the electromagnetic calorimeter (ECAL).
The ECAL measures the energy of the photons and electrons that collide in the Large Hadron Collider (LHC), according to Jessop. It is made of crystals which, send a light signal to an electronic system when a particle enters, allowing researchers to analyze the data produced. Notre Dame researchers helped to develop a “trigger” system, which identifies significant particle collisions, he said.
The grant will also fund two research faculty members, Dr. Nancy Marinelli, who designed important software for theCSM’s readout system and is currently at CERN, and Dr. Dan Karmgard, who works with the research laboratoryQuarkNet in South Bend.
The lab, which consists of researchers, engineers, technicians and local high school students, develops and improves the components and readout system of the CMS’s hadron calorimeter, which measures the collisions of particles such as protons and neutrons, according to Karmgard.
“What we’ve been doing down at the lab for the past several years and what we continue to do is to test new materials to see if they transmit light better,” Karmgard said. ”We’re testing these new electronics to see if they work as well as we think they should, and how they [could] work better.”
Most of the rest of the grant money will support graduate students, who split time between CERN and Notre Dame and do much of the data analysis that produces findings such as the Higgs boson, as well as the ground work that keeps the CSM running.
Graduate student Andrew Brinkerhoff, who studies the properties of decaying Higgs boson particles, said to get the data, each part of the detector must operate correctly, which requires the efforts of hundreds of students.
“It kind of breaks down into two pieces. One is the design and operations of different parts of the detectors [such as] the day-to-day monitoring of the detector while it’s running, which requires 24-hour shifts,” Brinkerhoff said. “We all took shifts at one point or another while we were at CERN. The main reason to go over there is that you really have to be on the ground in the building, right over top of the detector while you’re monitoring everything that’s going on.”
The LHC, which runs continuously for months at a time, is currently shut off and awaiting improvements that will allow it to operate at full capacity, Jessop said. This allows the different subsets of the investigation group to continue working on the other aspects of the project, such as testing new materials, finalizing data analysis and planning future investigations.
“There are two purposes [of the continuing research],” Jessop said. “One is to precisely measure the Higgs boson, because that potentially tells us even more about these other new particles, and also to search for these other new particles that we think will be there. And if we discover these particles, it might be an even bigger discovery than the Higgs boson, which is a big discovery in itself.”