University of Minnesota
School of Physics & Astronomy


Undergraduate research at the Large Hadron Collider

Kelly Stifter at the Large Hadron Collider in CERN Switzerland
Kelly Stifter at the Large Hadron Collider in CERN Switzerland

Kelly Stifter is an undergraduate physics and math major who is currently working at the Large Hadron Collider (LHC) at CERN in Switzerland. The Large Hadron Collider was shut down for upgrades from February 2013 until March 2015. During this time, hundreds of physicists worked to improve the performance of the machine. The collider will begin working up to 13TeV, the highest energy yet created in a particle accelerator. This new energy means that the monitoring and safety systems needed to be improved as well.

Stifter is finishing a semester working on the beam halo monitor (BHM) which is a detector just outside the Compact Muon Solenoid experiment. The BHM monitors the quality and stability of the beam. She is part of a team that worked on and installed the monitor in mid-March, 2015. A clean beam is important to the safe and effective operation of the LHC. With huge energies created in the acceleration of protons, the system known as the collimator controls the size of the beam, in doing so it can create extra radiation which can interfere with the detector. Stifter says that too many stray protons are capable of damaging the superconducting magnets which steer the beam.

When Stifter arrived at CERN she says that she acted as an assistant to the graduate students that were working on the beam monitor, but by the end of her tenure she felt like had learned enough to be a full member of the team. She recently participated in the first splash event after the start up. This particular test was to see how the BHM functioned in action. It’s called a “splash event” because the operators deliberately crash a beam of protons into the collimator and measure the “splash” created by the event. These tests are important for calibrating and commissioning the detector because they make sure the system is fully functioning with real data rather than simulation data. More recently, Stifler was on hand to witness the first collisions at 9000 GeV.

Stifter’s work at the LHC has been the cap to an impressive undergraduate academic career. She received the Henry and Viola St. Cyr Scholarship for Summer Research, which allowed her to take a position at the Soudan Underground Laboratory in Northern Minnesota, working with Professor Priscilla Cushman on the Cryogenic Dark Matter Search. “Awards have been crucial for me because they allow me to focus on my studies.” Stifter said that award money allowed her to have a stress-free education. “I cannot say how much of a relief it is to be able to put more time into classes, student groups and outside research. Stifter also participated in Engineers without Borders and helped recruit honors students who were entering the program. She was accepted at nine out of the eleven graduate schools she applied to, eventually choosing to pursue a Ph.D. in particle physics at Stanford. She said that her choice of graduate program was also informed by her time at CERN. “That’s been another advantage to my time at the LHC. I get to talk to post docs and professors from everywhere, people at the very top of the particle physics world.”