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Āé¶¹¹ŁĶų Alum Uses AI to Advance CERNās Search for New Particles
By Kirsten Heuring Email Kirsten Heuring
- Associate Dean of Marketing and Communications, MCS
- Email opdyke@andrew.cmu.edu
- Phone 412-268-9982
Āé¶¹¹ŁĶųās Abhirami Harilal is helping physicists hunt for new particles that could unlock one of the universeās biggest mysteries: dark matter.
During her four years at CERN, Harilal used machine learning to improve how physicists detect rare particle signatures, which has sharpened the Large Hadron Colliderās search. Along the way, she also upgraded CERNās detector technology by developing algorithms now deployed inside the Compact Muon Solenoid (CMS) experiment to autonomously identify anomalies more accurately than ever before.
āThere are still many fundamental questions about the universe that current physics canāt fully explain,ā said Harilal, who graduated from Carnegie Mellon with a Ph.D. in physics. āAt the Large Hadron Collider, weāre searching for signs of new particles that could help answer them.ā
Only about 5 percent of the universe is made of matter, which people can see with their own eyes or detect using scientific equipment. The rest of the universe consists largely of dark matter and dark energy, which researchers are unable to observe through traditional methods. Though these forces are unseen, they affect the movement of galaxies, stars and planets.
Researchers at CERN are working to understand what these particles are and how they behave. In 2012, they discovered the Higgs boson, a particle that represents the physical manifestation of a quantum field permeating the universe.
āThe Higgs boson takes a very special role in what we know about fundamental particles, and many theories suggest that if new particles exist, they could be connected to the Higgs boson,ā Harilal said. āI was trying to see if this Higgs boson would give way or decay into a new particle called an A particle, which could be connected to dark matter or other hidden sectors.ā
Harilal used machine learning models to improve how researchers detect the A particle. She used computational modeling to simulate thousands of particle collisions similar to those produced at the LHC. Using these methods, Harilal improved the experimentās sensitivity to particles with unusual or hard-to-detect signatures, including potentially the A particle.
In addition to conducting her own research, Harilal also improved CERNās CMS detector using similar machine learning methods. When Harilal first arrived at CERN, the detectorās data monitoring system could flag unusual activity in the data but had criteria that could miss subtle or changing anomalies. Researchers often had to manually compare the flagged data known, reliable datasets to pinpoint the anomalies.
Harilal developed a machine learning model to automate the process, not only alerting the researchers to unusual activity but also identifying how the data differed from expected results. Her work has made it easier for CERN scientists to diagnose potential issues as they gather data.
āIām particularly proud about it because this was actually deployed and used during live data taking,ā Harilal said.
Harilal's advisor Manfred Paulini, professor of physics and Mellon College of Sciences Associate Dean for Research, said Harilalās work helped make progress both in physics and in machine learning.
āI feel very fortunate to work with exceptional graduate students like Abhirami, who are not only experts in particle physics research but also operate at the forefront of developing machine learning algorithms,ā Paulini said. āThroughout her Ph.D. in high energy physics, Abhirami cultivated a broad set of technical and professional skills that are directly transferable to solving real-world challenges.ā
Harilal is assisting other projects related to the CMS from Pittsburgh. Once she is done with her research, she said she hopes to apply her machine learning skills to other areas in research or industry.
āA big part of my work is recognizing meaningful patterns in large amounts of noisy data, which is also relevant in many other applications,ā Harilal said. āSimilar ideas apply in areas like medical imaging, financial data, drug discovery. Iām looking forward to finding other opportunities to use these skills.ā