The announcement last week that scientists have observed a new particle that may be the elusive Higgs boson spelled success for Indiana University researchers who worked for years on a massive experiment that detected the particle.
Representatives of two experiment teams, ATLAS and CMS, said July 4 in Geneva, Switzerland, that they had observed a new particle in the mass region around 125-126 GeV, consistent with expectations for the Higgs boson. The experiments have been conducted over several years at the Large Hadron Collider operated by CERN, the European Organization for Nuclear Research.
IU’s participation in the Large Hadron Collider included leadership by IU physicists who designed and built a key component of the ATLAS detector mechanism and by information technologists who ensured the availability of vast computing resources used to analyze data from the experiment. This collaboration by scientists and information technologists represents one of IU’s key strengths in scientific research, and has enabled IU to be a particularly valuable partner in an international collaboration that involves thousands of people overall.
The LHC facility is one of the largest experimental facilities ever built — 17 miles in circumference, 300 feet underground, lying beneath the territory of France and Switzerland.
“As a great university, Indiana University pursues age-old and deepest questions such as ‘Why is there something, rather than nothing?'” said IU President Michael A. McRobbie. “With this most recent announcement we congratulate IU physicists for their leadership in helping us understand — at least at a physical level — why there is something, and the fundamental properties of the matter that makes up that something. IU also constantly pursues new technological innovations, and we are thrilled that IU’s information technology prowess aided in this discovery.”
Discovery of the Higgs boson would fill a crucial gap in the Standard Model, which describes the fundamental particles from which everything in the universe is made and the forces acting between them. The Higgs boson explains why fundamental particles have mass; without it, particles would whiz around at the speed of light and not be able to bind to form protons, neutrons, atoms, stars and the material of the universe, including us.
“What ATLAS is seeing is a very strong indication that the Higgs boson exists at a mass of approximately 134 times that of the proton,” said physicist Harold Evans, principal investigator for IU’s ATLAS team. “This is interesting because it validates our current understanding of the micro-world of fundamental particles and the forces that govern them, and also because it may point us to a more complete theory that describes particle interactions at even higher energies and smaller distance scales.”
Researchers and staff from the Department of Physics in the IU College of Arts and Sciences, led by professor Harold Ogren, were responsible for the design and construction of a critical part of the ATLAS experiment’s equipment, called the Barrel Transition Radiation Tracker. This tracker is about as tall as a person and weighs almost a ton. It is part of the ATLAS detector, which like the CMS detector is installed in CERN’s massive LHC facility. Much of the Barrel Transition Radiation Tracker was constructed on the IU Bloomington campus.
“This is a proud day for all of the students, technicians and engineers who worked for many years in Bloomington on the TRT tracker,” Ogren said. “Finding the Higgs with the help of our tracker is a dream come true and a high point in my physics career.”
For Evans, who has been at CERN since mid-May, the build-up to last week’s announcement was the most exciting time in his career as a physicist.
“The level of anticipation and intensity at the lab has been simply incredible,” he said. “Meetings of the analysis teams at all times of the day and night, animated discussions over coffee, rumors and hints of what our competitors are seeing — all of these made CERN the best place in the world to be for me. I was very lucky to be there and to be a part of it all.”
IU physicist Sabine Lammers said the discovery announced last week is the beginning of a rich period of investigation for particle physics.
“It really is just the beginning of the Higgs era, even though it is the ‘final’ piece of the Standard Model puzzle,” she said. “We will be very eager to see what the properties of this new particle will be, and whether there is a single Higgs boson or several.”
“The Large Hadron Collider is the original ‘big data’ project, with massive computing power required to transmit and analyze the petabytes upon petabytes of data produced by the experiments,” said Craig Stewart, executive director of the Pervasive Technology Institute and associate dean of research technologies. (A petabyte of data on compact disks would make a stack miles high).
The data produced by the LHC is analyzed on an international computing grid called the Open Science Grid. IU’s Pervasive Technology Institute runs the operations center for the Open Science Grid and is responsible for ensuring that this grid is at work processing data 24 hours a day, 365 days a year.
IU also partners with the University of Chicago in managing the Midwest Tier2 computing center, one of the main processing facilities within the Open Science Grid. The Midwest Tier2 Center has computing clusters at IU Bloomington, Indiana University-Purdue University Indianapolis, and Chicago. This center is one of only five such centers dedicated to processing ATLAS data in the U.S. The University Information Technology Services GlobalNOC (Network Operations Center) plays an important role facilitating movement of data from Europe to the U.S. and distribution of data throughout the U.S. over high-speed international and national networks.
IU physicists have also contributed to research efforts aimed at testing the Standard Model through the DZero project, taking place at the Tevatron collider at the U.S. Department of Energy’s Fermi National Accelerator Laboratory near Chicago.
“It’s fantastic that, after many years of collecting data with the DZero detector at the Tevatron, we now have an excess pointing toward evidence of the Higgs decaying into a pair of heavy quarks, demonstrating that the Higgs boson indeed ‘couples to mass’ and showing that it can be responsible for generating the masses of all particles,” said IU physicist Rick Van Kooten.
Story courtesy of The Herald-Times, written by Steve Hinn