On March 30, physicists in Geneva successfully smashed together two proton beams energized with seven trillion electron volts, breaking the previous world record by 350 percent and setting the stage for new insights into the forces of nature and full dimensions of space. The breakthrough marks an important step forward for Columbia physicists, who have played a significant role in carrying out the experiment.
A U.S. research team of more than 500 physicists, led by Columbia physics professor Michael Tuts , has been responsible for operating ATLAS, one of four particle detectors that recorded and analyzed debris from the collisions. The U.S. physicists are part of an international team of some 2,500 researchers working on ATLAS. The data resulting from the detector will allow researchers to explore more deeply some of the most vexing mysteries of the physical universe, such as the nature of dark matter and the origins of mass.
“We are all very excited to see these first collisions that mark the start of the real physics program and the culmination of more than a decade of effort in building the ATLAS detector and Large Hadron Collider,” said Tuts.
The Large Hadron Collider experiment began last November, when the first circulated beam—the width of a strand of hair—was launched with 450 billion electron volts of energy. The collider quickly set a world-record launch of 1.18 trillion electron volts per beam, surpassing the record set by the Illinois-based Fermi National Accelerator Laboratory, run by the U.S. Department of Energy. The March 30 collisions shatter those records, with a launch of 3.5 trillion electron volts per beam.
During the collision, two proton beams were propelled by more than a thousand powerful superconducting magnets at nearly the speed of light. Only a split-second had passed before the resulting explosion of hundreds of particles deep inside the Large Hadron Collider, a ring-shaped accelerator buried 300 feet underground. The collider is 16 miles in circumference and resides near the Swiss-French border. Built by the European Organization for Nuclear Research (a particle-physics laboratory also known as CERN), it is the world’s largest particle accelerator and arguably the most complex scientific instrument ever created.
The Columbia team consists of 20 physicists, including faculty, postdoctoral students and graduate students. Professor John Parsons was responsible for the construction of about 1,600 electronics modules that measured the energy of particles captured by ATLAS. Professor Gustaaf Brooijmans is responsible for designing new electronics for future upgrades of the detector, and professor Emlyn Hughes played a key role in measuring the trajectories of the particles using a silicon detector. William Willis , Higgins Professor of Physics, oversaw the decade-long contruction project for the U.S. contributions to the ATLAS detector.