CERN Achieves Highest-Energy Particle Collisions Ever on Earth, Like Conditions Just after Big Bang

This new proton collision data, the first recorded since 2012, will enable an international collaboration of researchers — including many from the University of Washington — to study the Higgs boson, search for dark matter and develop a more complete understanding of the laws of nature.

“Together with collaborators from around the world, scientists from roughly a hundred U.S. universities and laboratories are exploring a previously unreachable realm of nature,” said James Siegrist, the U.S. Department of Energy’s associate director of science for high-energy physics. “We are very excited to be part of the international community that is pushing the boundaries of our knowledge of the universe.”

Members of the UW team are physics faculty members Henry Lubatti, Anna Goussioiu,Gordon Watts, Shih-Chieh Hsu and Joe Rothberg, post-doctoral researchers Emma Toro, Nikos Romptois and Lynn Marx and graduate students Heather Russell, Rachel Rosten, Pedro De Bruin and Nikola Whallon. The graduate students and post-doctoral researchers are currently working at CERN.

The Large Hadron Collider, the world’s largest and most powerful particle accelerator, reproduces conditions similar to those that existed immediately after the Big Bang.

In 2012, during the collider’s first run, scientists discovered the Higgs boson — a fundamental particle that helps explain why certain elementary particles have mass. U.S. scientists represent about 20 percent and 30 percent, respectively, of the ATLAS and CMS collaborations, the two international teams that co-discovered the Higgs boson. Hundreds of U.S. scientists played vital roles in the Higgs discovery and will continue to study its remarkable properties.

Scientists will use the new data to pin down properties of the Higgs boson and search for new physics and phenomena such as dark matter particles — an invisible form of matter that makes up 25 percent of the entire mass and energy of the universe.

Physicists will also endeavor to answer questions like: Why is there more matter than antimatter? Why is the Higgs boson so light? Are there additional types of Higgs particles? What did matter look like immediately after the Big Bang?

The collider was turned off in early 2013 and engineers spent two years preparing the machine to collide particles at a much higher energy and intensity. During the shutdown U.S. scientists and their international collaborators installed several new components in the four LHC detectors, including components for the ATLAS detector designed and fabricated by the UW team.

These components, together with other upgrades, will allow physicists to record more information about the particles produced during the high-energy collisions.

“The University of Washington is a key player, in the sense that we contributed enormously to the design and fabrication of the ATLAS detector at the beginning,” said Lubatti. “And we have recently contributed a new detector that will enhance our ability to make discoveries by making measurements very close to the collision point of the protons.

“Having a measurement so close to the collision point greatly increases our ability to identify particles that may be indicators leading to new discoveries. This will enhance our understanding of the fundamental interactions that define the building blocks of matter in the universe,” said Lubatti, who will soon join his colleagues in Geneva, Switzerland.

“The first three-year run of the LHC, which culminated with major discovery in July 2012, was only the start of our journey. It is time for new physics!” said Rolf Heuer, CERN director-general, in a statement. “We have seen first data beginning to flow. Let’s see what they will reveal to us about how our universe works.”