On the hunt for ‘exotic’ matter

MCGILL U. (CAN) — Researchers used Einstein’s famous E=mc2 equation and the Large Hadron Collider in Switzerland to recreate a miniature version of the event at the origins of the universe.

The first findings from the experiment, known as ATLAS, are reported this week in the journal Physical Review Letters.

Andreas Warburton, a physicist at McGill University, and 3,171 colleagues from around the world are using the data collected from the recreation in an attempt to look for exotic new particles whose existence is suggested by theoretical calculations.

“Understanding whether new kinds of matter exist or not is interesting because it holds clues to knowledge about how the universe works fundamentally,” Warburton says.

“The standard model of particle physics is a useful theoretical framework but it is known to be flawed and incomplete—we are searching for new particles that lie outside this framework, and we are also seeking to establish the non-existence of these hypothetical particles.”

The new published findings fall into the latter category and are about determining the mass of a theoretical particle known as an “excited quark.”

“By exploring the high-energy subatomic frontier, it is metaphorically somewhat like turning over stones at the seashore and looking for new and interesting surprises hiding under the rocks,” Warburton explains.

“Here we are looking under stones that have been too heavy to lift before this summer. What we see or don’t see under those stones helps to paint new pictures about how the universe works and tells us which stones are most important to look under next.”

Warburton says the results have been highly anticipated by many people. “There was friendly competition amongst us as to who will be the first to make a publishable measurement that either excludes or discovers ‘new physics,’ and I am proud that the ATLAS team won this race.”

More news from McGill University: www.mcgill.ca/newsroom/