Particle Tracks (IMAGE) DOE/Brookhaven National Laboratory Caption Inner vertex components of the STAR detector at the Relativistic Heavy Ion Collider (righthand view) allow scientists to trace tracks from triplets of decay particles picked up in the detector's outer regions (left) to their origin in a rare "antihypertriton" particle that decays just outside the collision zone. Measurements of the momentum and known mass of the decay products (a pi+ meson, antiproton, and antideuteron) can then be used to calculate the mass and binding energy of the parent particle. Doing the same for the hypertriton (which decays into different "daughter" particles) allows precision comparisons of these matter and antimatter varieties. Credit Brookhaven National Laboratory Usage Restrictions OK for use with stories about this research. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.