The ALICE experiment at CERN has announced the direct observation of jet quenching, a phenomenon that gives scientists more insight into the early beginnings of matter in the universe. This announcement comes just weeks after the LHC first began colliding lead ions. The results of the experiments have been reported in a paper recently accepted for publication by Physical Review Letters.
“Jet quenching” describes the characteristic signal that the basic constituents of matter give off in both the ATLAS and CMS detectors. Scientists credit this phenomenon with the recent increase in the number of particles produced in the lead ion collisions, as well as the hot plasma the LHC produces that behaves like a perfect fluid.
“ATLAS is the first experiment to report direct observation of jet quenching,” said ATLAS Spokesperson Fabiola Gianotti. “The excellent capabilities of ATLAS to determine jet energies enabled us to observe a striking imbalance in energies of pairs of jets, where one jet is almost completely absorbed by the medium. It’s a very exciting result of which the Collaboration is proud, obtained in a very short time thanks in particular to the dedication and enthusiasm of young scientists.”
CMS Spokesperson Guido Tonelli said that a future challenge will be to combine all possible studies to get a clearer understanding of this new property’s state of matter.
The latest observation moves the LHC forward in its goal to utilize its lead-ion program to uncover the mysteries of matter as it existed in the universe’s earliest moments.
