Physicists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Stony Brook University (SBU) have shown that particles produced in collimated sprays called jets retain information about their origins in subatomic particle smashups. The study was recently published as an Editor’s Suggestion in the journal Physical Review Letters.

“Despite extensive research, the connection between a jet’s initial conditions and its final particle distribution has remained elusive,” said Charles Joseph Naim, a research associate at the Center for Frontiers in Nuclear Science (CFNS) in SBU’s Department of Physics and Astronomy. “This study, for the first time, establishes a direct connection between the ‘entanglement entropy’ at the earliest stage of jet formation and the particles that emerge as a jet evolves.”

The evidence comes from an analysis of jet particles emerging from proton-proton collisions captured by the ATLAS experiment at the Large Hadron Collider, a 17-mile-circumference circular collider located at CERN, the European Organization for Nuclear Research. In these powerful collisions, the individual building blocks of the colliding protons, known as quarks and gluons, scatter off one another and sometimes get knocked free with enormous amounts of energy. But quarks can’t stay free for long. They and the gluons that normally hold them together immediately begin to split and reconnect through a branching process called fragmentation. The result is the formation of many new composite particles made of pairs or triplicates of quarks—collectively known as hadrons—that spray out of the collision in a coordinated way, that is, as a jet.

Physicists have scaled down the maximum possible mass of an elusive “ghost particle” called a neutrino to at least one-millionth the weight of an electron. The revision takes scientists one more step toward a discovery that could alter or even upend the Standard Model of particle physics.

Our universe is awash with phantom specks of matter. Every second, around 100 billion neutrinos pass through each square centimeter of your body. They’re produced in multiple places: the nuclear fire of stars, in enormous stellar explosions, by radioactive decay and in particle accelerators and nuclear reactors on Earth.

Even though they’re the most common form of matter in the cosmos, neutrinos’ minimal interactions with other matter types makes them notoriously difficult to detect, and they’re the only particles in the Standard Model whose precise mass remains unaccounted for.

Top minds at the world’s largest atom smasher have released a blueprint for a much bigger successor that could vastly improve research into the remaining enigmas of physics.

The plans for the Future Circular Collider—a nearly 91-kilometer (56.5-mile) loop along the French-Swiss border and below Lake Geneva—published late Monday put the finishing details on a project roughly a decade in the making at CERN, the European Organization for Nuclear Research.

The FCC would carry out high-precision experiments in the mid-2040s to study “known physics” in greater detail, then enter a second phase—planned for 2070—that would conduct high-energy collisions of protons and heavy ions that would “open the door to the unknown,” said Giorgio Chiarelli, a research director at Italy’s National Institute of Nuclear Physics.