A U.S. particle physics lab has set a record for achieving the highest man-made temperature, Guinness World Records says.

The Relativistic Heavy Ion Collider at the Brookhaven National Laboratory in New York collides gold ions at nearly the speed of light with impact energy so intense it creates temperatures of around 4 trillion degrees Celsius, about 250,000 times hotter than the center of the sun.

At that temperature and energy level neutrons and protons inside the gold nuclei "melt," researchers said, releasing fundamental quarks and gluons that form a nearly friction-free primordial plasma that existed in Nature only about a millionth of a second after the Big Bang.

"There are many cool things about this ultra-hot matter," physicist Steven Vigdor, said in a Brookhaven release. "We expected to reach these temperatures -- that is, after all, why RHIC was built -- but we did not at all anticipate the nearly perfect liquid behavior."

While the 2.4-mile underground atomic accelerator at RHIC now holds the record, the 17-mile Large Hadron Collider at Europe's CERN laboratory in Switzerland is smashing lead ions together in its own super-hot recreations of the Big Bang and may have already trumped the U.S. research record.

"The energy density at the LHC is a factor of three higher than at RHIC," CERN physicist Despina Hatzifotiadou said. "This translates to a 30 percent increase in absolute temperature compared to the value achieved by RHIC."

However, CERN has not yet published an official temperature measurement of its own quark-gluon plasma, leaving the record in New York -- for now.