Ion collider, doomsday fears rev up

P. Weiss

The knob is rattling on a door to the remote past. However, no monster lurks on the other side, say officials at the Relativistic Heavy Ion Collider (RHIC), a $600 million particle accelerator that took its first step toward full operation last month.

On July 16, gold ions began zipping around one of RHIC's two 3.8-kilometer rings at Brookhaven National Laboratory in Upton, N.Y. Rumors were already circulating that the machine, some 8 years in the making, might destroy Earth.

In experiments scheduled to begin in November, nuclei will collide in mighty blasts at six spots around the ring. Researchers expect protons and neutrons in the explosions to dissolve into wads of so-called quark-gluon plasma (SN:9/21/96, p. 190), the primordial stuff from which all atomic nuclei were born in the Big Bang. "We are creating a new state of matter—new, that is, since the Big Bang," says Satoshi Ozaki, RHIC's director.

The lab faces an odd safety question: Will collisions create black holes, starting a chain reaction that eats up Earth?

Each blast is too tiny to make a black hole, Ozaki says. Nevertheless, the lab has convened a panel to address the doomsday scenarios.

As RHIC comes to life, two other large, extraordinary physics tools are also debuting. At the Thomas Jefferson National Accelerator Facility in Newport News, Va., the world's most powerful free electron laser has attained an average power of 1.7 kilowatts—more that 150 times better than its predecessor at Vanderbilt University in Nashville. Both basic researchers and industry scientists are using the unusual laser.

Researchers working at Oak Ridge (Tenn.) National Laboratory have published results for the first time from the Holifield Radioactive Ion Beam Facility. The facility—the first of its kind in the United States and second in the world—accelerates beams of short-lived radioisotopes. In the July 5 Physical Review Letters, scientists describe using a beam of unstable fluorine ions to study an elusive nuclear state of neon critical to understanding stellar explosions called novae.

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References:

Bardayan, D.W., et al. 1999. Observation of the astrophysically important 3⁺ State in ¹⁸Ne via elastic scattering of a radioactive ¹⁷F beam from ¹H. Physical Review Letters 83(July 5):45.

Further Readings:

Mukerjee, M. 1999. A little Big Bang. Scientific American 280(March):60.

Peterson, I. 1997. Proton-go-round. Science News 152(Sept. 6):158.

______. 1996. Microcosmic bang. Science News 150(Sept. 21):190.

For more information on the Relativistic Heavy Ion Collider and quark-gluon plasma, go to http://www.bnl.gov/RHIC/.

Further information about accelerator astrophysics can be found at Physical Review Focus at http://focus.aps.org/story/v4/st2.

Sources:

Satoshi Ozaki
Brookhaven National Laboratory
Relativistic Heavy Ion Collider
Post Office Box 5000
Upton, NY 11973-5000

From Science News, Volume 156, No. 6, August 7, 1999, p. 95.
Copyright ©1999, Science Service.