August 2010

Promised Fireballs

Everybody agreed that the Large Hadron Collider was the last stand in the hunt for the Higgs boson. Circling for 17 miles underneath the complex of aging postwar buildings outside Geneva (and out into France) that constitute the European Organization for Nuclear Research, or CERN, the collider was designed to accelerate the subatomic particles known as protons to more than 99 percent of the speed of light — an energy of seven trillion electron volts — and crash them together.

The resulting tiny fireballs would recreate temperatures and densities that prevailed when the universe was only a trillionth of a second old. This was unexplored territory, and anything could happen, including — about once in every four billion collisions, according to theoretical calculations — a Higgs boson. To record it all, the two teams erected detectors, mountains of wire and computers, on opposite sides of the underground ring to capture the collisions.

“Either we find the Higgs boson, or some stranger phenomenon must happen,” said Fabiola Gianotti, a CERN scientist who led one of the groups, named Atlas. Their rival was called CMS. Both were named after their gigantic detectors. (Two other detectors, named Alice and LHCb, were built to investigate more specialized physics at the collider.)

The collider, 15 years and $10 billion in the making, was first turned on in September 2008. Then, just a week later, a section of it blew up when some electrical circuits proved unable to handle the currents needed for the giant superconducting magnets that steered the protons. Repairs took a year and a half; in March 2010, the collider started up again at half power to avoid stressing the circuits.

When I visited in August 2010, Dr. Gianotti’s desk on the fourth floor of a new building a stone’s throw from the main CERN cafeteria was as sleek and uncluttered as an aircraft’s wing, the few papers on it arranged with geometrical precision. A slender woman with dancing eyes, Dr. Gianotti gave the impression of being as graceful and strong as piano wire. She needed all of that.

As the spokeswoman for the Atlas collaboration, Dr. Gianotti, then 46, was the nominal herder of 3,000 putative Einsteins, the orchestrator of a hive mind of brilliance — responsible for getting all the trains to run on time; for all the calibrations and simulations to match; for all the physicists, from the computer analysts who massaged the final data to anyone who ever wielded a screwdriver in the detector cavern, to sign off on the results from those fireball collisions.

That made Dr. Gianotti the most visible woman in high-energy physics, a field notoriously laden with testosterone. Journalists always asked about that, but it was no big deal, she said, adding that a quarter of the Atlas collaborators are women — so many that on occasion she had gone out and recruited men to attend management meetings.