On the night of July 3, 2012, many North American Electrical Engineers went without sleep. They were tuned in to a webcast from the historic town of Geneva Switzerland. There, at a press conference, a long-anticipated announcement was made. The Higgs Boson had been discovered, culminating in a quest that had gone on for some 50 years.
The Quest for the Higgs Boson
This development resulted in a Nobel Prize, yet it faced many difficulties along the way, most of them technical in origin, and all involving engineers as well as scientists. The existence of the Higgs had been postulated by theorists as the missing piece of a jigsaw puzzle called the Standard Model which was to explain the sub-atomic frontier. The Higgs in particular is thought to confer the fundamental property of mass.
A good place to start the saga is in the 1970s on Eastern Long Island, where a new 'atom smashing' particle accelerator called Isabelle was to be built to lead the Higgs chase. An engineering prototype of the critical superconducting magnets was built, tested and met specs. On the strength of this, the massive construction project went forward.
The problem was, none of the subsequent production magnets met those same performance parameters. Months later, when the engineers and physicists were able to duplicate the original, Isabelle was late, over budget, and in political trouble. It was then cancelled by Congress and the existing excavation was repurposed. The quest was stalled.
The scene eventually shifted to the little town of Waxahatchee Texas, where a new, larger accelerator was to be built. But a similar story was played out, technical problems, delays, overruns, and cancellation. At this point the US government concluded that it had put enough holes in the ground and it stepped back from further billion-dollar efforts of its own.
Enter CERN, a French acronym for the European Organization for Nuclear Research, a multi-nation consortium in Geneva also looking for the Higgs. Their Large Hadron Collider (LHC) device was completed in the early days of the new century.
And guess what? During its commissioning run, it failed, and in rather spectacular fashion, with an explosion at one of the magnets. Again scientists and engineers were brought in to solve the problem, delays were inevitable and expenses soared. But this time, the powers-that-be mustered sufficient support to see it through, at least at half its design power, but still hopefully sufficient to find the Higgs if there was a Higgs to find.
The Operating Facility
It might be helpful at this point to mention of scale of the apparatus. The accelerator ring resides in a tunnel some 27 kilometers in circumference; thus it doesn't quite fit in its Geneva site and so it co-resides in neighboring France. The LHC represents a collaborative effort of people from over 100 nations, some of which do not even recognize each other in the diplomatic arena.
The LHC operates by accelerating and colliding two opposing particle beams of hadrons (such as protons) at energies of 7 Tera-electron volts. The collisions produce a soup of sub-atomic particles that must be measured and characterized on-the-fly within seconds to separate the interactions of interest from the noise and discern the physics that has taken place.
There are two main detectors on the ring, but these detectors are not your grandfather's Geiger counter. Each one stands several stories tall and is jam packed with sensitive micro-electronics, tons of magnets and walls of computers. When in operation, the particle collisions that it makes generate dozens of petabytes per year, stored, analyzed and filtered by 140 additional dedicated massive computing centers in 35 countries. The two detectors, known as ATLAS and CMS, are each massive enterprises in their own right, involving thousands of scientists, post-docs, graduate students and craftspeople. In order to make a discovery, each of the two detector groups must substantially agree on what has taken place. And that is what finally happened by July of 2012.
The CERN site showing the LHC ring, the Atlas and CMS detectors and several others.
Initial Results
Since the announcement in 2012, the discovery of the Higgs has been confirmed with increasing certainty and accuracy. The facility has produced other interesting physics as well. But just as valuable may be the engineering lessons learned.
The false starts in New York and Texas, and the early explosion in Geneva were at the core engineering problems. They arose for two basic reasons, 1) because they extended the reach of technology (which was appropriate) and 2) they often suffered from lack of good engineering practice (which was not).
Many engineering tasks were taken on by students and post-docs who were savvy, available and inexpensive, but many were not trained in the engineering discipline that mandates such niceties as testing, documentation, and safety considerations. Ultimately, this frugality and haste reaped the usual consequences, but at this scale of work, the consequences carried worldwide significance.
All this is important because the story is far from over. The Higgs did not turn out to be exactly what and where the theory predicted, so both the model and the experimentation must be revisited. The LHC is still operating at only half its ultimate energy, as this time the designers are exercising due caution.
There are also other mysteries of the cosmos to be explored by the LHC and future apparatus, among them dark matter and energy. Anyone who has ever peeled an onion will recognize that some jobs are never quite done, and the physical world turns out to be quite an onion indeed.