Mystery began on 19 September 2008 according to the news on 22 September: The Large Hadron Collider (LHC) was shut down last Thursday owing to a fault with its cooling system. Scientists managed to restart it again last Friday, only for it to break down later in the day. Repairs will be carried out on the machine, which will take at least two months. An investigation into technical problems with the world's largest atom-smasher could produce its preliminary findings this week into why it had to be shut down.(1)
The mystery then grew because a tonne of helium had spilled. The project manager, Lyn Evans, "it was a hard blow for us," he said.(2) A connector between electromagnets failed and heated up, causing a magnet quench. Furthermore, Evans guessed that the fault was probably a poor soldering job on one of the 10,000 connections.
My interest took a leap because Evans would tell us it was one soldering fault out of 10,000 connections without any visual inspection. The location where this fault occurred, Sector 3-4, is still too dangerous to enter while it warms up to room temperature.
This guess of a failure, without visual inspection, in one soldering spot suggested to me high confidence in instrumentation and high confidence in the measured data. I then marveled at this "alleged" precision.
As we wait for the accident events to be described in the coming months, I keep thinking of 'the bridge that repaired itself after an explosion' that I watched in the Universal Film Studios. This hot-spot problem seems to beg a creative solution. I ask now: Can the LHC be made to fix itself on its own when a fault like this happens again? Why not? Come on.
LHC documentation reads: Based on CERN operation and sub-systems commissioning experiences, the expected overall availability of the LHC cryogenic system should reach approximately 98 per cent once the first commissioning with beam is completed.(3) What has happened to this level of confidence? How does the hot-spot problem change this percentage?
It turns out there are 12 tonnes of helium in each sector. I don't know the exact sequence of events that led to the quench; but have they recovered the spilled helium for recycling because it is a nonrenewable resource? Was the level 3 alarm activated when the quench occurred?
The LHC, in my judgment, is the most complicated and the largest and the most advanced engineering project in history. I am still ruminating over the manner the Large Hadron Collider was shutdown and became, sadly, a large helium cooler. I can hardly wait for some LHC accident report to bring light to this mystery.