On a roller coaster
Alumnus: Stephen Myers
At CERN since 1972, CERN Director of Accelerators and Technology from 2009 to 2013
Today: Executive Chair ADAM SA
On a rollercoaster. This must have been Steve Myers’s feelings around the 10th September 2008. While the whole CERN community was celebrating the first beam in the LHC, Steve was about to be nominated CERN Director of Accelerators and Technology. However, only 15 hours after being nominated by the CERN Council, an incident happened in the LHC and the celebration was (temporarily) over. “We went from feeling really elated to feeling completely depressed and demotivated 10 days later,” he describes. “Being Director of Accelerators at that time was no gift. It was a tough job. We had to find what went wrong, do the repair and make sure that it would never happen again. That period, from September to Christmas time was a very hectic period for everybody at CERN.”
However bad it was, having to deal with the consequences of the incident, it’s the emotion of the LHC start-up that still first comes to Steve’s mind. “On 10th September I was here, in the CCC, together with many other people,” he recalls. “This place was packed with journalists. We passed the beam through, one octant at a time, and each time it passed through the octant there was a huge cheer, and people were jumping up and down. Then we finally made it through a full turn of the 27km. Soon after, we managed to circulate the beam for many turns. Having worked on the LHC for many years, the 10th September was the real test to confirm the success of our endeavours. Normally you would never dare to say that we were going to circulate a beam on a given day. In this case, due to the huge media attention, we were obliged to specify a given date for the first circulation. We knew we had done everything possible for success, but you don’t know what lies ahead when you have 27 km packed with high-tech equipment: if any component does not function properly the beam will not go around. That day, when we started, we worried “this is going to take a lot of time and all these journalists are here and what are we going to do if it doesn’t go around”. Amazingly, we went straight through the first octant; all the diagnostics worked, the control systems worked, everything had been incredibly well prepared. And then we went through the second octant and the third etc. and then made a full turn. And each time the beam made its way through an octant – more than three km – everybody in the control room, including the journalists were cheering and then when the beam made a complete turn, people were launching hats up in the air. It was a fantastic day, probably the most exciting of all the times I have been working at CERN.”
Ten days later, Steve was working on organizing the “Chamonix” meeting which would have prepared beam operation of the machine. “I had a call from the head of the vacuum group saying: 27 km are at atmospheric pressure. When you get news like that, you know it’s serious. And then we found that there had been a major incident, which later, following detailed investigations, was identified as the result of a poor-quality soldering in a magnet interconnect. It is important to point out that the LHC is the first machine which has the capability to cause huge damage to its own high-tech equipment. The incident on September 18, caused damage over a range of 600 metres in the tunnel. We had lost a total of 53 magnets.”
The focus of the whole laboratory rapidly changed to recover from this unthinkably terrible situation. Many years of funding and hard work were at stake. “We had to concentrate on repairing the machine and making sure that a similar accident could not happen again,” says Steve. “But when we studied the fault tree of the incident, and prepared for the repair, we realized that there was another more complicated accident that could happen. There was not time to make this second repair so we could not undertake both repairs as it would have taken at least two years. So, we had to decide to make the repair of the damage done, upgrade the magnet protection system and propose operation at an energy lower than the design energy of the LHC. And this was really an extremely difficult decision to take. There were people on one side saying “you should go to 5 TeV at least”; and there were others including myself, insisting that “the maximum beam energy should be limited to 3.5 TeV because of the risk of provoking another major incident. On the one hand we did not want to risk damaging the LHC again: this could have been the end of CERN, and on the other hand we needed high energy and integrated luminosity to find the Higgs boson. A very tough decision. Following long, difficult discussions I succeeded in getting the decision to operate at 3.5TeV per beam for the first years of operation.”
Luckily the decision proved to be the right one; not only was the LHC in a perfectly safe operational mode but the Higgs Boson was discovered in 2012, less than three years after the first collisions. In 2013, it was time for Steve to retire but not before taking on another new initiative. In his words: “When my 5-year mandate as director finished, the Director General asked me to set up a new office called CERN Medical Applications. I think that everybody at CERN knew that I was very interested in developing technologies to be applied in medicine. So, I re-focused myself and directed the setting up of seven new medical initiatives in that capacity. Following the mandated two years term of office, I decided to step down and go into retirement. Then, unexpectedly, I was offered an opportunity to head up the design and development of a proton linear accelerator for cancer therapy. A CERN spin-off company was building this system. I was very enthusiastic about taking this new challenge because I knew we would be treating cancer patients with this machine. I started in this new position outside CERN, at the beginning of 2016 and I am still continuing. We are hoping to be treating the first patients in 2020.”
Today, as head of the Linac project in this company, Steve can use the knowledge and know-how obtained at CERN in the field of accelerator physics and apply it for the benefit of medicine. “When I looked at the private sector, I realized that most of the companies that were developing equipment for cancer therapy were using old-fashioned cyclotrons,” he says. “Today, there is not a single cyclotron operating at CERN, and there hasn’t been for 30 years because they are old-fashioned machines. So, one of the first things I did was to study the accelerator requirements needed for treating cancer. Then I matched these requirements with the inherent characteristics of existing types of accelerators. I came very quickly to the conclusion that Linacs are the best type of accelerator for cancer therapy. The main reason for this is that, to treat a tumour you need to change the beam energy (which changes the depth at which the radiation is deposited): if the tumour is very deep you need high energy and if the tumour is superficial you need lower energy. Most tumours cover a volume and usually you start radiation at the back of the target and come to the front. This means you must change the beam energy. Cyclotrons are fixed-energy machines, so in order to reduce the beam energy, an absorber is placed in the path of the beam. But the absorber can produce losses up to 99% of the proton beam depending on the amount of energy reduction needed. In addition, because the absorber is a mechanical device, it can’t be moved very rapidly. Whereas with a Linac you can change the beam energy 200-300 times per second. With a mechanical device, once-twice per second is current. This has a big impact on how you treat patients.”
Changing from CERN to a private company is not straightforward even if the career change happens after retirement. “At CERN all the multiple expertise needed to develop accelerators are already in house. In a small company the range of expertise is much more limited. However, on the positive side, it is much easier and faster to recruit people in a small company due to the reduced administration.”
Today Steve is a proud CERN Alumnus. As a Director he had dreamt of having a CERN Alumni Programme and now that this has become reality, he is one of the most convinced ambassadors of the initiative and, needless to say, of CERN. “CERN is a fantastic brand,” he confirms. “When you tell people that you have worked at CERN they are usually very interested, impressed and enthusiastic. I am proud to be a CERN Alumnus, CERN is a fantastic organization, and in my opinion, the world’s best international organization.”
This is thanks to you too, Steve.
Watch the video of the interview!