‘The announcement was a rather surreal moment’
On 4 July 2012, I was at Nikhef. Together with many colleagues and press, I followed the live-stream of the CERN meeting from the auditorium in Geneva. The announcement was a rather surreal moment. The discovery of the Higgs particle was so grand, both because of its scientific significance and because of the amount of work that went into it. It felt very surreal that suddenly it was all over. It was only a few days later that I felt proud that we had discovered the Higgs particle. You only experience something like that once in your life.
My involvement in the Higgs hunt began five years earlier. During my time in America I had developed a toolkit, software with which you can combine very different data sets and models. Crucial. Our ‘RooFit’ toolkit is used everywhere, at ATLAS and CMS. I was also involved in the search for the decay of the Higgs particle into two W particles, one of the three important decay channels. The most difficult one, though. My PhD student Stefan Gadatsch and I worked together on our analyses. It was time-consuming and it narrowly missed the ATLAS presentation, even though we had pulled an all-nighter on it. The result was, however, in the paper published a month later. The extra W channel made the discovery even stronger statistically.
I often realize how wonderful the found Higgs particle is for experimental physics. At the mass found there is a lot to measure in terms of properties, so there is plenty of work for our group of twenty staff members and PhD students.
The most important question I want to ask the Higgs particle? Whether it has anything to do with cosmic inflation, just after the Big Bang. We really don’t know. We don’t know at all how Mother Nature solved the problems of the Standard Model. Is there a second kind of Higgs particle, for example? I do hope for that sometimes.’
This interview was originally published in Nikhef magazine DIMENSIES #7