July 4, 2012

experts anticipate Higgs news from CERN

The first of two rapid reaction sent out from the SMC, comments from leading particle physicists were sent out in anticipation of the announcement that confirmed the Higgs boson had been discovered at the LHC.

Prof Tom Kibble, Emeritus Professor of Theoretical Physics and Senior Research Fellow at Imperial College London, said:

“It is very exciting to find that work I was involved in nearly fifty years ago is once more at the centre of attention. At the time, the Higgs boson did not seem a very significant feature of the theory, but it has become so as the last missing piece of the ‘standard model’. Its discovery will complete a chapter, but not the story — the model is amazingly successful, but many features remain to be explained.”

Prof Dan Tovey, Professor of Particle Physics at the University of Sheffield and leads the Sheffield team working on the ATLAS, said:

“The preliminary results shown today by the ATLAS collaboration are the product of over twenty years of work by physicists and engineers in the UK, from across Europe and throughout the world.

“UK scientists and engineers designed and built many of the components of the experiment, including much of the apparatus that tracks particles produced in LHC collisions inside ATLAS and much of the electronics and software which allows the experiment to identify whether an interesting collision worthy of later scrutiny has occurred. UK physicists also wrote much of the software used to analyse and interpret the data. Computing facilities in the UK played a major role in processing the data. All these components were crucial for the preliminary results shown today.

“The ATLAS experiment was designed to answer the question of how the fundamental particles of nature acquire their masses – via the Higgs boson or in some other way. Today marks a crucial point on that journey.

“In addition to the hunt for the Higgs boson searches are continuing for evidence of particles predicted by the new theories extending the Standard Model. These may lead in the next few years to observation of such exotic new phenomena as dark matter, magnetic monopoles, or even extra dimensions of space. The excitement among particle physicists is palpable.”

Dr Antonella De Santo, Reader in Experimental Particle Physics, University of Sussex, said:

“These are very exciting times to be a physicist, and today we are beginning to harvest the fruits of years of hard work and perseverance of many talented people. The Large Hadron Collider is a ‘once-in-a-lifetime’ opportunity to do great science and I feel very proud and privileged to be part of it.”

Dr Joel Goldstein, leader of the CMS activity in Bristol, said:

“If the Higgs has been finally identified, this will be the biggest particle physics discovery for forty years.”

Questions, answered by Stefan Söldner-Rembold (SS) at the University of Manchester, and Joel Goldstein (JG), leader of the CMS activity in Bristol: Q. I understand that it is the Higgs field that confers mass but what is the relationship of the Higgs boson to the field? And if it is the field that confers mass, what does the Higgs boson do? SS: “In quantum theory all fields have “quanta” associated with them. As an example, the photon is the quantum of the electromagnetic field. In analogy, the Higgs boson is the particle related to the Higgs field.” JG: “The Higgs field permeates throughout the whole universe. A Higgs boson can be thought of as a little ripple of the Higgs field. It is the smallest ripple allowed by quantum mechanics.” Q. I understand that the field is around us all the time. Are Higgs bosons there too? I.e. are they being made in nature all the time or were they only made in the fraction of the second after the Big Bang, hence the need to recreate these conditions? SS: “Higgs particles are very heavy and it therefore requires a lot of energy to produce them. This is the reason we need high-energy accelerators like the LHC.” JG: “It takes a lot of energy to create real Higgs bosons. Also they are very short lived and decay rapidly into other particles. It is this process that is being observed at LHC.” Q. If the field is there all the time, why not just look for it? Or is it even harder to detect? SS: “The Higgs field interacts with the fundamental particles that make up the world around us and it gives them their mass. When measuring particle masses we see the Higgs field at work. However, to get a positive proof that this theory is really correct we need to find the Higgs particle which comes with the field. Peter Higgs actually postulated the existence of the Higgs particle as an afterthought to his original paper as a possible experimental signature of his theory.” JG: “The Higgs field provides a mechanism to generate mass in various elementary particles. In particular, the fact that the W-bosons and the Z-bosons have mass is good indirect evidence for the Higgs field. Detecting the Higgs boson will provide a direct test for the existence of the Higgs field itself.”