Top quarks and fundamental physics at 100 zeptometer
Vidi grant for Ivo van Vulpen
Ivo van Vulpen's Vidi proposal for research on 'Top quarks and fundamental physics at 100 zeptometer' has been granted by NWO. He will study the production of top quarks at the Large Hadron Collider, now under construction at CERN, Geneva. Starting operation in 2007, the higher energies of the colliding protons will allow researchers to look at smaller scales than ever before (several hunderd zeptometers) and hopefully discover and study new physics. Studying top quarks is essential, as their production looks like the new expected physics phenomena that the detectors might reveal at these scales. A better understanding of their behaviour helps to distinguish known and unknown physics.
Research
A fruitful collaboration between experimental and theoretical efforts over the last decades has led to the development of the "Standard Model" (SM) of particle physics. The model combines the 3 quantum forces of nature, the electromagnetic, the weak and the strong force and has been very successful in describing the interactions of elementary particles up to the highest energies available today.
Given the success of the SM it might come as a surprise that most particle physicists believe that the SM cannot be the full story. This model has some fundamental limitations and is unable to answer several fundamental questions in physics today.
The model loses its predictive power when describing physics at distances below 10-19 m. Several models claim to solve the existing problems using a more fundamental description of nature, thereby predicting an unprecedented variety of (sometimes very spectacular) new phenomena. They all introduce new particles or interactions that can be observed by studying physics at distances smaller than 10-19 m.
Large Hadron Collider
The Large Hadron Collider (LHC), a proton-proton collider currently under construction at the European Centre for Particle Physics (CERN), located near Geneva, Switzerland is scheduled to start colliding high energetic protons in 2007. With a centre-of-mass energy of 14 TeV its energy is almost an order of magnitude larger than that of any existing accelerator today, which allows routine exploration of physics at these short distances scales.
Top Quark
The top quark has a special place among the constituents of matter. It is by far the heaviest elementary particle (its mass is equivalent to that of a gold atom) and is expected to play a special role in many extensions of the SM. At the LHC millions of top quarks will be produced which allows to study its properties in great detail. More interesting however is that from an experimental point of view, the well predicted, complex event topology from top quark decays is very similar to that predicted by new physics phenomena. Studying the production of top quarks therefore provides a unique opportunity to understand the detector early during LHC operation, discover the first signs of the breakdown of our current understanding of particle interactions .... and see the first glimpse of the fundamental physics that takes over.
If new particles, spatial dimensions or symmetries exist, we have an excellent opportunity to observe them soon after the startup of the LHC.