Hayadan > CERN Tour Notes Chapter 6: In Search of the Tau Particle

CERN Tour Notes Chapter 6: In Search of the Tau Particle

Dr. Noam Tal Hod, formerly of Tel Aviv University and currently a post-doctoral student at the NIKHEF Institute in the Netherlands, moved to design experiments to find new physics in particles created at the lowest energies that can be found in an accelerator.

Dr. Noam Tal Hood, post-doctoral student at the NIKHEF Institute. Photo: Avi Blizovsky

Dr. Noam Tal Hood compares the search for particles that will confirm the existence of new physics, precisely at the low end of the energy spectrum, as a Sisyphean task, but it has a payoff. Dr. Tal Hood did his doctoral research at Tel Aviv University under the guidance of Prof. Erez Etzion. He is currently a post-doctoral researcher at the Dutch research institute NIKHEF which unites several universities in the Netherlands in the field of high energies and is of course stationed at CERN. "In my PhD, I looked for additional dimensions at the highest energies that can be reached experimentally, and now I work at the other end of the spectrum - on the lowest energies."

"I am responsible for a trigger: a component that decides which of the events we receive in the detector will be saved on the disk. This is the most important step because if it is not planned correctly, we may miss interesting phenomena. However, we don't always know in advance what is interesting and what is not, and in every run of the accelerator an interesting phenomenon may be revealed, so we need to be creative and think generically about what to keep."

"We previously looked for evidence of the existence of a new particle that is discovered mainly at high energies through its decay into known products. I am looking for the tau particle - the heaviest brother of the electron. We have known it for many years and many of its properties have been measured, but I am looking for an exotic form in which this particle - the heavy brother of the electron, is twice as heavy as the proton."

"The Standard Model does not constrain us in the form of decay of the tau particle, this means that we can look for exotic decays of it, but so far we have not seen evidence of such decay. If it does happen it will be an earthquake in everything related to the standard model. The model does not provide us with information about dark matter, the asymmetry between matter and antimatter and gravity. We do not know how to explain gravitational interactions between particles the way we explain electromagnetic or nuclear interactions. If we see a particle that we know decay in a way that the Standard Model does not, it means that there must be new physics. Such a discovery will open the door to a new field of research. After discovering the Higgs we don't stop there. We are going to build an accelerator that will make it possible to produce many Higgs particles and measure them."
What effect will the discovery of additional dimensions have for example?
"It will have an impact on everyone in the world. If we discover, for example, that we have evidence of the existence of additional dimensions, this means that philosophically every person will have to understand what it means to live not in a three-dimensional world with the addition of a time dimension, but in a world of five dimensions or 11. Of course, this will not affect everyday life, but you can think about space travel And on time."

How would it be possible to take shortcuts in space?

Imagine an ant walking on a two-dimensional floor in a straight line. She runs into the wall, makes a 90 degree turn and is currently on a two-dimensional plane again, and again this happens when the ant continues to the ceiling. Suddenly gravity overcomes her and she falls back to the starting point on the floor through the third dimension - the height dimension she does not know in her two dimensional world. If we can enter those dimensions we can reach other places in the universe in zero time. At least if we are particles, as for large bodies like humans, it probably won't be practical even then..."

According to Dr. Tal Hood, besides the experimenters, there are also theoretical physicists at CERN who join for short periods to analyze the data. However, at CERN there is a separation between theorists and experimenters: "I am not allowed to show the material that comes out of the detector to the theorist until an article is published, unless he is one of the people joining the specific analysis. In this field there is a very strong field security. Because many times we see phenomena that seem wrong to us, after a few months we realize that there was a mistake in the process, or some kind of problem in the detector that needs to be fixed, as happened with the neutrons that move faster than the speed of light."

And not only the ant in Dr. Tal Hood's description climbs walls: "My field is exciting, in Sarn in general, and Atlas in particular. just fun It is very Sisyphean and very difficult. You have to climb over walls you encounter every day."

At the end of the doctorate period, Dr. Tal Hood expects to return to Israel, in particular to Tel Aviv University, but it is still difficult to live with the family in a foreign country."

Topic on the science website