A discovery that could lead to new subatomic particle

A discovery that could lead to new subatomic particle

An important contribution to the analysis on the decay of beauty mesons made by physicists from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) from Poland, might lead to the dawn of a new era, that of 'new physics'.

There are some indications that physicists working at the LHC accelerator at the European Organization for Nuclear Research (CERN) near Geneva may see the first traces of physics beyond the current theory, which describes the structure of matter.

This indication emerges from the latest analysis of data collected by the LHCb experiment in 2011 and 2012. Physicists from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Krak w, Poland, have made important contribution to the analysis.

To put it in terms of the cinema, where we once only had a few leaked scenes from an much-anticipated blockbuster, the LHC has finally treated fans to the first real trailer, says Prof. Mariusz Witek.

To describe the structure of matter on the scale of elementary particles we use the Standard Model, a theoretical framework formulated in the 1970s. Particles we now consider as elementary play various roles. Bosons are carriers of forces: photons are related to electromagnetic interactions, eight types of gluons are responsible for strong interactions, and W+, W- and Z0 bosons mediate weak interactions.

Matter is formed by particles called fermions, which are divided into quarks and leptons. In the Standard Model, there are six types of quarks (down, up, strange, charm, top and bottom) and six types of leptons (electrons, muons, taons and their three corresponding neutrinos) as well as 12 antiparticles associated with them. The recently discovered Higgs boson provides particles with mass.

Aattention is being paid to detecting new elementary particles beyond the Standard Model. The ATLAS and CMS experiments are trying to see such particles directly. However, it cannot be ruled out that the mass of the new particles is just too high to be produced at the energies of the LHC accelerator.

In 2011, shortly after gathering the first large samples by the LHCb experiment, a puzzling anomaly regarding the beauty meson was noticed and announced on public site of LHCb.

An anomaly was observed in the decay of a B meson containing two muons among its products.

Dr. Marcin Chrzaszcz from IFJ PAN, one of the main authors of the analysis, proposed an alternative method in which each parameter was determined independently of the others.

My approach can be likened to determining the year when a family portrait was taken. Rather than looking at the whole picture, it is better to analyze each person individually and from that perspective try to work out the year the portrait was taken, explains Dr. Chrzaszcz.

The LHC has recently began another round of colliding protons at higher energy levels, by the end of which physicists will have at their disposal another batch of data to analyze. Will the new physics then become a reality

As Prof. Witek sums it up: Just like it is with a good movie: everybody wonders what's going to happen in the end, and nobody wants to wait for it.

A discovery that could lead to new subatomic particle