Mechanisms of the Higgs Boson Decay

Mechanisms of the Higgs boson decay has been researched by scientists from Samara University. In their opinion, the information obtained will contribute to New Physics and help more accurately predict experimental data of modern colliders. The research results are published in the journal Physics of Particles and Nuclei.

The Higgs boson is an elementary particle, a quantum of the Higgs field, which, according to the Standard Model of Particle Physics, is responsible for other elementary particles gaining mass. The boson was discovered in 2012, at the Large Hadron Collider (LHC), as a result of experiments that have been “hunting” for it for over 40 years. It has been one of the most important discoveries of the 21st century, completing the Standard Model.

The Higgs boson discovery gave rise to detailed studies of its properties and decay features and generated new research areas for searching for physics beyond the Standard Model, including dark-matter particles.

The Higgs boson results from colliding protons at the Large Hadron Collider (LHC). It lives for fractions of a second and decays into other particles, which can be detected by detectors. Scientists analyze traces of these decays, in order to confirm the boson existence and study its properties, for example, by the ATLAS and CMS experiments.

Scientists from Samara University have studied generating bound states of heavy quarks and leptons in the Higgs boson decay and explored the basic decay mechanisms. Fedor Martynenko, Assistant of the Department of General and Theoretical Physics at Samara University, noted that the research was conducted by applying theoretical methods.

“We used the apparatus of quantum field theory, for calculating the probabilities (decay widths) of rare processes, in which the Higgs boson decays not into free particles, but into bound systems – quarkonia (for example, charmonia and Bc mesons) and leptonia (for example, pairs of muons). These calculations allow predicting the probability of such processes, for the purpose of subsequently analyzing experimental data obtained from modern accelerators”, he said.

According to him, researching these exotic decay channels is extremely important for several reasons. Firstly, it will help increase the accuracy of measurements of the force of interacting the Higgs boson with heavy elementary particles, since decays into bound states serve as a highly precise tool for such measurements.

“Secondly, the research will contribute to the search for New Physics. Any variances of the predicted values from the experimentally measured ones may indicate the existence of physics beyond the Standard Model, for example, the presence of new particles or interactions that have not been discovered yet”, explained Fedor Martynenko.

In the scientists’ opinion, the theoretical predictions obtained lay the groundwork for researching by using the next generation of colliders. High-order statistics and accuracy expected from the Large Hadron Collider after its modernization (HL-LHC) will allow starting to search for these rare processes. However, their most complete verification and detailed study will be possible at future electron-positron “Higgs factories”, such as the FCC (Future Circular Collider), ILC, CLIC and CEPC. It is these facilities, where Higgs bosons will be generated in large numbers, that scientists will be able to detect similar “rare” processes at.

Source: ria.ru