The Higgs boson is often described as the God particle because of its fundamental role in understanding the mass of elementary particles. Discovered in 2012, it is at the heart of numerous research projects in physics. Recently, researchers at the Max Planck Institute have made significant advances in measuring its interactions with other particles, which offers exciting prospects for the future of science.
What is the Higgs Boson?
In the standard model of particle physics, the boson de Higgs plays a fundamental role in giving mass to particles. To fully understand how this happens, it is necessary to recall the concepts of field and Higgs mechanism.
Think of the Higgs field as a kind of invisible network or mud that fills all the space in the universe. This field, filled with Higgs bosons, exists everywhere, even in a vacuum. When a particle passes through this field, it interacts with it. The Higgs mechanism essentially explains how this interaction with the field gives mass to particles.
To better understand this, imagine yourself in a swimming pool. If the water is calm, it is easy to swim and move around. But if you're trying to swim in a pool filled with foam or gel, you'll have to put in a lot more effort to move forward. And for good reason, the foam or gel creates a kind of resistance that slows down your movement.
The Higgs field works essentially in a similar way. As a particle moves through this field, it drags in matter, which is comparable to swimming in a pool of foam. This interaction with the Higgs field is what we call mass acquisition. The more strongly a particle interacts with the Higgs field, the more it is slowed down, the more mass it acquires. This mass then allows the particles to combine to create complex structures.
Why measure Higgs Boson Interactions?
To understand how the Higgs boson influences particles, scientists measure its interactions with other particles like quarks, which are components of protons and neutrons. When the Higgs boson decays, it produces what are called particle jets. These jets are like shards that disperse when a stone falls into water. To obtain precise information, researchers must then identify the types of quarks present in these jets, which allows them to better understand the interactions between the Higgs boson and them. It's a bit like having to analyze the pieces of a puzzle to understand how it fits together.
At the recent International Conference on High Energy Physics (ICHEP) 2024, researchers from the Max Planck Institute presented impressive results based on data collected by the Large Hadron Collider (LHC). For these experiments, researchers used improved methods to analyze data from particle collisions.
The discoveries
As part of their work, the researchers observed events that involve the Higgs boson and two other particles called W bosons or Z bosons.
- Boson de Higgs et Boson W : they saw that the Higgs boson combines with a W boson and then decays into particles called bottom quarks. The statistical significance of this observation is 5.3p. This means that researchers are extremely confident that this interaction is real and not due to chance. In other words, there is less than a one in a million chance that this observation is a false positive.
- Boson de Higgs et Boson Z : they also observed that the Higgs boson combines with a Z boson and decays into bottom quarks. This observation has a statistical significance of 4.9p. This also shows high confidence in the results, but a little lower than for the interaction with the W boson. Here, there is about a one in 140,000 chance that this observation is due to chance.
The researchers also sought to observe the decay of the Higgs boson into charm quarks. However, this process is much rarer than bottom quark decays and is therefore still too difficult to detect directly with the available data. The researchers therefore established an upper limit for this type of decay. This means that they set a threshold for how many of these decays would be needed to be detected, and so far they have not been observed in sufficient numbers to confirm their presence.
Why it matters
Regardless, these observations are statistically significant and confirm the theoretical predictions. These new measures are crucial for several reasons. First, they improve our understanding of the interactions of the Higgs boson with quarks by providing more precise data. These results show that the measured interactions are consistent with the predictions of the standard model, confirming the validity of this model so far.
Additionally, these advances have implications for the future of particle physics research. They pave the way for the next phase of the LHC, called HL-LHC (High-Luminosity LHC), which will allow these processes to be explored with even greater precision. The HL-LHC is expected to provide additional data that could help detect even rarer processes and deepen our understanding of the Higgs boson and its role in the universe.
These discoveries on the Higgs boson made by the Max Planck Institute are therefore an important step in particle physics research. By refining measurements of the interactions of the Higgs boson with quarks, researchers are bringing us closer to a more complete understanding of this fundamental particle.
Recent results obtained by researchers at the Max Planck Institute also open up fascinating perspectives for the exploration of physics beyond the Standard Model. Indeed, any deviation from current predictions in the interactions of the Higgs boson could indicate the existence of new particles or fundamental forces as yet unknown. This research is therefore not limited to confirming existing theories, but it could well reveal unexpected phenomena which would revolutionize our understanding of the universe. This is why each new measurement carried out with precision is a further step towards the discovery of potential new horizons in particle physics.
