In 2012, the Large Hadron Collider (LHC) at CERN made the significant discovery of the Higgs boson, which marked a significant development in particle physics. From that point forward, the Map Book and CMS joint efforts have been perseveringly researching the properties of this novel molecule and looking to lay out the various manners by which it is created and rots into different particles.
At this week’s Large Hadron Collider Physics (LHCP) conference, ATLAS and CMS will talk about how they worked together to find the first evidence of the rare decay of the Higgs boson into a Z boson, an electrically neutral carrier of the weak force, and a photon, an electromagnetic force carrier. This Higgs boson rot could give aberrant proof of the presence of particles beyond those anticipated by the Standard Model of molecular physical science.
The rot of the Higgs boson into a Z boson and a photon is like the rot of two photons. The Higgs boson does not directly decompose into these pairs of particles during these processes. Instead, a “loop” of “virtual” particles that pop in and out of existence and cannot be directly detected guides the decay. These virtual particles might include brand-new particles that interact with the Higgs boson but have not yet been discovered.
“Each particle has a unique relationship with the Higgs boson, making the hunt for uncommon Higgs decays a top goal. By meticulously combining the individual data of ATLAS and CMS, we have taken a step closer to solving yet another mystery involving the Higgs boson.”
ATLAS physics coordinator Pamela Ferrari
If the Higgs boson has a mass of about 125 billion electronvolts, the Standard Model predicts that about 0.15 percent of the Higgs bosons will decay into a Z boson and a photon. However, a different decay rate is predicted by some theories that go beyond the Standard Model. Therefore, measuring the decay rate provides useful insights into the Higgs boson’s nature and physics beyond the Standard Model.
Previously, ATLAS and CMS independently conducted extensive searches for the Higgs boson’s decay into a Z boson and a photon using data from proton-proton collisions at the LHC. Both ventures utilized comparable systems, distinguishing the Z boson through its rots into sets of electrons or muons — heavier forms of electrons. These Z-boson rots happen in around 6.6% of the cases.
In these ventures, crash occasions related to this Higgs boson rot (the sign) would be recognized as a limited top over a smooth foundation of occasions in the circulation of the joined mass of the rot items. ATLAS and CMS classified events according to the characteristics of the most common modes in which the Higgs boson is produced in order to increase the decay’s sensitivity. In addition, they differentiated between signal and background events using cutting-edge machine learning methods.
In another review, Map Book and CMS have now combined efforts to amplify the result of their pursuit. The collaborations have significantly increased the statistical precision and scope of their searches by combining the data sets collected by both experiments during the second run of the LHC, which took place between 2015 and 2018.
This cooperative exertion brought about the principal proof of the Higgs boson’s rot into a Z boson and a photon. The statistical significance of the result is 3.4 standard deviations, which is lower than the usual requirement of 5 standard deviations to declare an observation. The measured signal rate is 1.9 standard deviations higher than the prediction made by the standard model.
According to Pamela Ferrari, ATLAS physics coordinator, “each particle has a special relationship with the Higgs boson, making the search for rare Higgs decays a high priority.” We have made progress toward solving yet another Higgs boson mystery by meticulously combining the individual ATLAS and CMS results.”
“The presence of new particles could significantly affect uncommon Higgs rot modes,” says CMS material science facilitator Florencia Canelli. “The Standard Model is put to the test with vigor in this study. We will be able to improve the precision of this test and investigate ever rarer Higgs decays with the ongoing third run of the LHC and the upcoming High-Luminosity LHC.”
Provided by CERN
