{"id":26351,"date":"2025-05-19T16:59:49","date_gmt":"2025-05-19T11:14:49","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=26351"},"modified":"2025-05-19T17:02:15","modified_gmt":"2025-05-19T11:17:15","slug":"ai-enhances-higgs-bosons-charm","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/ai-enhances-higgs-bosons-charm\/","title":{"rendered":"AI enhances Higgs boson\u2019s charm"},"content":{"rendered":"\n

The CMS collaboration presents a new search for the decay of a Higgs boson into charm quarks, bringing physicists closer to unravelling how this unique particle endows matter with mass<\/strong><\/em><\/p>\n\n\n\n

\"\"
Picture of CMS experiment \/\u00a0Photographie de l\u2019exp\u00e9rience CMS\u00a0(Image: CERN)<\/sup><\/em><\/figcaption><\/figure>\n\n\n\n

The\u00a0Higgs boson<\/a>, discovered at the Large Hadron Collider (LHC<\/a>)\u00a0in 2012, plays a central role in the\u00a0Standard Model<\/a>\u00a0of particle physics, endowing elementary particles such as quarks with mass through its interactions. The Higgs boson\u2019s interaction with the heaviest\u00a0\u201cthird-generation\u201d\u00a0quarks\u2014top and bottom quarks\u2014has been\u00a0observed<\/a>\u00a0and found to be in line with the Standard Model. <\/p>\n\n\n\n

But probing its interactions with lighter \u201csecond-generation\u201d quarks, such as the charm quark, and the lightest \u201cfirst-generation\u201d quarks\u2014the up and down quarks that make up the building blocks of atomic nuclei\u2014remains a formidable challenge, leaving unanswered the question of whether or not the Higgs boson is responsible for generating the masses of the quarks that make up ordinary matter.<\/p>\n\n\n\n

Researchers study the Higgs boson’s interactions by looking at how the particle decays into\u2014or is produced with\u2014other particles in high-energy proton\u2013proton collisions at the LHC. At a\u00a0seminar<\/a>\u00a0held at CERN last\u00a0week, the\u00a0CMS<\/a>\u00a0experiment collaboration reported the results of the first\u00a0search<\/a>\u00a0for a Higgs boson decaying into a pair of charm quarks in collision events where the Higgs boson is produced alongside two top quarks. Exploiting cutting-edge AI techniques, this novel search has been used to set the most stringent limits to date on the interaction between the Higgs boson and the charm quark.<\/p>\n\n\n\n

The production of a Higgs boson in association with a top-quark pair, with the Higgs boson decaying into pairs of quarks, is not only a rare process at the LHC but also a particularly challenging one to distinguish from similar-looking background collision events. <\/p>\n\n\n\n

That\u2019s because quarks immediately produce collimated sprays (or \u201cjets\u201d) of hadrons that travel only a small distance before decaying, making it especially difficult to identify\u00a0jets originating from charm quarks that are created in\u00a0the decay of a Higgs boson from jets\u00a0originating from other types of quarks. Traditional identification methods, referred to as \u201ctagging,\u201d struggle to efficiently recognize charm jets, necessitating the development of more advanced discrimination techniques.<\/p>\n\n\n\n

\u201cThis search required a paradigm shift in analysis techniques,\u201d explains Sebastian Wuchterl, a research fellow at CERN. \u201cBecause charm quarks are harder to tag than bottom quarks, we relied on cutting-edge machine-learning techniques to separate the signal from backgrounds.\u201d<\/p>\n\n\n\n

The CMS researchers tackled two major hurdles using machine-learning models. The first was the identification of charm jets, which was performed by employing a\u00a0type of algorithm called a graph neural network. <\/p>\n\n\n\n

The second was to distinguish Higgs boson signals from background processes, which was addressed with a\u00a0transformer network\u2014the type of machine learning that is behind ChatGPT but trained to classify events instead of generating dialogues. The charm-tagging algorithm was trained on hundreds of millions of simulated jets to allow it to recognize charm jets with higher accuracy.<\/p>\n\n\n\n

Using data collected from 2016 to 2018, combined with the results from previous searches for the decay of the Higgs boson into charm quarks via other processes, the CMS team set the most stringent limits yet on the interaction between the Higgs boson and the charm quark, reporting an improvement of around 35% compared to previous constraints. This places significant bounds on potential deviations from the Standard Model prediction.<\/p>\n\n\n\n

\u201cOur findings mark a major step,\u201d says Jan van der Linden, a postdoctoral researcher at Ghent University. \u201cWith more data from upcoming LHC runs and improved analysis techniques, we may gain direct insight into the Higgs boson\u2019s interaction with charm quarks at the LHC\u2014a task that was thought impossible a few years ago.\u201d<\/p>\n\n\n\n

As the LHC continues to collect data, refinements in charm tagging and Higgs boson event classification could eventually allow CMS and its companion experiment, ATLAS, to confirm the Higgs boson\u2019s decay into charm quarks. This would be a major step towards a complete understanding of the Higgs boson\u2019s role in the generation of mass for all quarks and provide a crucial test of the 50-year-old Standard Model.\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"

The Higgs boson\u2019s interaction with the heaviest\u00a0\u201cthird-generation\u201d\u00a0quarks\u2014top and bottom quarks\u2014has been\u00a0observed\u00a0and found to be in line with the Standard Model. <\/p>\n","protected":false},"author":2,"featured_media":26352,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[121],"tags":[],"class_list":["post-26351","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-physics"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment.jpg",1100,619,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-200x200.jpg",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-675x380.jpg",675,380,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-768x432.jpg",750,422,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-1024x576.jpg",750,422,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment.jpg",1100,619,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment.jpg",1100,619,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment.jpg",1100,619,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-870x570.jpg",870,570,true],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-600x619.jpg",600,619,true],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-600x600.jpg",600,600,true],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-760x490.jpg",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-550x360.jpg",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-95x65.jpg",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-640x619.jpg",640,619,true],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-96x96.jpg",96,96,true],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/05\/cms-experiment-150x84.jpg",150,84,true]},"author_info":{"info":["RevoScience"]},"category_info":"Physics<\/a>","tag_info":"Physics","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/26351","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=26351"}],"version-history":[{"count":2,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/26351\/revisions"}],"predecessor-version":[{"id":26354,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/26351\/revisions\/26354"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/26352"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=26351"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=26351"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=26351"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}