\u201cIn 30 picoseconds, light moves about one centimeter.\u201d<\/p>\n<\/blockquote>\n
Chris Neu, University of Virginia<\/p>\n
\u201cIn 30 picoseconds, light moves about one centimeter,\u201d said Chris Neu, a professor at the University of Virginia. \u201cWe\u2019re talking about measuring the time of arrival of very fast objects with a very high precision.\u201d<\/p>\n
Some scientists suspect that rare and massive particles that take a long time to decay could move more slowly than lighter, more common particles. This means that when they do finally decay, their \u201cdaughter particles\u201d will be a step behind. The difference would be tiny; a photo finish after a race that is only four feet long. But scientists hope that a precise \u201cstopwatch\u201d detector will help them tell the difference.<\/p>\n
\u201cWe\u2019ll be able to see if any particles are habitually arriving late,\u201d Cardwell said. \u201cThat is inherently interesting.\u201d<\/p>\n
Turning ripples into tsunamis<\/p>\n
The new timing detector consists of two parts: a barrel equipped with roughly 10,000 crystal sensors<\/a>, and end caps coated with hair-thin silicon wafers. While silicon sensors are common inside CMS, this new detector has a special gain layer that amplifies the signal before it is read out.<\/p>\n \u201cA small signal is like a tiny ripple on the surface of the water, and it gets lost among the little waves around it, so it\u2019s hard to tell exactly when it arrived,\u201d said Artur Apresyan, a researcher at the U.S. Department of Energy\u2019s Fermi National Accelerator Laboratory. \u201cThe gain layer turns the small signal into a fast-moving tsunami that stands out clearly from the background, making its arrival time very clear. This amplification feature is not present in other CMS detectors; it\u2019s a new design specifically for timing detectors.\u201d<\/p>\n Currently, scientists at Fermilab are building and testing the sensors and support structures in collaboration with their national and international partners.<\/p>\n \u201cThe work on the end cap timing detector at Fermilab has been a unique possibility for many junior researchers to participate in the design and construction of a novel kind of detector,\u201d Apresyan said. \u201cThese kinds of opportunities are very rare in such large and advanced experiments, and Fermilab provides an exceptional opportunity to allow newcomers to join and learn cutting-edge detector technologies and their applications.\u201d<\/p>\n Unveiling the dark sector<\/p>\n Once the finished detector is installed inside CMS, scientists hope that it will help them separate fast-moving particles from slow-moving dark matter, a mysterious class of particles that are only visible through their gravitational pull.<\/p>\n Dark matter is as good as discovered in the sense that we know it\u2019s there.\u201d <\/p>\n<\/blockquote>\n Tevong You, King\u2019s College London<\/p>\n \u201cDark matter is as good as discovered in the sense that we know it\u2019s there,\u201d said Tevong You, a theorist at King\u2019s College London. \u201cThe problem is that none of the Standard Model particles that we know of can account for the properties of dark matter.\u201d<\/p>\n According to You, many theoretical models predict that \u2014 in addition to the stable dark matter particles \u2014 there could be an entire universe of dark sector particles that might have properties similar to the known particles of the Standard Model.<\/p>\n \u201cDark matter is very stable, but we also know that stable particles like protons are just a small subset of all visible particles,\u201d You said. \u201cMaybe dark matter is just one small part of an extended dark sector that is full of long-lived particles that can decay into visible matter.\u201d<\/p>\n According to Cardwell, the LHC could be producing dark matter. These dark matter particles would eat up a lot of kinetic energy from the proton-proton collisions and turn it into mass via Einstein\u2019s equation, E = mc2. \u201cThis means they have less energy to go fast,\u201d Cardwell said.<\/p>\n When these dark matter particles decay into visible matter, the resulting daughter particles would be lagging behind everything else produced during the collision. This is where the timing detector comes into play.<\/p>\n \u201cIf we can measure the time those particles are arriving, we can figure out if they came from a particle that moved a little slower before decaying,\u201d Cardwell said.<\/p>\n Pinpointing exceptional events<\/p>\n The new timing detector will also give scientists a much clearer view of what exactly is happening when bunches of protons collide inside the LHC.<\/p>\n \u201cRight now in CMS, we send something like 100 billion protons through 100 billion protons 40 million times a second,\u201d Cardwell said.<\/p>\n Every time two bunches of protons cross, about 70 collide. Currently, scientists use the spatial coordinates of the smaller particles produced by the collisions to connect the dots and figure out which particles came from what collisions. But spatial orientation alone won\u2019t be enough when scientists turn on the High-Luminosity LHC<\/a>, which will increase the collision rate by up to a factor of five.<\/p>\n \u201cWhen there are so many collisions, many of them will literally be at the same point in space,\u201d Cardwell said. \u201cBut the collisions don\u2019t all happen at the same time; they\u2019re actually spread out over around 200 picoseconds. With a really, really precise timing detector, 200 picoseconds can suddenly become a very long time; I can slice that 200 picoseconds into a bunch of individual frames.\u201d<\/p>\n These frames will allow scientists to disentangle the messy LHC collisions and pinpoint rare and exceptional events.<\/p>\n \u201cThe cool thing about this detector is that it will make everything CMS does better,\u201d Cardwell said. \u201cIf we are searching for dark matter, if we are measuring the properties of the Higgs boson, if we\u2019re doing anything at all, the quality of every measurement will increase.\u201d<\/p>\n As a theorist, You is excited about this new timing detector because it will open new avenues for research.<\/p>\n \u201cThe best bet for a spectacular discovery at the LHC is through developing new types of searches and new ways of sifting through the data<\/a>,\u201d You said.<\/p>\n Fermi National Accelerator Laboratory is America\u2019s premier national laboratory for particle physics and accelerator research. Fermi Forward Discovery Group manages Fermilab for the U.S. Department of Energy Office of Science. Visit Fermilab\u2019s website at\u00a0www.fnal.gov<\/a>\u00a0and follow us on social media.<\/p>\n","protected":false},"excerpt":{"rendered":"What if Olympic officials could record sprinters\u2019 times only to the nearest minute? \u201cWe would know who started…\n","protected":false},"author":2,"featured_media":401512,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[77],"tags":[49264,2352,18,182110,19,17,133],"class_list":["post-401511","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-cms","tag-dark-matter","tag-eire","tag-high-luminosity-large-hadron-collider","tag-ie","tag-ireland","tag-science"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/116284702287303716","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/401511","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=401511"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/401511\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/401512"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=401511"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=401511"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=401511"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"A](\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2026\/03\/cms-timing-graphic-1024x663.jpg\")
This 3D rendering shows the CMS experiment with its detector subsystems expanded, illustrating the configuration prior to upgrades for the High-Luminosity Large Hadron Collider. The new timing detector will be installed near the region highlighted in green. Credit: CMS\/CERN<\/p>\n\n
![\"A](\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2026\/03\/cms-cern-1024x683.jpg\")
People working on CMS in 2024 are dwarfed by the size of the experiment at the Large Hadron Collider. Credit: CMS\/CERN<\/p>\n