Our CMS physicists at CERN are working on something big: the first prototype slice of HGCAL, the largest silicon-based detector ever built. This is a step in the plan of technical upgrade CMS will undergo starting in 2026. 🏆HGCAL Image of the Month 📸Andre David

CMS heavy-ion physicists participated last week in Initial Stages 2025 in Taipei. Thanks to our colleagues across the collaboration for their hard work, and to the IS2025 organisers for hosting such a vibrant exchange of ideas.

A cosmic choreography at the tiniest scales! 🩰 CMS researchers study light-ion collisions, and provide robust evidence of how the shapes of the colliding nuclei guide the collective flow of particles 🌊 📍Read more: cms.cern/news/collect...

Neon lights up the LHC! CMS scientists study the first-ever neon-neon collisions, and comparing to oxygen-oxygen, xenon-xenon, and lead-lead, find interesting insights into quark-gluon plasma – the hottest state of matter🌡️ 📍Read more: cms.cern/news/lhcs-fi...

CMS scientists study the first-ever oxygen–oxygen collisions at the LHC and find the first signs in light-ion collisions of quark–gluon plasma – the state of matter that filled the universe just after the Big Bang 💥 Read more: cms.cern/news/lhcs-fi...

CMS deepens our understanding of the early #universe by studying the first ever oxygen-oxygen and neon-neon collisions at the #LHC! With the effort of the whole group, results from these unique collisions are already being shared at major conferences. Read more here 👉 cms.cern/news/cms-ini...

✨Turning light into heavy force carriers: For the first time, CMS has observed two photons fusing to create a pair of W bosons! Read the full physics briefing to find out more: cms.cern/news/when-li... #physics #physicsnews #science #research

🤩 In a first-of-its-kind search at the LHC, CMS probed Higgs boson decays to new light particles that give charged hadrons and muons. The results: such decays, if they occur at all, are limited to less than 0.01% of all Higgs boson decays. Read more: cms.cern/news/hunting... #physics #research

Meet Annabel, Walter and Amal — just a few of this year's CERN (@cern.bsky.social) summer students working with the CMS experiment — and get an inside look at their incredible experience! 📽️Watch here: youtu.be/pSKtNaNbZ9w

CMS presents its most precise and comprehensive measurement of the Higgs boson yet! 📏 Read more about how combining different studies made this remarkable result possible: cms.cern/news/pieces-...

On the hunt for an ungovernable heavy boson 🕵️ CMS investigates Z boson decays which would rebel against the established behavior of lepton-flavor conservation. 👉Read more: cms.cern/news/hunt-ru...

Did you miss the recent ‘Progress in Physics’ article featuring a CMS result on quantum entanglement in top quark–antiquark pairs? Read it on Physics World: physicsworld.com/a/probing-qu... #Science #CERN #sciencenews #physics

A novel probe of the Higgs-charm interaction: CMS researchers take a first look at W boson charge asymmetry produced in association with a Higgs boson. 📌Read more: cms.cern/news/cms-mea...

CMS has completed a new Data Acquisition System (DAQ) room! This room is key to increasing the data processing capacity from 2 Tb/s to 50 Tb/s for Run 4 — roughly 500,000 times more than a typical household fibre-optic internet connection. Read more: cms.cern/news/cms-com... #science #CERN

CMS' Marina Passaseo interviews Barbara Storaci and Sarah Seif El-Nasr about their journey from particle physics at #CERN to working in sports at #UEFA! 🎙️ Hear how #science gave them confidence on and off the pitch. Watch the full video here: youtu.be/TgSci4JSdaI #sports #physics #football

An Optical Trigger MotherBoard for the Cathode Strip Chamber that enables communication with another muon detector, the Gas Electron Multiplier. The integrated triggering system enhances muon detection by combining data from both detectors. 🏆 Muon Image of the Month 📸 D. Morse

This is one of the five double disks for each of the two Tracker Endcap Double Disks (TEDD), being built for Hi-Lumi LHC. Each disk is made up of two half-disks or "Dees". Two disks, separated by around 2 cm, form a double disk! 🏆 Tracker Image of the Month 📸 A. Mussgiller #science #particlephysics

How do you weigh the W boson using hadrons? ⚖️⚛️ For the first time ever at a hadron collider, CMS has managed to do it! Read more: cms.cern/news/how-wei...

🚀 In hot pursuit of supersymmetry: CMS explores a wide range of final states with boosted particles using a razor-sharp analysis. The result? One of the most comprehensive searches for supersymmetry yet. Read more: cms.cern/news/all-rou... #science #physics #experiment

Our kind of biscuit tray — but with hexaboards for the future High Granularity Calorimeter (HGCAL), planned for the Hi-Lumi LHC upgrade. The increased granularity of HGCAL will help better distinguish signals from different particles.⚛️ 🏆 HGCAL Image of the Month 📸 HGCAL team #CERN #science #physics

All credits to CMS detector & collaboration! 📸 These event displays are visual representations of particle collisions, reconstructed from signals recorded by CMS. As particles pass through detector, they leave traces, which are processed & transformed into stunning displays by specialised software.

One photon short! CMS breaks new ground by using AI to hunt for exotic Higgs boson decays. ⚛️ Read more: cms.cern/news/one-pho... #CERN #CMSexperiment #physics #science #HiggsBoson #particlephysics

What are conference talks actually like? Listen to CMS' physics coordinator, Roberto Salerno, as he explains how CMS is pushing the boundaries of physics in his talk at the EPS Conference 2025. ⚛️ www.youtube.com/watch?v=nBbG...

🤔Could the Higgs boson have a shadowy cousin? CMS is pushing boundaries with #AI in the search for the dark Higgs – a potential link to #darkmatter 😲 👉To find out more about this study, read the physics briefing on our website: cms.cern/news/higgs-b... #physics #physicsnews #particlephysics

This tray is part of the CMS MIP Timing Detector (MTD), to be installed around the Tracker for the Hi-Lumi LHC upgrade. With ~35 ps time resolution, it will help CMS maintain event reconstruction accuracy even with 5x more collisions. 🏆MTD Image of the Month 📸A. Benaglia

✨Top Quark: The Lone Traveller✨ In the latest episode of the top quark saga, CMS reveals for the first time how a single top quark is produced in a mode called "t-channel" in a new, uncharted territory: 5.02 TeV! Read the CMS physics briefing for more: cms.cern/news/top-qua...

The 2025 European Physical Society (EPS) Conference on High Energy Physics took place in Marseille from 7th to 11th July 2025, and CMS was there, represented by many scientists and posters! Can our scientists explain their research in less than one minute? Let’s find out: youtu.be/_DuzMO4hKP0?...

CMS goes to the optometrist and learns how to identify electron-positron pairs travelling so closely that their signals get merged! Read the physics briefing here: cms.cern/news/cms-has...

👀 An intriguing physics spy story – by studying a Higgs boson decaying into two photons, CMS scientists are investigating whether it is going off-script in its interactions. ✨ Find out more by reading our briefing: cms.cern/news/beyond-...

Look at tiny hexaboards getting tested!🔬 These are building blocks of the silicon section of CMS high-granularity calorimeter(HGCAL). It will be installed during the upgrade of the detector for Hi-Lumi LHC later this decade, when CMS will have more collision events to capture. 📹: Axel & Gizem

Elusive romance of top-quark pairs observed at the LHC The @cmsexperiment.bsky.social and @atlasexperiment.bsky.social at CERN’s Large Hadron Collider have observed an unforeseen feature in the behaviour of top quarks that suggests that they form a fleeting union

An unexpected duet of heavyweights! Last year, CMS announced the observation of a top quark antiquark bound state, which could be toponium – this has now been confirmed by the @atlasexperiment.bsky.social! Roberto Salerno, a physics coordinator of CMS, explains. Read more: home.cern/news/press-r...

🎇 The first-ever oxygen collisions at the LHC happened today! he teams at CMS are working to capture the data from these unique collisions. 👇Here you can see one of the first oxygen-oxygen collisions! 🤔 Read more about this special week here: cms.cern/news/first-e...

Today marks 13 years since scientists at the CMS & ATLAS experiment at CERN announced the discovery of the Higgs boson. It was a major milestone in our understanding of how the universe works. Watch CMS physicist Ansar explain Higgs boson discovery and what mysteries remain: youtu.be/TZM1k58JWyM

On each end of the tracker at the centre of the CMS, the "bulkhead" is the region where all the connections reach the tracker and get the data out. A lot of power cables, fibers, and pipes run through this rarely accessed part of the detector. 🏆Tracker Image of the Month 📸 G. Haza

Is there a link between UEFA and CMS? ⚛️⚽ Stay tuned to know! #cmsexperiment #science

🎇The first ever oxygen and neon LHC collisions are being studied by CMS! 🎇 Here you can see one of the first collisions between protons and oxygen nuclei recorded by the CMS detecor, and part of the team leading the research! Stay tuned for morei in the coming days... cms.cern/index.php/ne...

🤔What’s 100 times lighter than a proton and hiding in the data? CMS sets the most sensitive limits yet on ultra-light exotic particles using #MachineLearning and Higgs bosons giving electron pairs! Read more: cms.cern/news/chasing... #cern #physics #physicsnews #higgsboson #particles

CMS takes part in a fun colour run in Cessy, France - the location of the detector! 🏃🏃‍♀️ With a bunch of volunteers and a stall, adults and children alike played games and learned about CMS, with dedicated tours to follow! 🥳 cms.cern/news/cms-202...

Congratulations to the CMS Spokesperson Gautier Hamel de Monchenault on his appointment as the Director for Research and Computing at CERN, effective January 1, 2026! 👏 Nominated by Mark Thomson and approved by the CERN Council, Gautier will bring a wealth of experience to this position.

🌟 Celebrating excellence at CMS! 🌟 Discover the highlights and incredible achievements from last week's CMS Awards! See the brilliant minds recognized for their contributions and view photos from the ceremony. 🔗 cms.cern/index.php/ne...

This account is now active. For the next couple of days, we'll post recent #CMSPaper and #CMSPAS from the last couple of months. Afterwards, it will post the latest results from @cmsexperiment.bsky.social just like x.com/cmspapers and mastodon.social/@cmspapers.

Jasmine working on one of the HGCAL "Hexaboards", following its successful test using a novel system (developed at @tifr.res.in, India) for checking connectivity from delicate bonding pads and the HGCROC processing chips, without touching the bonding pads! 🏆 HGCAL Image of the Month 📸 Shilpi Jain

👀Who needs eyes when you have DeepMET? 👉Learn how this smart algorithm developed by CMS is helping us see escaping invisible particles better than ever before: cms.cern/news/teachin... #machinelearning #cern @cern.bsky.social #physics

📸The CMS Collaboration 2025! CMS took a group photo of those attending the June CMS week.📸 Did you know CMS has over 6000 people working for the experiment? Not all of them could be at CERN for this photo, as they are located all around the globe 🌍 📸 Michael Hoch #cern

The 2025 LHCP conference recently took place, and CMS was there, represented by many students and posters! ⏱️ Can our scientists explain their research in less than one minute? Let’s find out! youtu.be/8hIyJZkk9OY

🥇 For the first time ever, CMS fully reconstructs the excited states of three beauty mesons and measures their masses directly! An incredible result, as over the last 30 years they have only ever been measured indirectly! 🎉 Find out more: cms.cern/news/b-meson...

CMS recently announced 14 new results at the LHCP conference 🥳 Here is a page with a synopsis of our main highlights and a list of all our results: cms.cern/news/cms-lhc...

This is a Tileboard Printed Circuit Board, which will be placed in the CE-H section of HGCAL at the High-Lumi LHC, hosting scintillator tiles, silicon photomultipliers (SiPMs) to detect light from them, and read out electronics🔦 📸Gizem Gul Dincer 🏆HGCAL Image of the Month

🥳 CMS inaugurates its new control room - celebrate the day with us with a sneak peak of the inauguration, clips of the control room, and the new art pieces that are going up next to it: www.youtube.com/watch?v=4p7j...