These works are a continuation of those described here.

For approximately one and half weeks from July 24 to August 3, 2025, the right-entry lane at the Route de Meyrin roundabout with Route du Mandement in the direction of France will be closed. Traffic in the Geneva-France direction will be diverted via rue Lect and route du Nant-d'Avril or avenue de Mategnin. More information can be found on the website of the canton of Geneva (in French).

From Friday August 1, 2025, and for 2 weeks, traffic will be alternated at the “Meyrin, Hôpital-de-la-Tour” tram stop. The Meyrin cut-and-cover tunnel will remain open. Trams on line 18 will be replaced by buses (see tpg website Announced works and events).

These works, carried out by the canton of Geneva, will enable the route du Nant-d'Avril to be upgraded for the arrival of the Geneva - Vernier - ZIMEYSAVER Bus à Haut Niveau de Service / fast bus (BHNS-GVZ) by 2027.

For further information, please visit the page Avis de travaux : Info mobilité - BHNS-GVZ, where you can also sign up for the newsletter to stay informed of the latest updates.

Host State Relations service
Tél. : 75152
Relations.secretariat@cern.ch

Since 1 June 2019, only Class 1 laser pointers have been permitted for indoors pointing purposes in Switzerland. The import, possession and use of laser pointers classified as 1M, 2, 2M, 3R, 3B and 4 – as well as of unclassified or incorrectly labelled devices – are strictly prohibited (as per Articles 22 and 23 of the Ordinance to the Federal Act on Protection against the Risks associated with Non-Ionising Radiation and with Sound, O-NIRSA).

At CERN this prohibition is also applicable on the French part of the site.

In this context, and following several incidents where CERN staff or users were stopped by Swiss border guards while carrying prohibited laser pointers, we would like to remind everyone that permitted Class 1 laser pointers are now available for purchase at the CERN stores with SCEM code 54.21.50.001.7.

Please note that any non-compliant laser pointers must be disposed of as electronic waste after removing the batteries. They can be placed in one of the blue containers reserved for electronic equipment (see https://sce-dep.web.cern.ch/waste/what-goes-where).

If you have any questions, please contact: safety-laser-experts@cern.ch. See also the Laser Safety webpage: https://hse.cern/safety-risks/laser-safety

With another successful edition of Bike to Work drawing to a close, the 2025 campaign has once again demonstrated the CERN community’s commitment to the environment, health and camaraderie. Involving the largest number of cyclists to date, this year’s initiative renewed a sense of collective motivation, setting the stage for an even more exciting 2026.

Over the course of the two-month campaign, more than 1161 CERN colleagues signed up and cycled their way to work, joining over 100 000 participants across Switzerland. CERN teams collectively logged over 306 129 kilometres – the equivalent of circumnavigating the globe nearly eight times and a reduction in CO2 emissions of 44 000 kg. Whether commuting from neighbouring France or from nearby Swiss villages, participants embraced the challenge with enthusiasm and energy.

This year the weather helped boost numbers, with unusually warm and sunny mornings encouraging even hesitant cyclists to leave the car at home. Team spirit helped motivate newcomers and seasoned cyclists alike, with a large turnout for the traditional Critical Mass event. Participants also responded well to the encouragement to commute by bike consistently, far surpassing the 50% minimum threshold for successful completion of the challenge.

Alongside seeking to improve well-being and nurture community spirit, Bike to Work plays an important role in the broader push towards sustainable transport at CERN. With increased facilities for cyclists – including additional covered bike shelters, air pumps, and improved shower and changing areas – the Organization is continuing its efforts to make cycling a viable, safe and attractive option year-round. Many participants indicated that they plan to continue cycling beyond the official campaign, a great indicator of long-term behavioural change.

Momentum is already building for next year, and whether you're a seasoned cyclist or have never considered commuting by bike, we encourage you to join the ride in 2026. You don’t need Lycra or a fancy road bike – just a helmet, a bit of curiosity and a willingness to try something new.

Let’s keep the wheels turning, keep on cycling, and for those who have not yet started, see you in the saddle next year!

For three weeks from 7 July 2025, the route de Meyrin cut-and-cover tunnel in the Geneva-France direction is closed from 6 a.m. to 3 p.m. Traffic in the Geneva-France direction is diverted via avenue de Mategnin or rue Lect. More information can be found on the internet website of the canton of Geneva (in French).

From early August to 18 August 2025, the tram line 18 will be interrupted between Bois-du-Lan and Meyrin CERN stops in both directions. Replacement buses will operate. Buses serving the Hôpital de la Tour stop will not be affected.

These works, carried out by the canton of Geneva, will enable the route du Nant-d'Avril to be upgraded for the arrival of the Geneva - Vernier - ZIMEYSAVER Bus à Haut Niveau de Service / fast bus (BHNS-GVZ) by 2027.

For further information, please visit the page Avis de travaux : Info mobilité - BHNS-GVZ, where you can also sign up for the newsletter to stay informed of the latest updates.

Host State Relations service
Tel.: 75152
Relations.secretariat@cern.ch

One hundred years ago, Werner Heisenberg retreated to the island of Helgoland, where he built the foundations of the first full formulation of quantum mechanics. Finding its matrices repugnant, Erwin Schrödinger developed a mathematically equivalent formulation with a wavefunction and a wave equation. Either way, physics would never be the same again: in quantum mechanics, measurement affects what can be known, and predictions can only ever be probabilistic.

A century has not sufficed to fully understand or exploit the theory – and high-energy physicists today find themselves at an interesting juncture. Detector designs are beginning to push quantum limits. Quantum computing is in its “noisy intermediate-scale” era, poised to apply its remarkable parallelism to simulations beyond the reach of classical supercomputers. And with efforts to move beyond the Standard Model at least temporarily frustrated, increasing numbers of theorists are returning to grapple with the foundational assumptions of quantum mechanics. In this special edition, Carlo Rovelli and David Wallace explore a jungle of ideas to resolve questions that have defied consensus since the earliest days of the theory.

Elsewhere in these pages: Fermilab’s last word on muon g-2; DESY brings practical plasma-wakefield acceleration a step closer; ATLAS and ALICE make the first differential measurements of the radial flow of quark-gluon plasma; a farewell to Mary K. Gaillard; and much more.

Read the digital edition of this new issue on the CERN Courier website.

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Be the first to know when the new digital issue of CERN Courier is available, email cern.courier@cern.ch to request to receive a new-issue alert.

Now’s the time to plan your summer and to squeeze in a visit to Science Gateway – and planning has never been easier!

CERN’s Visits service has just implemented a new option allowing individual visitors, families and small groups (up to 11 people) to book visits to Science Gateway online up to one month in advance (groups of 12 or more can still book up to 9 months in advance).

So, if you’re planning to receive guests this summer or you haven’t had the opportunity to discover CERN’s new education and outreach centre yet (or even if you have!), go to https://visit.cern/families-individual-visitors to book your next visit.

On-site registration is still possible, but online booking offers several advantages:

• Guaranteed access to Science Gateway
• Streamlined check-in: simply show your QR code at the reception
• Detailed activity schedule available ahead of your visit.

Some activities with limited capacity (guided tours, lab workshops) still require additional reservation on site after arrival. Find out why.

13 Jun–24 Aug | Knowledge Sharing | Globe of Science and Innovation | Temporary exhibition | EN & FR
Levitation – Glass sculptures by Ján Zoričák

1 Jul–1 Aug | Physics | CERN Main Auditorium | Summer student programme | EN
Summer student lecture programme 2025

1 Jul–1 Aug | Computing | CERN | openlab summer student programme | EN
CERN openlab student lecture programme 2025

10 Jul 16:30 | Knowledge Sharing | CERN Main Auditorium | CERN Colloquium | EN
Synchrotron X-ray radiation damage in protein structure determination: why do we care? by Elspeth Garman

12 Jul 15:00 | At CERN | R3 Terrace, Prévessin Site | CERN Music Club | EN/FR
Hardronic 2025

14 Jul 09:00 | Accelerators | 40/S2-A01 - Salle Anderson | A&T Seminar | EN
High Temperature Superconductivity: status, present and future applications

15–24 Jul | Physics | CICG, Geneva | ICRC | EN
ICRC 2025: 39th International Cosmic Ray Conference

15 Jul 09:00 | Knowledge Sharing | CERN IdeaSquare | IdeaSquare | EN
How innovation happens for real?

15 Jul 19:15 | Knowledge Sharing | CERN Main Auditorium | CERN openlab Summer Student Programme 2025 | EN
Movie Night: "Particle Fever" by Marc Levinson

16 Jul 14:00 | Physics | CERN Main Auditorium | Theory Colloquia | EN
The Strong Interaction at 50 Years: less Puzzling, more Rich, and still Mysterious by Iain Stewart

17 Jul 16:30 | Knowledge Sharing | CERN Main Auditorium | CERN Colloquium | EN
Understanding Cosmic Rays and Gamma-Ray Bursts by Alvaro De Rujula

18 Jul 13:30 | Knowledge Sharing | CERN Library | Archives, Library and Open Science events | EN
Meet the authors with Patrizia Caraveo, Paolo Nespoli and Matthias Maurer

19 Jul 16:00 | Knowledge Sharing | CERN Science Gateway | CERN Public events | EN & FR
STELLAR: A voyage across the Universe with Nobel Laureates and Astronauts

22 & 23 Jul 08:30 | At CERN | Building 29 | CERN Medical Service | EN & FR
Blood donation at CERN / Don du sang au CERN

1–13 Sep | Physics | Pisa, Italy | INFIERI | EN
INFIERI 2025: Intelligent signal processing for frontier research and industry

8–12 Sep | Accelerators | ETH Zurich | ECAART | EN
European Conference on Accelerators in Applied Research and Technology (ECAART 15)

17–24 Sep | Experiments | CERN | DRD1 | EN
DRD1 Gaseous Detectors School

21 Sep–4 Oct | Accelerators | Spain | CERN Accelerator School | EN
Introduction to Accelerator Physics

20–24 Oct | Physics | CERN | LHC Physics Centre at CERN | EN
SEARCH conference

10–13 Nov | Knowledge Sharing | CERN | History Symposium | EN
4th International Symposium on the History of Particle Physics

16–29 Nov | Accelerators | Split, Croatia | CERN Accelerator School | EN
Beam Instrumentation

17–21 Nov | Computing | Valencia, Spain | ROOT | EN
ROOT Users Workshop 2025

This is a curated list of events relevant to the CERN community.
More events are available here: home.cern/events
Indico also shows ALL events happening today, this week and in a calendar view. 

If you would like your event to appear on an upcoming Bulletin events list, please contact bulletin-editors@cern.ch

Thanks to a new collaboration between the CERN Festival Programme and the local Guitare en Scène festival in Saint-Julien-en-Genevois, the CERN community have the chance to buy a limited number of half-price tickets for the evening of Thursday 17 July. The line-up includes Stereophonics, Nada Surf, Wolfmother and more.

Click here (CERN login required) to obtain the code to purchase half-price tickets for 17 July via the festival’s website.

The CERN Festival Programme has been running since 2016, sustained in part by contributions from the CERN and Society Foundation. Supported by the Big Bang Collective, the programme will appear at four festivals across Europe in 2025:

• Colours of Ostrava Festival, Czech Republic (16–19 July)
• Sonorama Ribera Festival, Spain (6–10 August)
• Smukfest Festival, Denmark (7–10 August)
• Rototom Festival, Spain (16–23 August)

If you would like the CERN Festival Programme to include a festival in your country, please contact Connie Potter with details.

Watch the video below for highlights from one of last year’s festivals:

CERN is a key contributor to blood stocks in the region, which according to the Geneva blood barometer remain extremely low. Thanks to your solidarity, CERN ranks 2nd as the region’s biggest blood donor after the Hôpitaux universitaires de Genève (HUG).

The last blood donation campaign on 25 March 2025 was a success, with 159 donors of which 49 were first-timers. A total of 134 donations were collected spanning all blood group types. Thank you to all donors!

To maintain this level of contribution, CERN will hold a two-day blood donation session on Tuesday 22 and Wednesday 23 July, from 8.30 a.m. to 4.30 p.m. in collaboration with the HUG in Building 29.

A further blood donation campaigns will be organised on 18 November.

Before coming to the Building 29 donation point, please make sure that:

• You are in good health and have no symptoms such as fever, cough, a cold or breathing difficulties;
• You are eligible to give blood:
  • Complete the brief online pre-donation questionnaire (in French)
  • Please consult this information sheet and this questionnaire issued by the HUG.
  • Note that only the pre-donation conversation with the nurse or doctor on the day can confirm your eligibility).
  • If returning from travel abroad or arriving from another country, perform the travelcheck on the HUG website (in French)
  • If you have recently been vaccinated against the flu or COVID, ensure 48 hours have passed since receiving the vaccination.
  • Please bring proof of ID with you on the day of the donation.

Save yourself time: pre-book your appointment with OneDoc

The possibility of pre-booking your appointment via the OneDoc platform is made available on this link. Spontaneous donors will be able to come at their convenience without an appointment, mindful that there may be some waiting time on the day.

As a thank you, the HUG will be giving each donor a 10 CHF voucher, to be used in Novae’s Restaurants 1 and 2 at CERN.

We hope to see many of you at the donation point!

Give blood, save lives.

As part of its commitment to sustainable and smart mobility, the SCE department has launched a hitchhiking pilot. Beginning on Monday 16 June 2025, this initiative encourages voluntary shared transport between the Meyrin and Prévessin sites, or within the sites.

This is an additional solution of motorised individual transportation aiming to reduce single-occupancy vehicles. Three hitchhiking spots have already been installed and flagged. Two are in Meyrin: one on Route Fermi, near Bldgs. 376–377–378, and one near Route Pauli, near Entrance B and Route Einstein. One is in Prévessin on Route Adams, closed to the site entrance.

Both CERN and private vehicles can participate. The applicable rules and guidelines are available via this link. Users are invited to provide feedback via QR code surveys available at each station or via this link. For questions or suggestions, please email smart-mobility@cern.ch.

Let’s move smarter together!

Starting 1 July 2025, the Glide application will be officially decommissioned and replaced by Free2Move (F2M), a new mobile solution for booking vehicles from the CERN car-sharing fleet.

This transition is part of SCE department’s commitment to improving mobility services on site. With innovative features, Free2Move will enhance user experience and solve connectivity issues by using Bluetooth to address network problems.

You can register on F2M using CERN SSO and download the F2M app using the QR codes above or by clicking this link: https://sce-dep.web.cern.ch/mobility/car-sharing

Find all mobility solutions at CERN on the Mobility webpages or on the Smart Mobility Brochure. For any questions or assistance, please contact mobility.service@cern.ch.

In March, the Swiss Federal Mint issued a limited-edition silver coin in honour of CERN. Now, a limited number of box sets are available for members of the CERN community to purchase.

The collector’s set includes a 20g silver “burnished flan” coin with a particle collision on the “heads” side (known as “obverse” in numismatic jargon), while the “tails” (or “reverse”) side shows the cross-section of an LHC magnet. The box set also includes a slice of a superconducting cable used in the High-Luminosity Large Hadron Collider upgrade.

Only about 180 box sets are available, limited to 1 box per CERN personal account. The price is 119 CHF per set (which already includes the 10% discount for CERN card holders). Reservations open on Tuesday 24 June at 12 noon on this webpage (accessible only to CERN Primary Account holders). Reserved sets must be personally collected from the CERN Science Gateway shop within 10 days of booking, upon presentation of your personal CERN card and unclaimed sets will be re-released for sale.

Join us in the Main Auditorium at 16:00 on 4 July, the 13th anniversary of the Higgs discovery, for the world premiere of The Peace Particle, a powerful documentary film showing the human stories behind humankind’s biggest experiments.  Filmed to mark CERN’s seventieth anniversary, The Peace Particle combines poetry, music and rare archival footage, alongside special access to the Large Hadron Collider, to reveal how CERN was born from the ashes of war.

Featuring Nobel winning scientists, and one of the last surviving colleagues of Werner Heisenberg, The Peace Particle presents a gripping human story about particle physics and the importance of scientists working together in an increasingly divided world. “This film sets out to show just how much is possible when scientists reject nationalism and work together,” says Director Alex Kiehl. “Today, as wars across the world threaten to undermine open science and peaceful collaboration it’s a vital story.” 

The film features multiple leading scientists from CERN, including current and former Director Generals, Directors, theoreticians and experimental physicists, many of whom will be attending the premiere.

CERN is launching a new group management system (GMS), which has been developed with support from FAP and IT. The new system replaces the old Egroups platform, which will be retired over the coming months.

What’s changing?
You’ll be able to manage all your groups through a new web portal: https://groups-portal.web.cern.ch/
Be sure to update your bookmarks!

There’s no extra work for you – your existing groups and data will be automatically transferred to the new system between July and the end of September 2025. You will receive an email before the migration takes place. If you want to get ahead and move your groups to GMS early, please follow the guide. 

A CSV import and export feature is provided for those who use Excel to manage their group members. We strongly encourage you to move to the simplified GMS format, as described in the CSV documentation. 

For advanced users, there is a REST API interface that replaces the Egroups SOAP API. Migration from the Egroups SOAP API for write clients is expected by the end of September 2025, and for read clients by the end of September 2026.

Why change?
The new GMS is faster and easier to use. It’s directly linked to CERN’s Single Sign-On (SSO) authentication scheme, so any changes you make will take effect immediately. That means:

• New group members get access right away
• No more waiting for group updates to sync
• Better integration with mailing lists and Active Directory (coming soon!).

Just like physical infrastructure, IT systems age over time. GMS is a modern replacement that follows best practices, includes useful new features and reduces the risk of outages.

Need help?
If you have questions or run into any issues, support is available: Submit a request through CERN’s Service Portal.

On 27 May, CERN opened its doors to 17 photographers and invited them to explore, through their lens, the accelerators of tomorrow. This year’s competition, entitled “CERN Photowalk 2025: Future Colliders”, took them to four unique locations, from the High-Luminosity LHC galleries to the Mechanical and Materials Engineering group’s main workshop.

The result? 165 stunning photo submissions. The local jury shortlisted the best 20 pictures and selected the first two winners. Now we are asking the CERN community to help choose the third winner.

The three winning photos will be included in the upcoming Global Physics Photowalk, joining the entries from other research institutions around the world.

Do you need help deciding? Consider the following questions when you vote:

• Does the photo fit the theme of “Future Machines”?
• Does it have a futuristic feel?
• Does it represent CERN?
• Is it an original, unique perspective on the machines we already know (and love)?

Voting is open until 30 June 2025, 5.00 p.m. CEST. Vote here (behind SSO).