15th HL-LHC Collaboration Meeting, CERN, 29 September - 2 October 2025

29 Sept 2025, 08:00 → 3 Oct 2025, 17:30 Europe/Rome

The HL-LHC Collaboration Meeting will return to CERN in 2025, marking the fourth time the event is hosted on the CERN site since the project’s kickoff meeting in 2011. The 15th HL-LHC Collaboration Meeting will be held in person from 29th September to 2nd October 2025, at CERN’s Science Gateway. As in previous editions, the meeting will include a restricted session for the 15th HL-LHC Collaboration Board. This year’s meeting holds particular significance as it coincides with the conclusion of the mandate of CERN’s current Director-General, who has overseen the HL-LHC project since its official approval in 2016. Hosting the meeting at CERN offers a timely opportunity to bring together the outgoing and incoming CERN management and it will highlight the project’s status as it enters a pivotal phase—transitioning from production to installation during Long Shutdown 3 (LS3), scheduled to begin in June 2026. A key highlight will be the completion of installation and start of operation of the IT String, a full test stand located in CERN’s SM18 test hall that replicates the left side of the HL-LHC insertion region at Point 5. This essential facility is designed to validate key HL-LHC technologies in a complete circuit setup, paving the way for their installation in the new HL-LHC underground areas and the LHC tunnel. Finally, this year will also see the transition of project leadership, with Oliver Brüning being newly appointed Director for Accelerators and Technology at CERN, with effect from 1st January 2026. The programme includes a Welcome Drink on Monday 29th September, a site visit to the IT String and the new HL-LHC galleries at Point 1, and a collaboration banquet on Wednesday 1st October. Participation in the meeting is by invitation only, and registration is mandatory and without fee. Registration deadline: 10th September 2025. Data Privacy Protection Policy : OC no.11 - ATS Events Privacy Notice

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Monday 29 September

08:00 → 09:00 Registration at the Science Gateway

09:00 → 10:20 Plenary session 1 - Monday AM

09:00 Welcome

Speaker: Fabiola Gianotti (CERN)

09:05 Welcome

Speaker: Mark Thomson (CERN)

09:10 HL-LHC Project status

Speaker: Oliver Bruning (CERN)

09:40 Status of US-AUP contribution

10:00 Status of LQXFA cryostating and schedule to finish LQXFA10

Speaker: Sandor Feher (Fermi National Accelerator Lab. (US))

10:20 → 10:50 Coffee break

10:50 → 12:30 Plenary session 2 - Monday AM

10:50 Status of D1 and HPRF

Speaker: Tatsushi Nakamoto (KEK)

11:05 MCBXF coil production and assembly

Speaker: Fernando Toral (CIEMAT - Centro de Investigaciones Energéticas Medioambientales y Tec. (ES))

11:25 Status of D2 corrector magnets (MCBRD)

Speaker: Qingjin Xu

11:40 Status of WP3 Magnets for Insertion Regions (including MQXFB)

Speaker: Susana Izquierdo Bermudez (CERN)

12:15 Status of D2

Speaker: Stefania Farinon (INFN e Universita Genova (IT))

12:30 → 14:00 Lunch break

14:00 → 15:30 Plenary session 1 - Monday PM

14:00 Status of WP4 crab cavities

Speaker: Rama Calaga (CERN)

14:30 UK contribution: Status of DQW cryomodules

14:50 RFD Crab Cavity contribution from the U.S. - Status, issues and delivery dates

Speaker: Leonardo Ristori (Fermilab)

15:10 Canadian contribution: Status of RFD cryomodules

• progress on TC0
• preparation for TCM1-4

Speaker: Robert Laxdal

15:30 → 16:00 Coffee break

16:00 → 17:40 Plenary session 2 - Monday PM

16:00 WP2 Accelerator Physics: Performance of the HL-LHC, from baseline to alternative options

Speaker: Rogelio Tomas Garcia (CERN)

16:20 WP5 Collimation

Collimation studies and beam loss experience from Run3 - halo population, IR7 optics, lifetime,… Status of Collimator production

16:40 WP16 IT String & Hardware Commissioning

IT String status, ROE from assembly, preparations for cooldown and operation, SVPM for IT String

17:10 WP15 Integration and (De-)Installation

LS3 installation plans and equipment readiness, preparation of (de-)installation during LS3

18:00 → 20:00 Welcome drink

Tuesday 30 September

08:30 → 11:00 Collaboration Board (restricted)

08:30 → 11:00 Guided tour of HL-LHC P1 and IT String (SM18)

11:00 → 11:30 Coffee break

11:30 → 13:00 Plenary session 1 - Tuesday AM

11:30 WP9 HL-LHC Cryogenics: status of production and installation

Speaker: Vanessa Gahier (CERN)

11:50 WP6A Cold Powering

The presentation provides an update on the production and qualification of the Cold Powering Systems for the HL-LHC magnets. It also outlines the status of activities at the collaborators’ site, the progress of procurement, and the schedule for installing the eighth series of systems in the LHC underground during LS3.

Speaker: Amalia Ballarino (CERN)

12:20 WP6B Warm Powering

Preparations of WP6b equipment + SW for powering tests in the IT String + tunnel installation

12:40 WP7 Machine Protection & Availability

Speaker: Daniel Wollmann (CERN)

13:00 → 14:30 Lunch break

14:30 → 16:00 Plenary session 1 - Tuesday PM

14:30 WP12 Vacuum & Beam Screen

Speaker: Vincent Baglin (CERN)

14:50 WP8 Collider-Experiment Interface

Status of interfaces with Experiments, TAXN/S production,VAXS box…

Speaker: Francisco Sanchez Galan (CERN)

15:05 WP10 Energy Deposition & R2E: Overview of energy deposition and radiation levels at the HL-LHC

Speaker: Giuseppe Lerner (CERN)

15:20 WP13 Beam Instrumentation

Beam Instrumentation baseline for HL era and status of the UK contributions (BGI, Coronagraph, BGC on test stand, …)

15:40 WP14 Beam Transfer & Kickers

Design decisions for beam dumps, installation status of MKI cool, TCDS upgrade...

Speaker: Chiara Bracco (CERN)

16:00 → 16:30 Coffee break

16:30 → 17:30 Plenary session 2 - Tuesday PM

16:30 WP17 Infrastructure, Logistics & Civil Engineering

Status of tech. infra. Installation and cores drilling plan (YETS tests)

16:50 WP18 Controls Technologies

Development for DIOT and return of experience from FRAS, WP7,…

Speaker: Javier Serrano (CERN)

17:10 WP19 Alignment & Internal Metrology: FRAS at SCT and IT String – status of sensor & adjustment system qualification and software preparation

Speaker: Mateusz Sosin (CERN)

18:30 → 21:30 Transfer from/to CERN and HLCB Dinner (by invitation)

Wednesday 1 October

08:30 → 10:30 Parallel sessions 1

10:30 → 11:00 Coffee break

11:00 → 12:30 Parallel sessions 1

12:30 → 14:00 Lunch break

14:00 → 16:30 Guided tour of HL-LHC P1 and IT String (SM18)

14:00 → 16:00 Parallel sessions 2

16:00 → 16:30 Coffee break

16:30 → 17:50 Parallel sessions 2

19:00 → 23:00 Collaboration Banquet

Thursday 2 October

08:30 → 10:30 Parallel sessions 3

10:30 → 11:00 Coffee break

11:00 → 12:30 Parallel sessions 3

12:30 → 14:00 Lunch break

14:00 → 15:40 Parallel sessions 4

15:40 → 16:10 Coffee break

16:10 → 16:30 Close-out (start time tbc)

16:30 → 18:30 Steering Committees

Friday 3 October

08:30 → 11:00 Guided tour of HL-LHC P1 and IT String (SM18)

08:30 → 10:30 Steering Committees and/or Satellite meetings

10:30 → 11:00 Coffee break

11:00 → 12:30 Steering Committees and/or Satellite meetings

12:30 → 14:00 Lunch break

14:00 → 15:30 Steering Committees and/or Satellite meetings

15:30 → 16:00 Coffee break

16:00 → 17:30 Steering Committees and/or Satellite meetings