Overview of data taking operations in ALICE

The overall coordination of the operations of the ALICE experiment is under the responsibility of Technical Coordination (TC). The CB appoints a Run Coordinator (RC) and a Deputy Run Coordinator (DRC) who are responsible for the data taking operations of the ALICE detector for a one year running period and represent the experiment at the LHC accelerator control center (CCC).

During physics data taking period, RC is assisted in the daily coordination work by a Run Manager (RM) for the duration of a 2 week period. Each subsystem nominates a System Run Coordinator (SRC), who is responsible for the detailed organization of the real-time operation of the subsystem and provides the interface between the RC and the project. The shift crew has the task of operating the experiment for an 8-hour shift period. It is headed by a Shift Leader (SL) who is in charge of implementing the shift plan defined in the run coordination meetings and directing the shift operations.

Data Taking in 2022

Central Shifts 

  • Due to the heavy duties of the upcoming beam physics ALICE will be operated by 4 central shifters 

    • Shift Leader (SAMS name: SL)

    • Data Acquisition ECS/FLP/CTP/EPN-IT (SAMS name: ECS)

    • Detector Control System (SAMS name: DCS) 

    • Quality Control QC/PDP/EOS/GRID (SAMS name QC)

  • All the shifts will follow the MMAANN schedule (a block of 6 days will carry 2 mornings, 2 afternoons and 2 nights, unsplittable unless very critical cases happen such as health problems, accidents) 

  • SL and DCS shifts (and relative trainings) must be taken always in presence

  • QC and ECS shifts (and relative trainings) are strongly preferred in presence,
    however due to the current pandemic situation this two shift roles will offer the option of virtual shift blocks

Virtual Shift Blocks

In 2022, remote operations are offered in the form of virtual shift blocks for the ALICE members who suffer travel restriction or for other serious reasons.

VSB use the same physical infrastructure of the 2021 remote operations (ROS, Remote Operations Site). So the shifter has to connect to the ARC from an institutional workstation which ensure reliable connection an operability. 

What is a Virtual Shift Block (VSB)?

A virtual  shift block is simply a shift block booked in SAMS requesting remote participation. At the time of booking the block is reserved and if the user request it to be virtual, SAMS will notify the RC who will approve or reject the request based on the provided justification.

Here are some important information you should know before requesting VSBs:

  • SL and DCS shifts do not offer virtual shift blocks: all blocks are in presence.
  • QC and ECS shifts DO OFFER virtual shift blocks for real and training shifts. This means that you can request one or more shift blocks to be taken remotely with a justification.
  • Requesting a virtual blocks for ECS is foreseen ONLY in the commissioning phase when there are no collisions ongoing: according to the present LHC schedule up to May 31st. In other words, after May 31st the ECS shifts are all in presence and requests for VSB will be rejected.
  • Requesting a virtual blocks for QC may be possibile also for the beam period except the HI period.
  • For the HI period for all shifts, presence is mandatory and no VSB will be allowed.
  • The justification to request a VSB should be related to the impossibility to travel to CERN.
  • For QC and ECS training shifts the same virtualization rules of normal shifts apply however it is not possibile to have BOTH trainee and regular shifter going virtual. In other words, the system will always require that at least one of the two is in presence.
  • Since a virtual shift block is a regular shift that is virtualized on request it is immersed in the overall MMAANN schedule structure so a virtual block will also be in the form MMAANN (you will have to follow the CERN time zone) 
  • Virtual shifters will be signalled in SAMS both in the booking table and in the big screen and crew screen with a PURPLE card so the RC team is aware the person will not show up in the ARC.
  • Virtual shifters will receive a mail have to connect to the ARC zoom with a calendar that matchs their time zone with the CERN time zone.
  • Communication with the SL must be lively and via voice/video (camera must be on) and the ZOOM chat (not MatterMost).
  • Virtual shifters will not be picked up by SAMS for the SLIMOS role.
  • Instructions on how to access the ARC computing resources from outside CERN can be found here 


How to book a VSB

  • In SAMS book the shifts selecting the block and clicking the regular GREEN button (this is nothing new).
  • once the block is assigned, select it again and press the PURPLE button (request virtual shift): provide a justification and click OK. Now your name should be shown in PURPLE font.
  • NOTE: when your name is in PURPLE the virtualization request is still under approval. If the request is approved by RC your name will be then shown in REVERSE PURPLE. Only at this point the VSB is confirmed. 
  • If the request is rejected the booking is lost and you have to rebook another slot or the same slot in presence.


Run Managers

  • ALICE central shifter will be supported by Run Managers who will be in charge of coordinating the day-by-day operations at P2 for two weeks. Among the duty of the RM: 
    • Assist the SL and intercept low level exceptions that do not need the intervention of the D/RC, escalade to D/RC in any other case
    • After the RC Daily Meeting compile and send the daily instructions valid for the current crew (Afternoon) and the two subsequent crews (Night and next Morning)
    • Scan the logbook entries from the shifters and expert and provide a report of the most significant ones to the D/RC
    • Run the Daily Meeting (max 30m) compiling the minutes and sending them via email to P2info and posting them in the Logbook
    • Compile the minutes during the RC Weekly meeting and sending them via email to P2info and posting them in the Logbook


  • The ALICE shift calendar starts on Feb, 21st 2022 without night shifts, full shifts will start on Feb, 28th. 
  • SAMS Classes can be found here
  • SAMS training shifts and regular shifts booking can be found here
  • The current shift crew can be found here
  • The full RC crew and SRC crew can be found here

SLIMOS shifts

ALICE shift booking : Procedures 

The shift booking is opened

  • Onsite shift booking procedures
    1. SLIMOS permission (the one with a 3 year expiration date) in SAMS is mandatory
    2. Sign up for the shift class ( will give you already the possibility to move to step 3. 
    3. Sign up for the 3 day training shifts
    4. Book the general shifts 


Access list to be requested by the user in ADAMS 

  • OC2 general CERN access - mandatory
  • ALI-ACR control room access - mandatory
  • ALI-COF kitchen access - optional but recommended 
  • ALI-KEY-CABINIET-SLI needed to get the status SLIMOS in SAMS - if missing does not prevent the physical access to the control room, however will not allow the propore shift crediting due to the missing SLIMOS status. 

access list




Permission migration from 2021 into 2022

  • Whoever was qualified as SL/ECS will be qualified for both SL and ECS in 2022
  • Whoever was qualified as EPN/PDP will be qualified for QC in 2022

if you experience problems with SAMS shifts or class booking or permissions please contact the SAMS technical support

Note: the permission validity is not extended.

Also note that the classes and training material is being reviewed by a Training Coordinator so even if you had classes and training in 2021 you are strongly encouraged to take a refresher class and training if possible.


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