ALICE shift booking

  • Shifts can be booked using the Shift Accounting and Management System web tool.
  • In order to book any of the central shifts, the SLIMOS permission in SAMS is mandatory. 
    • Online course must be completed (ALICE - Shift Leader in Matters of Safety (SLiMoS) at
    • Afterwards, the SLIMOS permission is automatically granted when the "2285K1-005 ALICE KEYS CABINET SLI" access is validated via EDH (
      • Access requests via EDH can only be done when one is properly registered as USER (or STAFF etc.).
      • In case a person passed SLIMOS course and cannot make the request ("You may not create requests for this person on this permission. Access denied by Page security check"), one should send a mail to to have the permission manually added into SAMS (allowing the booking of shifts).
    • Please refer to the access request page
  • Jump to the shift instructions page

Operations in ALICE

  • Run Coordination

The overall coordination of the operations of the ALICE experiment is under the responsibility of Technical Coordination (TC). The TC 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).

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.


  • Shift overview

There are 4 kinds of shifts

  1. Central shifts
  2. Central training shifts
  3. Detector shifts
  4. On-Call shifts

  • 1. Central shifts
    • Shift Leader (SL)
      • The SL is responsible for the routine operations and ensures that the daily program of data taking as approved by the Physics Board (PB) and implemented by the Trigger Coordination (TriCo) and the Run Coordination (RC) is enforced. Any action which impacts on the planned shift instructions should be promptly communicated to the Run Manager (RM). The SL is expected to have sufficient knowledge on the running of the experiment. It is therefore recommended that the SL has gained experience in either one of the other central shifts or on-call shifts.
    • Experiment Control Shift (ECS)
      • The ECS shifter is in charge of operating the Data Acquisition (DAQ), Central Trigger (CTP) and High Level Trigger (HLT) systems according to the instructions received from the SL. The ECS shifter must stay focused in order to promptly execute the required operations and constantly monitor their outcome. The ECS shifter must never act on his own initiative, for instance stopping or starting a run unless the SL instructs him/her to do so. Of course, if the ECS shifter, while monitoring the operations, observes any anomaly he/she must report it to the SL who will decide which action to take.
    • Detector Control Shift (DCS)
      • The DCS shifter is in charge to perform all the actions related to the detector slow control (i.e. changing the physical state of a detector by altering the operational voltages) as well as the interactions with the accelerator systems. As the ECS shifter, the DCS shifter must never act by his own initiative. The DCS shifter has to remain alert and if any anomaly is found he/she must report it to the SL who will decide which action to take.
    • Data Quality Monitoring Shift (DQM)
      • The DQM shifter has the critical task to monitor the quality of the data flowing into the ALICE permanent storage via a series of histograms  which are updated during the run and signal potential anomalies in the raw data which must be forwarded promptly to the SL. The DQM shifter is also in charge of monitoring the response of the part of the OFFLINE system which treats critical information for the data reconstruction.
    The central shifts are booked via SAMS. They strictly follow the MAN scheduling. In order to book a central shift of a specific type you must attend the corresponding training class and take a block of training shifts.
  • 2. The Central Training Shifts
    • Central training shifts are mandatory in order to be able to carry out regular shifts. The training shift block runs over three consecutive days and does not follow the MAN schedule. This would mean that you could e.g. have either three consecutive morning or evening training shifts. As a trainee you have the obligation to follow closely the operations performed by your trainer for the first two days. Your trainer has the obligation to provide you with all the required information and to answer your questions. On the third day of your training shifts you are required to swap with your trainer who has to assist while you perform the actual shift as a "shadow" shifter. This model is called TTS (Training, Training, Shadow). In order to book a TTS block you must have attended a training class. In addition to the training class there is also a test which you must pass before being allowed to perform regular shifts. 
  • 3. The Detector Shifts
    • These shifts can only be occupied during commissioning periods or special running periods (typically HI runs). Detector shifts are opened by the Run Coordinator (RC) upon request of the SRC  (System Run Coordinator) who then manages these. In order to be qualified for a detector shift you have to gain expertise on that particular system. The SRC provides ad-hoc training and gives permission according to his judgment of your expertise to take detector shifts for his/her system. Once the shifts are open and you are qualified by your SRC you can book these. Detector shifts are booked according to the MAN system for ALICE central shifts. 
  • 4. The On-Call Shifts
    • On-Call shifts are booked by experienced detector shifters. The On-Call qualification for a certain system is given by the corresponding SRC according to his/her judgment. Ad-hoc training sessions can be required to become an On-Call shifter. On-Call shifts are booked via SAMS on a day-by-day basis and last 24h. During this time you are not required to be at P2 however you are required to carry a CERN mobile so that you can be called at any time of the day in case of problems with the system for which you are the on-call. If the problem cannot be solved remotely you must be able to come to P2 within 30 min after the call. Therefore you would need to have proper transportation and cannot leave the CERN area when you are on-call. As an On-Call shifter you can be asked by the SRC to attend the daily Run Coordination meeting at P2 at 16h30. Remote participation is possible however physical participation is preferred especially in case of complex problem solving scenarios. If for any reason you cannot attend the daily meeting you must inform the Run Manager by email or phone and provide a written report.