Here, you can find information relative to the beamtime planning at PHELIX. In case of questions, please email: Beamtime-Phelix (at)

Proposal review and experiment scheduling

During the construction of FAIR, proposals are evaluated by the PPAC committee. Laboratories are invited to inquire about the beamtime availability and schedule for the next proposal evaluation. Once a proposal is approved, the principal investigator is personally informed and he*she should contact the laser team to schedule the beamtime.

The experiment design review

Because experiments driven by PHELIX require a close work between the laser team and the experimental team, the PI is requested to present an experiment design review, at least two months before his*her beamtime. The beamtime will only be scheduled after a sucessful experiment design review has been presented. The guideline for preparing the design review can be downloaded here. These are some of the points that must be covered during the review:

  • Statement about the goals. The goals of the beamtime must be stated. The laser team verifies that the goals are in line with the proposal.
  • Experiment layout. The PI is invited to show that his*her experimental setup matches the capabilities of the PHELIX target areas. For this, drawings of the different target areas can be requested in DXF or STEP format. A drawing of the PLH chamber is available here. More details about the PHELIX target area can be found here.
  • Shot plan. The number of shots delivered by PHELIX is about 30/week of beamtime. The PI must state how he*she intends to use these shots. In addition, the types of targets to be used must be communicated because different targets imply different levels of risk for the machine.
  • Safety regulations of GSI must be followed.

Preparing your beamtime

Users can visit the GSI user page and the side of our Welcome Office to get information about GSI and services around GSI.

We would also like to mention some more details which, taken into account early in your preparation, might not mean too much additional effort, but on which we have to insist in order to maintain our operation standards and/or will make it easier for you to make good use of your beamtime:

Working in a clean room environment

The PHELIX laser hall (PLH) is a clean room which includes the petawatt target area and x-ray laboratory. For these rooms, standard clean room practice is in effect and you are requested to follow it.  In particular: 

  • We do not allow cardboard boxes in the lab and try to avoid paper whenever possible to maintain our cleanroom environment. So especially if you plan to bring large amounts of equipment, it will certainly help if this is packed in cleanroom compatible bags (ideally several layers) or containers which can be easily cleaned before bringing them into the laboratory.
  • For the same reason, we have to insist that even in summer time, you can only enter the lab in clothing appropriate for class 100000 cleanrooms which for example excludes shorts.

Vacuum equipment for the petawatt target chamber

The petawatt target chamber is a large vacuum vessel and as such will host a lot of your equipments. Material and diagnostics which are to be installed in or connected to the target chamber vacuum need to meet standards for 1E-6 mbar. This e.g. includes the use of vacuum compatible lubricants, venting of internal cavities (typically screw holes) and clean or easily cleanable surfaces. Plastics and adhesives have to be chosen with care and should be avoided wherever possible. Please be aware that in the PW area, as part of the shot sequence, the target chamber vacuum will be directly connected to the compressor chamber where we have an upper limit for shooting of 5E-5 mbar. While the basic setup in the chamber (parabola and focus diagnostics) will allow for a cyclic pump down time of about 30 min, a typical setup in which the above things have been considered will increase this to about 40 min. This time can, however, be increased a lot if these rules are neglected, which will make it hard to keep up with the laser cycling time of 90 min.

During your beamtime at PHELIX

The following is a list of the key protagonists which interact before and during the experiment. It also states their duties

  • Principal Investigator (PI): this is the person who submitted the proposal. His*her main duty is to organize the experiment design review. This means:
    • to prepare and hold a conceptual design report/review at least 2 months before the experiment starts,
    • to write and distributes the review minutes,
    • to prepare the list of people participating to the experiment and communicating it to the GSI.
  • GSI Contact Person: this person is someone who has already experience with PHELIX. In most case, it will be an employee of GSI or from the neighboring universities. His*her task is to tackle issues on a technical design side. In particular, he*she should be able to communicate with the PHELIX team to define the experimental parameters and laser configuration.
    • The GSI Contact Person is aware of the GSI policy regarding radiation safety. He*she will seek approval of the safety department of GSI SiSt before the experiment starts.
  • The experiment coordinator (EC). This person implements the experiment and executes the experiment plan alone or with the experimental team. His*her duties are the following:
    • The EC must plan to meet with the shot director (SD) at the beginning of every shift to discuss the shot plan for the day.
    • The EC is responsible for coordinating the activities of the experimental staff.
    • The EC orders the shots from the laser. Nobody else is allowed to do so.
    • The EC meets with the laser team everyday before the beamtime to communicate on the shot plan for the day.
    In general ECs cannot do two or more shifts in a row. An EC must also be capable of making decision concerning the experiment during his shift.
  • The shot director (SD). The shot director is organizing the shot sequence from the laser side in coordination with the EC. He*she can be reached at extension x2000 at any time during the beamtime. Shot directors are changed at every shift.
  • Target area responsible person: This person supports target area relevant work and provides local instructions regarding operation and safety.
    • Dennis Schumacher for the target area Z6 in the Experiment Hall
    • Bernhard Zielbauer for the target area in the Laserbay
    • Bernhard Zielbauer for the target area in the Laserlab