Forschungseinrichtung Linearbeschleuniger - Alvarez-Tank

Particle Accelerator

Lasertracker

Particle accelerators are research facilities at which basic research experiments are carried out. Further fields of research are medicine and materials research.

Particle accelerators are large devices in which charged particles are accelerated to high speeds by electric fields. Depending on the type of particle and accelerator, the accelerated particles reach almost the speed of light. A particle accelerator essentially consists of deflection and focusing magnets that direct the accelerated particle beam along a previously calculated path.

In a combination of linear accelerator and synchrotron, charged atomic nuclei are guided by magnetic fields in enormous vacuum tubes, accelerated to very high speeds and then shot at a metal foil. An analysis of the resulting "debris", the newly formed particles, provides new insights and insights into the structure of the investigated systems and the forces holding them together.


Customers:

GSI Helmholtz Centre for Heavy Ion Research GmbH

Heidelberg Ion Beam Therapy Centre (HIT)

Max Planck Institute for Nuclear Physics (MPIK) in Heidelberg

ANKA - the Synchrotron Radiation Facility at KIT

Deutsches Elektronen-Synchrotron - A Research Centre of the Helmholtz Association

Measurement Tasks

The "network measurement" is an old geodetic measuring principle in which neighbouring measuring points are "linked" by a multitude of measurements (usually direction and distance measurements). Network measurements are used in particular for very large or elongated measurement areas.

  • Measurement of small measuring ranges (up to approx. 30m) with Laser Tracker
  • Combined measurement of medium measuring ranges with laser tracker and precision leveller
  • Measurement of elongated measuring ranges (e.g. tunnel net) with precision total stations
  • Calculation of the measuring point coordinates by means of an adjustment procedure in which the measurements of the various measuring instruments are included.

Magnets can be up to a few meters long and weigh several tons. The exact positioning of the magnets with a tolerance of 0.1 mm to 0.2 mm is achieved with laser trackers and precision levels.

  • Measurement into the existing reference coordinate system
  • Measurement of the outer reference points (fiduciale points) in relation to the superordinate coordinate system
  • Adjustment to the specified nominal position, taking into account the different tolerances in the three component directions and orientations (rotations).
  • Stakeout of component positions

Experimental measurement involves the measurement of particle detectors relative to the beam axis of the accelerator.

  • Measuring the beam axis coordinate system
  • 6D Measurement of experimental components
  • Stakeout of superstructures
  • Adjustment of components within the experiment setup

Link: www.gsi.de/forschungbeschleuniger/forschung_an_overview/hades_experiment.htm

Accuracy of Measurement:

  • A few 1/10 mm over the entire system / network
  • 5/100 mm to 1/10 mm for individual assemblies
  • 1/10 mm to 2/10 mm for adjustments

Measuring Volume:

  • Local measurements (e.g. experiment setup) approx. 10 m x 5 m x 3 m
  • Small accelerator systems 50 m x 50 m x 5 m
  • Large accelerator facilities up to several kilometres (tunnel length)

Measuring principle:

  • Measurement of lengths, directions (angles) and height differences
  • Laser Tracker, Tachymeter
  • Precision Level

Method of Measurement

  • Overdetermined network measurement with different measuring devices
  • Best-Fit measurement over several measuring points
  • Free choice of position within the measuring area due to high-precision reference point field
  • Observance of the neighbourhood principle