The Use and Calibration of the Kern ME5000 Mekometer - SLAC ...

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INTRODUCTION
Wben it was introduced in 1986 the Kern ME5000 Mekometer immediately attracted attention from
the survey groups of accelerator laboratories around the world. This interest was generated not only
because the ‘ME5000 offered bigber accuracy than any other distance measuring instrument on -the
market, but also because, unlike previous instruments, its measuring range extended down to just a few
meters, thus opening up the wbole realm of accelerator housings to high-accuracy EDM measurements.
Abbougb Kern quoted a range of 20-8000 m, software was quickly made available to extend the
measurement range below 20 m (the PROMEKO program developed by the Technical University of
Munich).
In 1988-89 three DOE laboratories (CEBAF, FNAL and LBL) acquired instruments. ‘Since none of
these laboratories bad equipment to calibrate these instruments whereas SLAC did, extensive tests were
made witb all three instruments at SLAC in 1989.’ When four other laboratories initiated tbe
procurement process in tbe second half of 1991 to buy their own machines, plans were set in motion to
make a full series of test measurements with all DOE instruments, bringing them to SLAC one at a time.
Measurements commenced in January 1992 when the LBL, FNAL and CEBAF insmmrents were
measured in quick succession. Tbe ANL and BNL instruments, both new, followed in February and
March. In June SLAC received its own instrument and measurements began right away.
As what was to have been the culmination of this project, a workshop was held at SLAC in mid-June
to discuss tbe results. 16 people from 7 DOE laboratories attended as well as one representative from the
Pohang Light Source in Korea (see the list of participants on p. iv). By this time measurements were
complete for five instruments and mostly complete for a sixth (the SLAC instrument). This volume is the
for@ record of tbesix papers that were presented during the two days of the workshop. Tbe first paper
covers ME5000 Operation - how the instrument works. The second describes the measurements that were
made at SLAC with eacbinstrument. Data analysis is described in the third and fourth papers, and the
results are presented in the fifth paper. The final paper is a special invited paper commissioned from
Chris Curtis of CEBAF who spent three years (1987-89) working with a ME5000 on the Channel Tunnel
project in England.
The Workshop proved not to be tbe culmination of the project for two more instruments were
measured in August - the two SSC instruments. The workshop papers presented in this volume have heen
updated to incorporate these results. The baseline measurements for tbe SLAC instrument have not heen
completed and sufficient time has elapsed that they must be started afresh, something that is not feasible
in the next few months. These updated proceedings therefore represent the culmination of this project to
test tbe ME5000 instruments at use in each DOE laboratory.
SLAC
September 22,1992
’ T.W. Copeland-Davis, Can the Kern ME5000 Mekometa Replace Invar Measuremnts? Rcpulu
Machines, Procedings of the First Intemational Wonkshop on AccelcrtirAlignmmt, SLAC, July 31 - August 2, 1989, pp. 171-183.
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d Test ~mmnts witi l’hree