7/28/06: This is all very old stuff. It remains here only for archival purposes.

10/07/02: Collimators were removed and reinstalled during the summer of 2002. New survey measurement results are available. Click here

10/10/00: New survey measurement results are now available see: http://hallaweb.jlab.org/news/minutes/sieves_2000.htm

Latest best Old estimate of target to collimator/sieve distance.

(from survey reports 483r and 359)

3/17/99 -JJL

Electron Large Collimator

Electron Sieve

Hadron Large Collimator

Hadron Sieve






2 mm






For a discussion of the present status of the sieve offsets see: http://hallaweb.jlab.org/news/minutes/sieves_2000.htm

Older information can still be found at: http://hallaweb.jlab.org/news/minutes/sieve-offsets.html

Please send comments or questions to John LeRose: lerose@jlab.org

Return to Hall A homepage