Pion Beta Beamtube and Active Degrader


You will find the originally designed beamtube ('nosepiece') drawing on The Detector Handbook Page. The beamtime 1998 analysis showed out, that a new design of the beamtube is necessary. The reason is nuclear reactions of the pions inside of the beamtube walls. This will produce backgound events which are a problem for our measurement. The new beamtube will be shorter (about 400 mm distance to the target center).

This means, that we have to get a new support structure for our Active Degrader (AD), which is just in front of our target and which was originally attached to the nosepiece.

We want to fix this AD to a distance ring between our cylindrical MWPC.

The next two drawings show, how it should look like:

Active Degrader Support Structure

AD support ring

new beamtube

new beamtube 2
  The mechanical support structure for the degrader is built. On the following pictures you will see it:

Degrader Support Structure

Degrader Support Structure

Now it is attached to the chamber distance ring:

AD built in

  Send a mail to the author

H.P. Wirtz , 30-Mar-1999
last update:  08-Apr-1999

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