Building the Rotating Source Crossed Beams Apparatus

Peter Willis working on a Microstation Drawing of the Rotating Source Assembly.
Roughly 200 drawings were prepared over a period of about 1 year.

A contract was made with the Kurt J. Lesker Company to build the
rotating source and main chamber unit. Photo below shows the main
chamber (1200 lbs) on the vertical boring mill in Pittsburgh PA.  Wes Earnest
(left- project manager), reviews the progress of the operation.  Peter in foreground.

A closeup of the boring operation is shown below.  Dimensional tolerances
of the bore in the 2.5" thick stainless steel wall is critical, and was maintained
to 32.000 +/- 0.003" to ensure proper vacuum  seal to rotating source unit.

Peter and Hans lowering the precisely machined rotating ring
into the 32" OD bore of main chamber.  Sealing surfaces are
machined to mirror finish to facilitate rotary vacuum seal using
two spring-loaded teflon seals.

The detector and most of the additional components were done by the
Physics machine shop here at Cornell.  The photo below shows the
1" thick stainless steel plate of the detector on the milling machine.
Plate is machined with keying surfaces to align into main chamber to tolerances of 0.002"

Trial fit of the detector unit in the main chamber (below).
Nate on left;  Jeff and Peter on right


Rotating source unit shown below with Brian, Peter and Hans behind.
View is looking into molecular beam source.

The completed apparatus is shown below with Peter and Ryan on the left.
A 157 nm excimer laser (upper right) is used for single photon ionization
of reaction products in the detector, located about 25 cm from the collision region.

Below is a picture of Hans and Peter beside the machine.  Yes, those are
green leaves on the trees outside the window of our lab!

Back to Davis Group Homepage
You are visitor number        to this page since April 16, 2000.