Programming the data-acquisition and RF control hardware for RF tests
of ILC cavities
Mentor: Bill Ashmanskas

The proposed International Linear Collider (ILC) will allow particle
physicists to study collisions between electrons and positrons at a
new energy frontier, addressing some of the most fundamental questions
about the nature of matter, energy, space, and time.  To build the
ILC, scientists will need to fabricate and to test many thousands of
niobium Superconducting Radio Frequency (SRF) cavities.  Scientists at
laboratories around the world, including Cornell, are now working to
develop the procedures for this fabrication and testing.

Cornell's SRF lab is one of only a few existing facilities in the US
for performing Radio Frequency tests, at 2 degrees Kelvin, of
superconducting niobium resonant cavities.  In these tests, one
applies RF waveforms of a range of amplitudes and observes the power
at several points in the test circuit, to map out the resonator
quality factor (Q) of a cavity vs. accelerating field (E).

The control system now in use for cavity RF tests requires a human
operator to turn knobs manually on archaic modules and to read power
levels visually from oscilloscopes and meters, typing values into a
spreadsheet.  By setting up and suitably programming some new digital
electronics modules already developed by Prof. Liepe at Cornell, we
can streamline these cavity tests, so that they are done more quickly,
more accurately, and with less risk of human error.  We may also be
able to perform more measurements (e.g. collecting data from several
resonant modes of each cavity) with the helium available for a given
test.

The student will gain programming and data-acquisition experience,
which is a generally useful skill for many fields of experimental
science.  He or she may also participate in some tests of ILC
cavities, which will be of interest for students considering graduate
study in accelerator physics or experimental particle physics.