The Mirror Machine

Author: Brian, Jay, Jimbo, Luke, Scott & Tim

Motivated to debut something cool at our group's annual social event, High Voltage Weekend - Summer 2019, coupled with the acquisition of some old electromagnet parts and vacuum system hardware, we built a demonstration mirror machine. This machine is for the instructional experimentation of linear plasma confinement devices.

The following photos step through the acquisition, construction, and operation of this demonstration device. It will improve over time, and several research ideas have been proposed using this or a variant of this machine.

The completed demo device.

The million dollar shot: a beautiful demonstration of the "Magnetic Bottle."

The following photos document the journey to making this machine:

We acquired an old double magnet ion beam spectrometer, and stripped it for the four identical coils.

The top pair were easy to remove. Each coil weighs about 100lbs.

The four coils cleaned up and on the bench for testing.

10-inch ID, 15.75inch OD.

First powered testing, each coil has a DC resistance of about 0.25 ohms.

A quick measurement of the axial field in the mid plane of two coils separated by about 3 inches.

700 Gauss

Without water cooling the coils do warm up quickly.

Meanwhile Jay was busy making adjustable cradles for the coils

The device is starting to take shape.

A good eBay deal on #2 cable 3/8-inch crimp on lugs.

An even better eBay deal was the hydraulic crimper - less than $30, and it works.

A very nice crimp!

Next was the water cooling lines.

A temperature profile of the system, outer two coils energized only.

First plasma - just air.

Neon and Scott operating.

A Neon plasma with identical current in each coil.

Jimbo looking at the lines of Neon in a grating spectrograph.

Finally Neon with the longitudinally adjusted magnetic fields to create the magnetic mirror.