University of Wisconsin-Madison Physical Sciences Lab

Archive for February, 2017

View Through the Screen

Friday, February 3rd, 2017

In the building formerly known as the Synchrotron Radiation Center, PSL is building the newest neutrino detector for the Deep Underground Neutrino Experiment (DUNE). Rather than using the familiar photomultiplier tubes, like were used for the IceCube project, the DUNE project uses tiny wires wound around metal frames (Anode Panel Assembly or APAs) that are submerged in liquid argon at a temperature of -303 degrees F (or -185 degrees C). PSL, along with a lab in the United Kingdom, has been tasked with building the APAs.

Each APA consists of a stainless steel frame that is 20 feet long (6.3 meters), a layer of copper mesh, and 24 kilometers (almost 15 miles) of very thin copper beryllium wire wound around it. The wire is wound in four separate layers that are 1 cm apart. Due to the length of the wire, and number of wraps, it was too difficult to wind manually. PSL worked with a company to design a machine that would automatically wind the wires. Each wire is then soldered to a circuit board, with thousands of individual solder connections per APA.

We are building the first APA currently, and will be building two more, before shipping them to CERN for a small scale test.