Cosmic Array for Splash Adelaide 2017 Winter


The aim of this project is to deploy 16 individual cosmic ray detectors on the Elder Park foreshore in Adelaide. This is a part of the Splash Adelaide 2017 Winter Festival and is built in collaboration with a group of artist-musicians called
Sacred Resonance.

Proposed Location on the Elder Park foreshore

When the public comes to visit this installation, they will experience how cosmic rays are all around us and arrive in showers of particles. Each detector will seem to randomly twinkle with colours and sounds that are triggered by cosmic rays. The experience will be not unlike walking through a maze of colourful wind chimes.

However, as cosmic rays arrive in showers of particles, some of these detectors will trigger in unison and others randomly.  A similar experience to what can be witnessed in nature like the sounds of Cicadas or the flashing light of Fireflies, where both sound and light fade in and out from randomness into unison.

Cosmic Rays have been present throughout the entire evolutionary history of life on our planet and so this display reinforces our connection with the universe and the importance of science and understanding the natural world.

However, the project has no agenda other than the first of what I hope are thought-provoking art/science installations.  Which will provide an interesting window into the universe and the natural world around us, leaving the observer to form their own connections and conclusions.

Technical
Each detector in the array will produce a bright flash of one of 4 colours (red, green, blue or white). In the same manner, one of 3 musical notes ( e.g. C, F, G or other notes) or all 3 notes together depending on the direction and angle of an ionising particle called a muon passes through two or more Geiger–Müller tubes simultaneously.  

Music samples are currently being developed by Darren Curits a musician at Sacred Resonance.

The system used for playing sounds and other IoT functions utilises the latest Raspberry Pi Zero W and the code for this has been developed by Paul Schulz.

Working demonstration prototype.

A rough demonstration of light and sound using a current prototype 

Overview block diagram of operation includes

Circuit diagram of the central detector

PCB Layout of the central detector 96.5mm X 63.5mm

Raspberry Pi Zero W pinout

A note about: Geiger–Müller Tubes
I’ve had comments regarding the validity of using Geiger–Müller Tubes for a cosmic ray (muon) detector. Pointing out that Photomultipliers and scintillation panels are best, and yes the are far more effective. However, they are also expensive, whereas Geiger–Müller tubes are relatively cheap and easily available to purchase.

Although I’m currently working on a solid-state detector there are a few issues yet to overcome, so this is still a few months away.

History is full of examples of physicists using Geiger–Müller tubes for cosmic ray observations up to the 80s. Geiger Tube Telescopes (GTT) were used by NASA including many Pioneer spacecraft missions and others. One most notable user was Bruno Benedetto Rossi a famous Italian experimental physicist who made major contributions to particle physics and the study of cosmic rays. At the age of 24, he fabricated his own Cosmic Ray detector using Geiger–Müller tubes and then went on to invent the first practical electronic coincident circuit.