Hardware Hacking

I am currently building a Geiger–Müller Array with the aim of exploiting an effect called Electromagnetic Cascade or Particle shower as a means of significantly increasing the effective aperture and reducing other issues identified in my DIY experiments.

In a 1964 publication Bruno Rossi describes an experiment where cosmic rays could penetrate dense materials. Finding that cosmic radiation at sea level could penetrate over 1m of lead. In these same experiments he was also surprised to record a higher rate of detection, as many as 35 per hour as the thickness of lead increased peaking at 1.5cm and then falling slowly.

Shower curve obtained by Bruno Rossi’s experiment

Consequently it should be possible to build a dedicated Cosmic Ray (muon) detector where a number Geiger–Müller tubes in an array are encased within a lead block.

Prototype 1. Muon Detector using a Geiger–Müller tubes within Lead Block

The expected benefit using this method is that coincidence detection is moved into a horizontal arrangement which should greatly increase the aperture of the detector over conventional detectors while at the same time reduce terrestrial interference due to the shielding.

Prototype 1. Schematic of a basic two tube Geiger-Müller Coincidence Detector.

It should be mentioned at this stage that this idea is very much an experiment, however if muons do induce an Electromagnetic Cascade in Lead as demonstrated in other experiments there should be an improvement compared to using Geiger–Müller tubes on their own without lead shielding.