Aluminium Mirrors: An Alternative for Ground Based Cherenkov Telescopes

We present a novel alternative to the use of glass mirrors on ground based Cherenkov telescopes. Glass mirrors, whilst having excellent imaging characteristics, can become a limiting factor in the design of such telescopes, due to their weight and expense. We produce mirrors using an innovative vacuum forming process (global patent applied for), using only aluminium materials. The result is a mirror weighing and costing a fraction of that of a glass mirror. The method of production is described together with preliminary results of the shape conformity and reproducibility. The properties of the reflective surface are outlined, including robustness and specular reflectivity. This is shown to be superior to its glass equivalent particularly at wavelengths relevant to Cherenkov radiation.