Determination of the detection threshold for Polyethylene Terephthalate (PET) Nuclear Track Detector (NTD)

In this work we investigated the detection threshold of the polymer material Polyethylene Terephthalate (PET) intended to be used as Nuclear Track Detector (NTD) in the search for rare events (e.g. strangelets) in cosmic rays. 11 MeV 12C and 2 MeV proton beams from the accelerator at the Institute of Physics (IOP), Bhubaneswar were utilized for this study. The results show that the PET detector has a much higher detection threshold (Z/β∼140Z/β∼140) compared to many other commercially available and widely used detector materials like CR-39 (Z/β∼6–20Z/β∼6–20) or Makrofol (Z/β∼57Z/β∼57). This makes PET a particularly suitable detector material for testing certain phenomenological models which predict the presence of strangelets as low energy, heavily ionizing particles in cosmic radiation at high mountain altitudes.