Polyethylene terephthalate polymers at mountain altitude as cosmic ray heavy particle detector

Abstract

We exposed a stack of polyethylene terephthalate (PET) detectors each of thickness I 100 mu m with an area of 21 cm x 30cm along with a separate stack of the standard solid state nuclear track detector (SSNTD) CR-39 (Intercast Europe Co., Italy) of thickness 630 mu m and area 20cm x 24cm at Darjeeling, India in the Eastern Himalayan Range, under an atmospheric pressure of 765 hPa. The SSNTDs were kept horizontally in the open air for similar to 1.5 x 10(7) s. After etching the PET detectors in 6.25N NaOH solution at 55 +/-0.1 degrees C, and partial scanning, it is found that the PET detectors recorded 188 particle tracks of near normal incidence within an area similar to 0.37cm(2). The observed flux being similar to 10(-5)/(cm(2) s sr) we have tried to explain our observation on PET detector vis-a-vis the tracks recorded in CR39 exposed simultaneously under similar conditions.