It is measured the effect of magnetic fields on the scintillation of tetracene‐doped anthracene crystals under α‐particle bombardment. Comparing the data with results obtained under photo‐excitation yields a lower bound for the average triplet exciton density in an α‐particle track. The present calculated value of 3 × 1017 triplets cm−3 is in good agreement with a previous estimate of 1018 cm−3 for pure tetracene. It is also shown that under α‐particle bombardment, because of the high triplet exciton density, heterofusion of a free anthracene triplet exciton with a trapped tetracene triplet is not an important channel for producing scintillation. Instead, most of the green tetracene scintillation arises from the trapping of anthracene singlet excitons, which in turn are produced by the homofusion of host triplets.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics