Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Thermoluminescence (TL) of NaF:Ca<jats:sup>2+</jats:sup> single crystals after room‐temperature γ‐ray irradiation exhibits six glow peaks at 75, 114, 128, 160, 240, and 290 °C. The 75 and 240 °C peaks are assigned to hole centres; the 114 and 290 °C peaks are attributed to F<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-inf-1.gif" xlink:title="urn:x-wiley:03701972:media:PSSB2221120219:tex2gif-inf-1" /> and F centres, respectively. Involvement of Ca<jats:sup>2+</jats:sup> aggregates is suggested in the origin of the 160 °C peak. The origin of the 128 °C peak is explained by assuming the presence of di‐interstitials. It is inferred that F<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-inf-3.gif" xlink:title="urn:x-wiley:03701972:media:PSSB2221120219:tex2gif-inf-3" /> centres are created, even prior to optical bleaching of F centres, to some extent during γ‐ray irradiation. It is also found that on re‐irradiation of the samples containing F<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-inf-5.gif" xlink:title="urn:x-wiley:03701972:media:PSSB2221120219:tex2gif-inf-5" /> centres, these F<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-inf-7.gif" xlink:title="urn:x-wiley:03701972:media:PSSB2221120219:tex2gif-inf-7" /> centres are destroyed. TL spectra show two bands at 420 to 450 and 580 nm. Photoluminescence spectra also show two bands at 450 and 580 nm.</jats:p>