The a-value of polymineral fine grain samples measured with the post-IR IRSL protocol

• Verfasst von: Kreutzer, Sebastian [VerfasserIn]
• Verfasst von: Schmidt, Christoph [VerfasserIn]
• Verfasst von: DeWitt, Regina [VerfasserIn]
• Verfasst von: Fuchs, Markus [VerfasserIn]
• Titel: The a-value of polymineral fine grain samples measured with the post-IR IRSL protocol
• Verf.angabe: Sebastian Kreutzer, Christoph Schmidt, Regina DeWitt, Markus Fuchs
• E-Jahr: 2014
• Jahr: October 2014
• Umfang: 12 S.
• Illustrationen: Diagramme
• Fussnoten: Online veröffentlicht: 30. Juni 2014 ; Gesehen am 01.04.2025
• Titel Quelle: Enthalten in: Radiation measurements
• Ort Quelle: Amsterdam [u.a.] : Elsevier Science, 1994
• Jahr Quelle: 2014
• Band/Heft Quelle: 69(2014) vom: Okt., Seite 18-29
• ISSN Quelle: 1879-0925
• DOI: doi:10.1016/j.radmeas.2014.04.027
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: -value
• Sach-SW: Fine grain
• Sach-SW: Loess
• Sach-SW: Luminescence dating
• Sach-SW: Polymineral
• Sach-SW: post-IR IRSL
• Sach-SW: α-efficiency
• K10plus-PPN: 192092017X

Abstract

Recent post-IR IRSL (pIRIR) dating studies using polymineral fine grains assumed that the a-values obtained for the IRSL signal at 50 °C and the pIRIR signal at higher temperatures (e.g. 225 °C) are identical. However, the a-value of a sample depends on the stimulation method, and the assumption mentioned above remains to be tested. Using five polymineral fine grain samples, this study investigates whether a common a-value can be used for both the IR and the pIRIR signals. Applying the pIRIR protocol, the a-values were measured with three different methods of signal resetting (optical bleaching, end of SAR cycle, heating). In addition, uncorrected α- and β-irradiation induced growth curves were determined for three samples and fitted with single saturating exponential functions. For the investigated samples we found significant mean differences, 0.023 ± 0.012 and higher, in the a-values determined for the IR50 and pIRIR225 signals. Synthetic a-values deduced from uncorrected multiple-aliquot dose response curves seem to confirm this observation. Although, in summary, our results indicate that the practice of using a common a-value should be carefully re-considered, the physical reasons remain to be determined.