The issue of laboratory bleaching in the infrared-radiofluorescence dating method

• Describes the behavior of K-feldspars during bleaching experiments.
• The bleaching level of an IR-RF signal is dependent on the wavelength and on exposure duration.
• Proposes suitable bleaching parameters adapted to IR-RF measurements.

Measuring the infrared radiofluorescence (IR-RF) signal is methodologically simpler than measuring the IRSL or TL signals. However, unlike classical luminescence measurements, the IR-RF signal is totally resetting when its highest value is reached. Previous studies (Buylaert et al., 2012; Trautmann et al., 2000) reported that the proper bleaching level of an IR-RF signal is difficult to define and seems to be dependent 1) on the wavelength used for bleaching and 2) on exposure duration. The IR-RF signals from K-feldspar samples have been measured with various bleaching wavelengths and exposure time using a Lexsyg research luminescence unit. In this study, we propose suitable bleaching parameters adapted to IR-RF measurements.