Measuring the infrared stimulated luminescence (IRSL) of K-feldspar or polymineral separates at elevated temperatures (>150°C) after initial IRSL stimulation at 50°C (IRSL50) has gained considerable popularity for estimating the equivalent dose (
Commonly, either sand-sized (~90–250 μm) K-feldspar or silt-sized (~4–11 μm) polymineral grains are prepared for pIRIR measurements. While it is debatable whether the coarse grain size fraction should be HF-etched to remove the outer layer influenced by external α-radiation (e.g., Duller, 1992; Li and Li, 2011; Trauerstein
Compared to the vast body of literature published during the past years on the application of the pIRIR protocol to various sedimentary archives, only relatively few studies determined the
identifying a suitable method to accurately determine pIRIR investigating whether there is a common pIRIR290 clarifying whether the pIRIR290
Many samples in our laboratories were recently measured with a distinct IRSL protocol (following the approach described in detail in Faust
To evaluate both the variability of the pIRIR290
Summary of investigated samples. Sample codes BT… refer to the luminescence laboratory in Bayreuth, codes C-L… to the laboratory in Cologne; pIRIR290 = post-IR IRSL protocol with 290°C stimulation temperature (following Thiel et al., 2011); IRSLF = IRSL protocol according to Faust et al. (2015); MAAD = multiple-aliquot additive-dose protocol applied both to the pIRIR290 and the IRSLF emission (see main text for further details).Sample code Provenance Coordinates Depositional environment Applied protocols Reference BT1257 Titel, Serbia 45°17′42″N, 20°11′22″E Loess PIRIR290 – BT1258 Titel, Serbia 45°17′42″N, 20°11′22″E Loess PIRIR290 – BT1259 Titel, Serbia 45°17′42″N, 20°11′22″E Loess PIRIR290 – BT1337 Encantado I, Fuerteventura 28°38′20″N, 13°58′37″W Aeolian deposits IRSLF – BT1339 Encantado I, Fuerteventura 28°38′18″N, 13°58′40″W Aeolian deposits IRSLF – BT1340 Melian, Fuerteventura 28°40′18″N, 13°57′08″W Aeolian deposits IRSLF Roettig BT1341 Melian, Fuerteventura 28°40′18″N, 13°57′08″W Aeolian deposits IRSLF Roettig BT1342 Melian, Fuerteventura 28°40′09″N, 13°57′14″W Aeolian deposits IRSLF Roettig BT1343 Melian, Fuerteventura 28°40′09″N, 13°57′14″W Aeolian deposits IRSLF Roettig BT1344 Melian, Fuerteventura 28°40′22″N, 13°57′12″W Aeolian deposits MAAD (PIRIR290, IRSLF) Roettig BT1345 Melian, Fuerteventura 28°40′22″N, 13°57′12″W Aeolian deposits MAAD (PIRIR290, IRSLF) Roettig BT1421 Encantado III, Fuerteventura 28°38′21″N, 13°58′44″W Aeolian deposits IRSLF Roettig BT1423 Encantado III, Fuerteventura 28°38′21″N, 13°58′44″W Aeolian deposits IRSLF Roettig BT1424 Encantado III, Fuerteventura 28°38′21″N, 13°58′44″W Aeolian deposits IRSLF Roettig BT1425 Encantado III, Fuerteventura 28°38′21″N, 13°58′44″W Aeolian deposits IRSLF Roettig BT1426 Encantado III, Fuerteventura 28°38′21″N, 13°58′44″W Aeolian deposits IRSLF Roettig BT1432 Enamorados, Fuerteventura 28°38′05″N, 13°59′06″W Aeolian deposits IRSLF – BT1513 Jable 1, Fuerteventura 28°38′38″N, 13°58′28″W Aeolian deposits PIRIR290, IRSLF – BT1514 Jable 1, Fuerteventura 28°38′38″N, 13°58′28″W Aeolian deposits IRSLF Roettig BT1515 Jable 1, Fuerteventura 28°38′38″N, 13°58′28″W Aeolian deposits PIRIR290, IRSLF Roettig BT1517 Jable 1, Fuerteventura 28°38′38″N, 13°58′28″W Aeolian deposits PIRIR290, IRSLF – BT1519 Fuerteventura, Spain 28°39′09″N, 13°57′27″W Aeolian deposits PIRIR290, IRSLF – BT1525 Jable 2, Fuerteventura 28°38′50″N, 13°58′38″W Aeolian deposits PIRIR290, IRSLF Roettig BT1528 Jable 2, Fuerteventura 28°38′50″N, 13°58′38″W Aeolian deposits PIRIR290, IRSLF – BT1529 Montana Roja, Fuerteventura 28°38′59″N, 13°51′08″W Aeolian deposits IRSLF – BT1401 Eifel, Germany 50°04′39″N, 07°01′43″E Quartzitic slate PIRIR290 Schmidt BT1415 Vârghis, Romania 46°12′58″N, 25°32′36″E Aeolian cave deposit PIRIR290 Veres BT1416 Vârghis, Romania 46°12′58″N, 25°32′36″E Aeolian cave deposit PIRIR290 Veres BT1417 întorsura Buzăului, Romania 45°43′02″N, 26°04′13″E Loamy hillslope deposit PIRIR290 – C-L3704 Urluia, Romania 44°05′42″N, 27°54′07″E Loess PIRIR290 – C-L3707 Urluia, Romania 44°05′42″N, 27°54′07″E Loess PIRIR290 Obreht C-L3778 Stalać, Serbia 43°40′39″N, 21°25′04″E Loess PIRIR290 Bösken C-L3780 Stalać, Serbia 43°40′39″N, 21°25′04″E Loess PIRIR290 Bösken C-L3784 Stalać, Serbia 43°40′39″N, 21°25′04″E Loess PIRIR290 Bösken C-L3786 Stalać, Serbia 43°40′39″N, 21°25′04″E Loess PIRIR290 Bösken C-L3787 Stalać, Serbia 43°40′39″N, 21°25′04″E Pedogenetically overprinted loess PIRIR290 Bösken C-L3788 Stalać, Serbia 43°40′39″N, 21°25′04″E Loess PIRIR290 Bösken C-L4029 Vrsac, Serbia 45°09′10″N, 21°09′30″E Lacustrine sediment PIRIR290 Zeeden C-L4030 Vrsac, Serbia 45°09′10″N, 21°09′30″E Lacustrine sediment PIRIR290 Zeeden C-L4031 Vrsac, Serbia 45°09′10″N, 21°09′30″E Lacustrine sediment PIRIR290 Zeeden C-L3789 Ságvár, Hungary 46°49′18″N, 18°05′23″E Loess PIRIR290 Bösken C-L3791 Ságvár, Hungary 46°49′18″N, 18°05′23″E Loess PIRIR290 Bösken C-L3792 Ságvár, Hungary 46°49′18″N, 18°05′23″E Loess PIRIR290 Bösken C-L3793 Ságvár, Hungary 46°49′18″N, 18°05′23″E Loess PIRIR290 Bösken C-L3795 Bodrogkeresztúr, Hungary 48°08′50″N, 21°21′48″E Loess PIRIR290 Bösken C-L3797 Bodrogkeresztúr, Hungary 48°08′50″N, 21°21′48″E Pedogenetically overprinted loess PIRIR290 Bösken C-L3799 Bodrogkeresztúr, Hungary 48°08′50″N, 21°21′48″E Loess PIRIR290 Bösken
Prior to measurement, samples were dry or wet sieved to grain sizes <63 μm, soaked in 10% HCl and 10% H2O2 to dissolve carbonates and oxidise organic matter, respectively, treated with 0.01 N sodium oxalate to disperse aggregates (only Cologne laboratory) and subsequently settled in a water column for distinct periods to extract the target grain size range of ~4–11 μm (application of Stokes’ Law). All steps were carried out under subdued red light conditions (640 ± 20 nm). Readily prepared fine grains were pipetted onto aluminium or steel discs (~2 mg per aliquot in Bayreuth, ~0.9–1.0 mg in Cologne) for IRSL and pIRIR measurements. Experiments by Kreutzer
All measurements were carried out on Risø TL/OSL DA15/DA20 readers, equipped with infrared (875 ± 80 nm) diodes for signal stimulation and an EMI 9235QB15 photomultiplier tube coupled with a Chroma D410/30x band pass filter (410 ± 15 nm) for signal discrimination and detection. Artificial β-irradiation was carried out with a built-in 90Sr/90Y β-source delivering dose rates to fine grains between 0.040 ± 0.002 and 0.133 ± 0.005 Gy s–1. In Bayreuth, α-irradiation was conducted in vacuum (<10–2 mbar) using either the built-in 241Am source (0.144 ± 0.007 Gy s–1) of one of the Risø readers or an external six-seater Littlemore 241Am irradiation facility (type 721/B) with a dose rate of 0.021 ± 0.002 Gy s–1. In Cologne, the built-in α-source of a Freiberg Instruments lexsyg research reader was used for that purpose (0.197 ± 0.004 Gy s–1, <1 mbar). Information on the calibration of these α-sources is given in the appendix.
Acquired luminescence data were analysed using the program Analyst (v.4.31.9; Duller, 2015). IRSL and pIRIR290 decay curves were measured for 300 s (Bayreuth) or 200 s (Cologne) in this study, and the initial 5 s were integrated to give the signal with which dose response curves were constructed. Instrumental background averaged from the last ~40 s of the decay curve was subtracted from the integrated signal.
Previous studies on the appropriateness of using single-aliquot regeneration (SAR) protocols for
Fig. 1
Results of MAAD measurements for sample BT1345 (IRSLF protocol). The corresponding a-value is shown in Table 4.

Measurement protocols employed for a-value determination. Step 1 in the first SAR cycle is carried out using α-irradiation, while all subsequent irradiations refer to β-doses. The pIRIR290 protocol follows Thiel et al. (2011), while the IRSLF protocol was adopted from Faust et al. (2015). Stimulation times for IRSL50 and pIRIR290 signals were 300 s (Bayreuth) or 200 s (Cologne); an IRSL readout at 325°C for 600 s (Bayreuth) or 200 s (Cologne) intended to fully zero IRSL traps prior to the next regeneration cycle.pIRIR290 IRSLF Step Procedure Signal Step Procedure Signal 0 Resetting of the natural signal 0 Resetting of the natural signal 1 Irradiation with dose 1 Irradiation with dose 2 Preheat (320°C, 60 s) 2 Preheat (270°C, 120 s) 3 IR stimulation (50°C, 300 s or 200 s) 3 Pause (1200 s) 4 IR stimulation (290°C, 300 s or 200 s) 4 IR stimulation (125°C, 300 s) 5 Irradiation with test dose 5 Irradiation with test dose 6 Preheat (320°C, 60 s) 6 Preheat (270°C, 120 s) 7 IR stimulation (50°C, 300 s or 200 s) 7 Pause (1200 s) 8 IR stimulation (290°C, 300 s or 200 s) 8 IR stimulation (125°C, 300 s) 9 IR stimulation (325°C, 600 s or 200 s) 9 Return to step 1 10 Return to step 1
Relative change of the Lα/Tβ ratio after repeated Lα – Tβ cycles (see main text for further information).Sample BT1258 BT1259 Protocol IRSLF PIRIR290 IRSLF plRIR290 3 cycles 6% 3% 9% 8% 7 cycles 5% 7% 12% 13%
Results of a-value determination. In contrast to Sample code Protocol Resetting α-dose (Gy) Δ SD (1 BT1257 pIRIR290 Hot bleach 298 4 0.078 0.005 0.005 BT1258 pIRIR290 Hot bleach 298 4 0.087 0.005 0.008 BT1259 pIRIR290 Hot bleach 298 4 0.083 0.004 0.007 BT1344 pIRIR290 Hot bleach 298 4 0.084 0.006 0.009 BT1344 pIRIR290 MAAD Hot bleach – – 0.035 0.004 – BT1345 pIRIR290 Hot bleach 633 4 0.102 0.009 0.011 BT1345 pIRIR290 MAAD Hot bleach – – 0.075 0.008 – BT1513 pIRIR290 Hot bleach 298 3 0.089 0.005 0.006 BT1515 pIRIR290 Hot bleach 298 3 0.077 0.009 0.010 BT1517 pIRIR290 Hot bleach 298 3 0.076 0.003 0.003 BT1519 pIRIR290 Hot bleach 298 3 0.071 0.005 0.003 BT1525 pIRIR290 Hot bleach 298 3 0.094 0.008 0.011 BT1526 pIRIR290 Hot bleach 298 3 0.107 0.008 0.004 BT1527 pIRIR290 Hot bleach 298 3 0.090 0.010 0.006 BT1528 pIRIR290 Hot bleach 298 3 0.075 0.004 0.007 BT1401 pIRIR290 Hot bleach 373 2 0.091 0.008 0.008 BT1415 pIRIR290 Hot bleach 298 4 0.085 0.004 0.006 BT1416 pIRIR290 Hot bleach 298 4 0.083 0.003 0.003 BT1417 pIRIR290 Hot bleach 298 4 0.091 0.004 0.007 C-L3704 pIRIR290 Annealing 79 2 0.109 0.006 0.009 C-L3707 pIRIR290 Annealing 79 2 0.115 0.006 0.008 C-L3778 pIRIR290 Annealing 79 3 0.116 0.006 0.010 C-L3780 pIRIR290 Annealing 79 2 0.108 0.007 0.015 C-L3784 pIRIR290 Annealing 79 3 0.119 0.010 0.016 C-L3786 pIRIR290 Annealing 79 2 0.085 0.006 0.009 C-L3787 pIRIR290 Hot bleach 197 1 0.078 0.007 – C-L3787 pIRIR290 Annealing 394 6 0.084 0.003 0.016 C-L3788 pIRIR290 Annealing 394 6 0.105 0.004 0.010 C-L3789 (50C) pIRIR290 Annealing 79 3 0.103 0.007 0.012 C-L3789 (80C) pIRIR290 Hot bleach 197 3 0.109 0.006 0.017 C-L3789 (80C) pIRIR290 Annealing 296 11 0.074 0.003 0.009 C-L3791 pIRIR290 Annealing 394 6 0.084 0.003 0.016 C-L3792 pIRIR290 Annealing 394 5 0.091 0.004 0.016 C-L3793 pIRIR290 Hot bleach 197 2 0.100 0.004 0.005 C-L3793 pIRIR290 Annealing 394 6 0.089 0.003 0.020 C-L3795 pIRIR290 Annealing 394 5 0.107 0.004 0.005 C-L3797 pIRIR290 Annealing 394 6 0.100 0.004 0.005 C-L3799 pIRIR290 Annealing 394 3 0.096 0.004 0.007 C-L4029 pIRIR290 Hot bleach 50 5 0.113 0.009 0.010 C-L4030 pIRIR290 Hot bleach 50 5 0.120 0.012 0.010 C-L4031 pIRIR290 Hot bleach 50 5 0.115 0.010 0.019 BT1337 IRSLF Hot bleach 199 4 0.077 0.014 0.005 IRSLF Hot bleach 199 4 0.074 0.003 0.003 BT1340 IRSLF Hot bleach 199 4 0.096 0.009 0.002 BT1341 IRSLF Hot bleach 199 4 0.099 0.014 0.007 BT1342 IRSLF Hot bleach 199 4 0.086 0.010 0.008 BT1343 IRSLF Hot bleach 199 4 0.078 0.003 0.003 BT1344 IRSLF Hot bleach 199 4 0.091 0.006 0.005 BT1344 IRSLF MAAD Hot bleach – – 0.079 0.006 – BT1345 IRSLF Hot bleach 199 4 0.085 0.007 0.003 BT1345 IRSLF MAAD Hot bleach – – 0.069 0.004 –
Despite the fact that
The determination of the
A common SAR procedure to determine the
Fig. 2
Comparison of a-values determined following different luminescence signal resetting modes. Each data point represents 2–4 individual a-value measurements; the error bars show the standard deviation. All measurements were carried out with aliquots of ~1 mg sample material, except for BT1344* (~2 mg sample material per aliquot).

One basic assumption of SAR protocols is that the luminescence signal of a test dose measurement monitors the sample’s luminescence sensitivity to the preceding regenerative β-dose (e.g., Murray and Wintle, 2000). Whether this assumption holds true for an α-regenerated signal that is monitored by a β-test dose measurement is, however, unclear. Accurate sensitivity correction can be expected if the α-induced luminescence signal (
We therefore measured repeated
Fig. 3
Results of the repeated

As evident from
Since the SAR approach as outlined in the previous sections appears to be appropriate for α-efficiency determination for the majority of polymineral samples, we employed it to determine the
Fig. 4
Graphical summary of PIRIR290 and IRSLF a-values measured in Bayreuth and Cologne. The dashed lines indicate the unweighted average and its standard deviation (1

The
Fig. 5
Boxplot of PIRIR290 a-values grouped according to sampled outcrops. Further sampling information and numerical results are given in Tables 1 and 4.

To investigate whether pIRIR290
Results of these five samples are shown in
Fig. 6
Results of comparative a-value measurements between the two involved laboratories. Data points represent 2–6 aliquots and are plotted along with the respective standard deviation.

Comparative measurements of sample BT1344 in Cologne using aliquot sizes of ~1.0 and ~2.0 mg yielded identical
In order to further study the potential reasons for differing
Fig. 7
Equivalent doses determined with the pIRIR protocol at varying reading temperatures (270, 290, 310°C). Further technical details are given in the main text. A comparative dose estimate derived in the Cologne laboratory using the pIRIR290 protocol is indicated with open symbols. Error bars represent the standard deviation of contributing aliquots.

Our experiments on the correction of sensitivity changes induced by an α-regeneration dose by means of a β-test dose indicate that for the majority of the investigated samples the SAR protocol (recovery of a known α-dose with β-SAR cycles) is suitable to determine reliable
The assessment whether or not there is a common
The slight differences in the pIRIR290 measurement protocol (cf.
Contrasting the
The study of Kreutzer
Taken previous and the current data together, the
The analyses conducted in the frame of
The SAR protocol appears to be appropriate for determining IRSL Within one laboratory environment Determining a common and accurate Measurement equipment seems to exert significant influence on For the samples investigated, the
Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Summary of investigated samples. Sample codes BT… refer to the luminescence laboratory in Bayreuth, codes C-L… to the laboratory in Cologne; pIRIR290 = post-IR IRSL protocol with 290°C stimulation temperature (following Thiel et al., 2011); IRSLF = IRSL protocol according to Faust et al. (2015); MAAD = multiple-aliquot additive-dose protocol applied both to the pIRIR290 and the IRSLF emission (see main text for further details).
Sample code | Provenance | Coordinates | Depositional environment | Applied protocols | Reference |
---|---|---|---|---|---|
BT1257 | Titel, Serbia | 45°17′42″N, 20°11′22″E | Loess | PIRIR290 | – |
BT1258 | Titel, Serbia | 45°17′42″N, 20°11′22″E | Loess | PIRIR290 | – |
BT1259 | Titel, Serbia | 45°17′42″N, 20°11′22″E | Loess | PIRIR290 | – |
BT1337 | Encantado I, Fuerteventura | 28°38′20″N, 13°58′37″W | Aeolian deposits | IRSLF | – |
BT1339 | Encantado I, Fuerteventura | 28°38′18″N, 13°58′40″W | Aeolian deposits | IRSLF | – |
BT1340 | Melian, Fuerteventura | 28°40′18″N, 13°57′08″W | Aeolian deposits | IRSLF | |
BT1341 | Melian, Fuerteventura | 28°40′18″N, 13°57′08″W | Aeolian deposits | IRSLF | |
BT1342 | Melian, Fuerteventura | 28°40′09″N, 13°57′14″W | Aeolian deposits | IRSLF | |
BT1343 | Melian, Fuerteventura | 28°40′09″N, 13°57′14″W | Aeolian deposits | IRSLF | |
BT1344 | Melian, Fuerteventura | 28°40′22″N, 13°57′12″W | Aeolian deposits | MAAD (PIRIR290, IRSLF) | |
BT1345 | Melian, Fuerteventura | 28°40′22″N, 13°57′12″W | Aeolian deposits | MAAD (PIRIR290, IRSLF) | |
BT1421 | Encantado III, Fuerteventura | 28°38′21″N, 13°58′44″W | Aeolian deposits | IRSLF | |
BT1423 | Encantado III, Fuerteventura | 28°38′21″N, 13°58′44″W | Aeolian deposits | IRSLF | |
BT1424 | Encantado III, Fuerteventura | 28°38′21″N, 13°58′44″W | Aeolian deposits | IRSLF | |
BT1425 | Encantado III, Fuerteventura | 28°38′21″N, 13°58′44″W | Aeolian deposits | IRSLF | |
BT1426 | Encantado III, Fuerteventura | 28°38′21″N, 13°58′44″W | Aeolian deposits | IRSLF | |
BT1432 | Enamorados, Fuerteventura | 28°38′05″N, 13°59′06″W | Aeolian deposits | IRSLF | – |
BT1513 | Jable 1, Fuerteventura | 28°38′38″N, 13°58′28″W | Aeolian deposits | PIRIR290, IRSLF | – |
BT1514 | Jable 1, Fuerteventura | 28°38′38″N, 13°58′28″W | Aeolian deposits | IRSLF | |
BT1515 | Jable 1, Fuerteventura | 28°38′38″N, 13°58′28″W | Aeolian deposits | PIRIR290, IRSLF | |
BT1517 | Jable 1, Fuerteventura | 28°38′38″N, 13°58′28″W | Aeolian deposits | PIRIR290, IRSLF | – |
BT1519 | Fuerteventura, Spain | 28°39′09″N, 13°57′27″W | Aeolian deposits | PIRIR290, IRSLF | – |
BT1525 | Jable 2, Fuerteventura | 28°38′50″N, 13°58′38″W | Aeolian deposits | PIRIR290, IRSLF | |
BT1528 | Jable 2, Fuerteventura | 28°38′50″N, 13°58′38″W | Aeolian deposits | PIRIR290, IRSLF | – |
BT1529 | Montana Roja, Fuerteventura | 28°38′59″N, 13°51′08″W | Aeolian deposits | IRSLF | – |
BT1401 | Eifel, Germany | 50°04′39″N, 07°01′43″E | Quartzitic slate | PIRIR290 | |
BT1415 | Vârghis, Romania | 46°12′58″N, 25°32′36″E | Aeolian cave deposit | PIRIR290 | |
BT1416 | Vârghis, Romania | 46°12′58″N, 25°32′36″E | Aeolian cave deposit | PIRIR290 | |
BT1417 | întorsura Buzăului, Romania | 45°43′02″N, 26°04′13″E | Loamy hillslope deposit | PIRIR290 | – |
C-L3704 | Urluia, Romania | 44°05′42″N, 27°54′07″E | Loess | PIRIR290 | – |
C-L3707 | Urluia, Romania | 44°05′42″N, 27°54′07″E | Loess | PIRIR290 | |
C-L3778 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Loess | PIRIR290 | |
C-L3780 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Loess | PIRIR290 | |
C-L3784 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Loess | PIRIR290 | |
C-L3786 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Loess | PIRIR290 | |
C-L3787 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Pedogenetically overprinted loess | PIRIR290 | |
C-L3788 | Stalać, Serbia | 43°40′39″N, 21°25′04″E | Loess | PIRIR290 | |
C-L4029 | Vrsac, Serbia | 45°09′10″N, 21°09′30″E | Lacustrine sediment | PIRIR290 | |
C-L4030 | Vrsac, Serbia | 45°09′10″N, 21°09′30″E | Lacustrine sediment | PIRIR290 | |
C-L4031 | Vrsac, Serbia | 45°09′10″N, 21°09′30″E | Lacustrine sediment | PIRIR290 | |
C-L3789 | Ságvár, Hungary | 46°49′18″N, 18°05′23″E | Loess | PIRIR290 | |
C-L3791 | Ságvár, Hungary | 46°49′18″N, 18°05′23″E | Loess | PIRIR290 | |
C-L3792 | Ságvár, Hungary | 46°49′18″N, 18°05′23″E | Loess | PIRIR290 | |
C-L3793 | Ságvár, Hungary | 46°49′18″N, 18°05′23″E | Loess | PIRIR290 | |
C-L3795 | Bodrogkeresztúr, Hungary | 48°08′50″N, 21°21′48″E | Loess | PIRIR290 | |
C-L3797 | Bodrogkeresztúr, Hungary | 48°08′50″N, 21°21′48″E | Pedogenetically overprinted loess | PIRIR290 | |
C-L3799 | Bodrogkeresztúr, Hungary | 48°08′50″N, 21°21′48″E | Loess | PIRIR290 |
Measurement protocols employed for a-value determination. Step 1 in the first SAR cycle is carried out using α-irradiation, while all subsequent irradiations refer to β-doses. The pIRIR290 protocol follows Thiel et al. (2011), while the IRSLF protocol was adopted from Faust et al. (2015). Stimulation times for IRSL50 and pIRIR290 signals were 300 s (Bayreuth) or 200 s (Cologne); an IRSL readout at 325°C for 600 s (Bayreuth) or 200 s (Cologne) intended to fully zero IRSL traps prior to the next regeneration cycle.
pIRIR290 | IRSLF | ||||
---|---|---|---|---|---|
Step | Procedure | Signal | Step | Procedure | Signal |
0 | Resetting of the natural signal | 0 | Resetting of the natural signal | ||
1 | Irradiation with dose | 1 | Irradiation with dose | ||
2 | Preheat (320°C, 60 s) | 2 | Preheat (270°C, 120 s) | ||
3 | IR stimulation (50°C, 300 s or 200 s) | 3 | Pause (1200 s) | ||
4 | IR stimulation (290°C, 300 s or 200 s) | 4 | IR stimulation (125°C, 300 s) | ||
5 | Irradiation with test dose | 5 | Irradiation with test dose | ||
6 | Preheat (320°C, 60 s) | 6 | Preheat (270°C, 120 s) | ||
7 | IR stimulation (50°C, 300 s or 200 s) | 7 | Pause (1200 s) | ||
8 | IR stimulation (290°C, 300 s or 200 s) | 8 | IR stimulation (125°C, 300 s) | ||
9 | IR stimulation (325°C, 600 s or 200 s) | 9 | Return to step 1 | ||
10 | Return to step 1 |
Relative change of the Lα/Tβ ratio after repeated Lα – Tβ cycles (see main text for further information).
Sample | BT1258 | BT1259 | ||
---|---|---|---|---|
Protocol | IRSLF | PIRIR290 | IRSLF | plRIR290 |
3 cycles | 6% | 3% | 9% | 8% |
7 cycles | 5% | 7% | 12% | 13% |
Results of a-value determination. In contrast to Table 1, samples are grouped according to the measurement protocol used for a-value determination. n is the number of measured aliquots per sample. The a-value is derived as the arithmetic mean of individual aliquots of one sample; the averaged measurement uncertainty Δa is calculated using the formula Δa = [(Δa12+Δa22+…+Δan2)/n]0.5 SD is the standard deviation. The low-temperature IRSL readout of sample C-L3789 was carried out both at 50°C and 80°C, as indicated in the first column. Systematic errors relating to α- and β-source calibration are not considered in this compilation.
Sample code | Protocol | Resetting | α-dose (Gy) | Δ | SD (1 | ||
---|---|---|---|---|---|---|---|
BT1257 | pIRIR290 | Hot bleach | 298 | 4 | 0.078 | 0.005 | 0.005 |
BT1258 | pIRIR290 | Hot bleach | 298 | 4 | 0.087 | 0.005 | 0.008 |
BT1259 | pIRIR290 | Hot bleach | 298 | 4 | 0.083 | 0.004 | 0.007 |
BT1344 | pIRIR290 | Hot bleach | 298 | 4 | 0.084 | 0.006 | 0.009 |
BT1344 | pIRIR290 MAAD | Hot bleach | – | – | 0.035 | 0.004 | – |
BT1345 | pIRIR290 | Hot bleach | 633 | 4 | 0.102 | 0.009 | 0.011 |
BT1345 | pIRIR290 MAAD | Hot bleach | – | – | 0.075 | 0.008 | – |
BT1513 | pIRIR290 | Hot bleach | 298 | 3 | 0.089 | 0.005 | 0.006 |
BT1515 | pIRIR290 | Hot bleach | 298 | 3 | 0.077 | 0.009 | 0.010 |
BT1517 | pIRIR290 | Hot bleach | 298 | 3 | 0.076 | 0.003 | 0.003 |
BT1519 | pIRIR290 | Hot bleach | 298 | 3 | 0.071 | 0.005 | 0.003 |
BT1525 | pIRIR290 | Hot bleach | 298 | 3 | 0.094 | 0.008 | 0.011 |
BT1526 | pIRIR290 | Hot bleach | 298 | 3 | 0.107 | 0.008 | 0.004 |
BT1527 | pIRIR290 | Hot bleach | 298 | 3 | 0.090 | 0.010 | 0.006 |
BT1528 | pIRIR290 | Hot bleach | 298 | 3 | 0.075 | 0.004 | 0.007 |
BT1401 | pIRIR290 | Hot bleach | 373 | 2 | 0.091 | 0.008 | 0.008 |
BT1415 | pIRIR290 | Hot bleach | 298 | 4 | 0.085 | 0.004 | 0.006 |
BT1416 | pIRIR290 | Hot bleach | 298 | 4 | 0.083 | 0.003 | 0.003 |
BT1417 | pIRIR290 | Hot bleach | 298 | 4 | 0.091 | 0.004 | 0.007 |
C-L3704 | pIRIR290 | Annealing | 79 | 2 | 0.109 | 0.006 | 0.009 |
C-L3707 | pIRIR290 | Annealing | 79 | 2 | 0.115 | 0.006 | 0.008 |
C-L3778 | pIRIR290 | Annealing | 79 | 3 | 0.116 | 0.006 | 0.010 |
C-L3780 | pIRIR290 | Annealing | 79 | 2 | 0.108 | 0.007 | 0.015 |
C-L3784 | pIRIR290 | Annealing | 79 | 3 | 0.119 | 0.010 | 0.016 |
C-L3786 | pIRIR290 | Annealing | 79 | 2 | 0.085 | 0.006 | 0.009 |
C-L3787 | pIRIR290 | Hot bleach | 197 | 1 | 0.078 | 0.007 | – |
C-L3787 | pIRIR290 | Annealing | 394 | 6 | 0.084 | 0.003 | 0.016 |
C-L3788 | pIRIR290 | Annealing | 394 | 6 | 0.105 | 0.004 | 0.010 |
C-L3789 (50C) | pIRIR290 | Annealing | 79 | 3 | 0.103 | 0.007 | 0.012 |
C-L3789 (80C) | pIRIR290 | Hot bleach | 197 | 3 | 0.109 | 0.006 | 0.017 |
C-L3789 (80C) | pIRIR290 | Annealing | 296 | 11 | 0.074 | 0.003 | 0.009 |
C-L3791 | pIRIR290 | Annealing | 394 | 6 | 0.084 | 0.003 | 0.016 |
C-L3792 | pIRIR290 | Annealing | 394 | 5 | 0.091 | 0.004 | 0.016 |
C-L3793 | pIRIR290 | Hot bleach | 197 | 2 | 0.100 | 0.004 | 0.005 |
C-L3793 | pIRIR290 | Annealing | 394 | 6 | 0.089 | 0.003 | 0.020 |
C-L3795 | pIRIR290 | Annealing | 394 | 5 | 0.107 | 0.004 | 0.005 |
C-L3797 | pIRIR290 | Annealing | 394 | 6 | 0.100 | 0.004 | 0.005 |
C-L3799 | pIRIR290 | Annealing | 394 | 3 | 0.096 | 0.004 | 0.007 |
C-L4029 | pIRIR290 | Hot bleach | 50 | 5 | 0.113 | 0.009 | 0.010 |
C-L4030 | pIRIR290 | Hot bleach | 50 | 5 | 0.120 | 0.012 | 0.010 |
C-L4031 | pIRIR290 | Hot bleach | 50 | 5 | 0.115 | 0.010 | 0.019 |
BT1337 | IRSLF | Hot bleach | 199 | 4 | 0.077 | 0.014 | 0.005 |
IRSLF | Hot bleach | 199 | 4 | 0.074 | 0.003 | 0.003 | |
BT1340 | IRSLF | Hot bleach | 199 | 4 | 0.096 | 0.009 | 0.002 |
BT1341 | IRSLF | Hot bleach | 199 | 4 | 0.099 | 0.014 | 0.007 |
BT1342 | IRSLF | Hot bleach | 199 | 4 | 0.086 | 0.010 | 0.008 |
BT1343 | IRSLF | Hot bleach | 199 | 4 | 0.078 | 0.003 | 0.003 |
BT1344 | IRSLF | Hot bleach | 199 | 4 | 0.091 | 0.006 | 0.005 |
BT1344 | IRSLF MAAD | Hot bleach | – | – | 0.079 | 0.006 | – |
BT1345 | IRSLF | Hot bleach | 199 | 4 | 0.085 | 0.007 | 0.003 |
BT1345 | IRSLF MAAD | Hot bleach | – | – | 0.069 | 0.004 | – |