Luminescence (version 0.4.1)

analyse_SAR.CWOSL: Analyse SAR CW-OSL measurements

Description

The function performs a SAR CW-OSL analysis on an RLum.Analysis object including growth curve fitting.

Usage

analyse_SAR.CWOSL(object, signal.integral.min, signal.integral.max, 
    background.integral.min, background.integral.max, rejection.criteria, 
    dose.points, mtext.outer, plot = TRUE, plot.single = FALSE, 
    ...)

Arguments

object

RLum.Analysis(required): input object containing data for analysis

signal.integral.min

integer (required): lower bound of the signal integral

signal.integral.max

integer (required): upper bound of the signal integral

background.integral.min

integer (required): lower bound of the background integral

background.integral.max

integer (required): upper bound of the background integral

rejection.criteria

list (with default): provide list and set rejection criteria in percentage for further calculation. Allowed arguments are recycling.ratio, recuperation.rate, palaeodose.erro

dose.points

numeric (optional): a numeric vector containg the dose points values Using this argument overwrites dose point values in the signal curves.

mtext.outer

character (optional): option to provide an outer margin mtext

plot

logical (with default): enables or disables plot output.

plot.single

logical (with default) or numeric (optional): single plot output (TRUE/FALSE) to allow for plotting the results in single plot windows. If a

...

further arguments that will be passed to the function plot_GrowthCurve

Value

• A plot (optional) and an RLum.Results object is returned containing the following elements:
• De.values
  data.frame containing De-values, De-error and further parameters
• LnLxTnTx.values
  data.frame of all calculated Lx/Tx values including signal, background counts and the dose points
• rejection.criteria
  data.frame with values that might by used as rejection criteria. NA is produced if no R0 dose point exists.
• Formula
  formula formula that have been used for the growth curve fitting
• The output should be accessed using the function get_RLum.Results.

Function version

0.5.0 (2015-01-24 23:24:06)

Details

The function performs an analysis for a standard SAR protocol measurements introduced by Murray and Wintle (2000) with CW-OSL curves. For the calculation of the Lx/Tx value the function calc_OSLLxTxRatio is used. Working with IRSL data The function was originally designed to work just for 'OSL' curves, following the principles of the SAR protocol. An IRSL measurement protocol may follow this procedure, e.g., post-IR IRSL protocol (Thomsen et al., 2008). Therefore this functions has been enhanced to work with IRSL data, however, the function is only capable of analysing curves that follow the SAR protocol structure, i.e., to analyse a post-IR IRSL protocol, curve data have to be pre-selected by the user to fit the standards of the SAR protocol, i.e., Lx,Tx,Lx,Tx and so on. Example: Imagine the measurement contains pIRIR50 and pIRIR225 IRSL curves. Only one curve type can be analysed at the same time: The pIRIR50 curves or the pIRIR225 curves. Supported rejection criteria recyling.ratio: calculated for every repeated regeneration dose point. recuperation.rate: recuperation rate calculated by comparing the Lx/Tx values of the zero regeneration point with the Ln/Tn value (the Lx/Tx ratio of the natural signal). For methodological background see Aitken and Smith (1988). palaeodose.error: set the allowed error for the De value, which per default should not exceed 10%.

References

Aitken, M.J. and Smith, B.W., 1988. Optical dating: recuperation after bleaching. Quaternary Science Reviews 7, 387-393. Duller, G., 2003. Distinguishing quartz and feldspar in single grain luminescence measurements. Radiation Measurements, 37 (2), 161-165. Murray, A.S. and Wintle, A.G., 2000. Luminescence dating of quartz using an improved single-aliquot regenerative-dose protocol. Radiation Measurements 32, 57-73. Thomsen, K.J., Murray, A.S., Jain, M., Boetter-Jensen, L., 2008. Laboratory fading rates of various luminescence signals from feldspar-rich sediment extracts. Radiation Measurements 43, 1474-1486. doi:10.1016/j.radmeas.2008.06.002

See Also

calc_OSLLxTxRatio, plot_GrowthCurve, RLum.Analysis, RLum.Results get_RLum.Results

Examples

##load data
##ExampleData.BINfileData contains two BINfileData objects 
##CWOSL.SAR.Data and TL.SAR.Data
data(ExampleData.BINfileData, envir = environment())

##transform the values from the first position in a RLum.Analysis object
object <- Risoe.BINfileData2RLum.Analysis(CWOSL.SAR.Data, pos=1)

##perform SAR analysis
results <- analyse_SAR.CWOSL(object, 
                  signal.integral.min = 1,
                  signal.integral.max = 2,
                  background.integral.min = 900,
                  background.integral.max = 1000,
                  log = "x",
                  fit.method = "EXP")

##show De results 
get_RLum.Results(results)

##show LnTnLxTx table
get_RLum.Results(results, data.object = "LnLxTnTx.table")