numOSL (version 2.0)

analyst: Equivalent dose analysis

Description

Determing an equivalent dose using data sets obtained from the single aliquot regenerative-dose (SAR) sequence.

Usage

analyst(Sigdata, Redose, sig.channel = NULL, back.channel = NULL,  mr = 0.01, typ = "cw", model = "exp", origin = FALSE,  ErrorMethod = "mc", nsim = 1000, weight = TRUE, plot = TRUE)

Arguments

Sigdata

matrix(required): a series of decay curves stored in a column-matrix

Redose

vector(required): regenerative dose values. Example, Redose=c(1,2,3,4,0,1)

sig.channel

vector(optional): channels used for signal integration, default sig.channel=1:4

back.channel

vector(optional): channels used for background subtraction, default back.channel is set equal to the last 20 channels

mr

double(with default): instrumental measurement error

typ

character(with default): type of an OSL decay curve, only CW-OSL decay curves can be analyzed currently

model

character (with default): model used for growth curve fitting, see function fitGrowth for available models

origin

logical(with default): force the fitted growth curve to pass the origin or not

ErrorMethod

character(with default): method used for assessing the standard error of an equivalent dose, see function calED for details

nsim

integer(with default): number of Monte Carlo simulations used for equivalent dose error estimation if ErrorMethod="mc"

weight

logical(with default): perform growth curve fitting using a weighted or an un-weighted procedure, see function fitGrowth for details

plot

logical(with default): plot output or not

Value

Return a list containing the following elements:

Curvedata

data used for constructing the growth curve

Ltx

standardised natural OSL signal and its standard error

LMpars

optimized parameters for the fitted growth curve

value

minimized objective for the fitted growth curve

ED

calculated equivalent dose and its standard error

RecyclingRatio

recycling ratio and its standard error

Recuperation

recuperation and its standard error (in percent)

Details

Function analyst is used for determing an equivalent dose using data sets obtained from the SAR sequence. It works in a manner similar to software Analyst written by Duller (2007). See function fitGrowth and calED for more details concerning growth curve fitting and equivalent dose calculation.

References

Galbraith R, 2002. A note on the variance of a backround-corrected OSL count. Ancient TL, 20(2): 49-51.

Duller, G., 2007. Software Analyst, user mannual. Freely available at http://www.nutech.dtu.dk/english/Products-and-Services/Dosimetry/Radiation-Measurement-Instruments/TL_OSL_reader/Software.

See Also

calED; fastED; fitGrowth

Examples

 # load package "numOSL".
 library(numOSL)
 # load data.
 data(Signaldata)
 # Early background subtraction.
 analyst(Signaldata$cw[,-1L], Redose=c(80,160,240,320,0,80)*0.13,
         sig.channel=1:2, back.channel=3:8, model="exp")