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Chapter 5
Protocols
Protocols determine how photon count data are used to establish a dose response
(growth curve). Up to now, the following protocols are implemented:
5.1
5.1.1
MASS
Growth curve
MASS is an extension of the well-known SAR protocol (single aliquot regeneration) to multi-pixel images, assuming that each pixel represents its own independent source of light and dose/age information, respectively. Thus, MASS
performs a SAR protocol on each pixel (yielding new images of spatial equivalent dose distribution, goodness of fit etc.) and on groups of pixels that have
been binned on the level of the raw signal data, i.e. regions of interest (ROIs,
e.g. for single grains)1 .
MASS use the photon count rates from multiple (n > 1) regeneration measurements
Λreg (Di , z̃j1 ,j2 )
(5.1)
where Di are the regeneration doses (with i = 1...n) and j1 and j2 the indices
of the first and the last subsequent image (channel) the raw signal was summed
over. Some Di can have the same value but not all of them. j1 and j2 have
to be the same for all Di . Thus, the simplest way to obtain the entries for the
growth curve LX is
LX (Di ) = Λreg (Di , z̃j1 ,j2 )
(5.2)
1 This means especially that the summed ROI raw signal data are converted into photon
counts and then used to establish a growth curve. This is an important difference between
AgesGalore 1 and AgesGalore 2. With the first, MASS computed equivalent doses for
each pixel first and THEN binned/averaged them to a ROI equivalent dose. This is a minute
but important difference.
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