LLD for Albedo Dosimeter

[Bob Flood <bflood@SLAC.Stanford.EDU>]

I think I have an interesting puzzle for some of you math fans out there. I
think I could figure this one out myself, but I find there just aren't
enough hours in the day any more...

So, I'm hoping someone out there can point me to a convenient reference as
a shortcut.

We use albedo TLDs (2 types, a loose disk LiF system and the Panasonic
UD-802) in several different geometries to monitor area and personnel
neutron dose. We have various moderating materials to use, and I'd like to
determine the LLD for each dosimeter/moderator combination.

The methods I have always used for LLD calculations use the background DOSE
and the associated standard deviation as well as bias and standard
deviation data for small, non-background dose measurements. We have
developed dose conversion factors for a variety of neutron spectra, and I
would like to determine the LLD for each. The traditional (NVLAP, DOELAP)
calculation method doesn't really allow for what I want to do.

For each dosimeter system, we can determine the average background SIGNAL
for each element and the associated standard deviations. What I would like
to calculate is the minimum detectable signal above background for each
such element. These values could then be used with the dose conversion
factors to determine the minimum dose that could be detected at each
energy. I base this on the assumption that the minimum detectable signal
attributable to neutron dose above natural background is a characteristic
of the ambient background and the measurement conditions and devices, and
once determined, this minimum detectable signal above noise can be used to
calculate the neutron dose necessary to generate that signal at each
neutron energy.

Does anyone know of a good reference or two that I could look at for
calculational techniques?

---------
Bob Flood
Dosimetry Group Leader
Stanford Linear Accelerator Center
(650) 926-3793
bflood@slac.stanford.edu