Gamma Spectrometry Forum

With NaI and CsI it is impossible to have an exact linear approach , you always need a polynomial calibration and a bias that makes sense , not too high (bad linearity), not too low (low counts).
Considering what already said my the other members, I don't have other suggestions sorry.

HI, the bias voltage depends of course by the type of the detector, you should take the best value, inside the allowed bias values of the photomultiplier, that gives you the best linear attitude and the best sensibility. The two scintillators have been set at 650V for the Scionix and 800V for the GS...

Hi Forum, It all started with the search for and measurement of Cs-137 in 90 g of ash obtained from firewood. In some areas of north-eastern Italy, it is still possible to detect the presence of Cs-137 originating from the Chernobyl accident. This is a very low activity, measured with my HPGe at abo...

thanks Steven,
i have ordered the 10uCi which is the minimum activity. I think this will be more than sufficient to make the calibration and test the xrays probe.

Hi all, I am going to import a Fe55 (5.9kev) source from Spectrum Techniques to test and calibrate my x-rays probe. I can buy 10uCi and 25uCi mostly at same price, just 50 usd difference. Is there a unknown to me reason why I should avoid a source with more power considering also that 1/2T is 3,7 ye...

AH!! :-) so it makes a LOT of sense. I thought it was a simple interpolation and in that case more points you have better is. a second order polynomial is anyway the minimum: it is very difficult if not impossible to have a precise calibration on all the spectrum with a second order. maybe introduci...

Hi Steven,
I am really looking forward to test it during my vacation time :-)
if you plan to add more points for energy calibration (example 5-10 as in PRA) it will become almost perfect ;-) (if not already)
thanks
Marco

Hi Steven,
I use PRA on W11 PRO since 1 year without any problem.

Thanks Steven,
yes temp. probe is a GREAT feature especially for long-time spectrum
understood for Pra. I also use BQ and Impulse so it could be okay
i will think about it.
thx

Hi Steven, very interesting and glad that I did not replace my GS-USB-PRO with V5 so now I can consider the 8000 :-) few questions for you: 1) did you notice any improvment in the fwhm using the digital ? 2) the pulse shape control has a present for NaI. is it possible to have the preset for CsI, fo...