On the longer PT time issue, I agree, but when I tried to go to 32, it was not offered, only up to 25.6. Maybe there's another setting that when selected limits the PT range? I'm sure I saw 32 and maybe longer? offered before.......
Sorry the cap stays on for protection, it is one of my modified caps with a Kapton window.
Geo
----- Original Message -----
From: Dude <dfemer@...>
To:
[email protected]Sent: Fri, 30 Oct 2020 22:35:10 -0400 (EDT)
Subject: Re: [XRF] 59.5keV spectrum cleanup
Try
a longer PT and threshold setting see if the noise gets better. Also take off the
plastic cap
I
don¡¯t see any Ar yet.
Dud
?
25.6 like last run, but auto threshold adjust applied. 8500s update .mca
below. Didn't help?
"noise" at low end, did noticeably improve definition of peaks
above 3 keV.
3.3 yes it is Ka1 of Potassium. But let's think about element K. for a moment,
a portion of it is K-40 and that has something like 10% decay path to Ar gas.
K-40 is loaded with 3.19 2.98 and 3.19 keVs. Then add the stable Ar in the air
which is really easily ionized, you might be getting a huge dose of Ar XRF
because of? the radioactive source.
Also the "noise" at the low end- I'm wondering if it has more to do
with the X-Ray photon's photopeak being scattered? by O2, and other air
molecules.?
Geo
? K at 3.3. noise at 4.5?? Cr at 5.42 and U Ll at 11.64
