NukeWorker Forum

Career Path => Radiation Safety => Topic started by: bigjoemonger on Jan 14, 2018, 10:20

Title: Alpha beta crosstalk
Post by: bigjoemonger on Jan 14, 2018, 10:20
I have[/size] a Ludlum 3030P alpha beta counter. This [/color][/size]has windows set from 70 - 700 mV and 1000 - 4000 mV but i only use it to measure Alpha smears. This instrument comes optional with detector[/color][/size] shielding which reduces background betas. Since I'm not measuring betas does it matter that I don't have the shielding?[/color][/size]I know that there is some beta to alpha crosstalk but would allowing this backgroundbeta in significantly impact my alpha counts?[/color]
Title: Re: Alpha beta crosstalk
Post by: GLW on Jan 14, 2018, 11:14
which detector?


43-10-1 or something else?
Title: Re: Alpha beta crosstalk
Post by: bsdnuke on Jan 14, 2018, 12:30
That should be correct. This is the current one formerly called a 2929
Title: Re: Alpha beta crosstalk
Post by: Rennhack on Jan 14, 2018, 11:53
I have a Ludlum 3030P alpha beta counter.
which detector? 43-10-1 or something else?
That should be correct. This is the current one formerly called a 2929

The 3030P has a solid state detector build in.

Alpha to Beta Crosstalk  < 5%
Beta to Alpha Crosstalk  < 0.1%
http://ludlums.com/products/all-products/product/model-3030p (http://ludlums.com/products/all-products/product/model-3030p)

There is <0.1% beta to alpha cross talk.  Less beta's WILL mean less cross talk.  But at <0.1%, do you care?  Personally, I would add the shielding if it doesn't cost much.  Because I'm American, and more (precision) is better. If it costs anything significant, I don't think I could justify a fraction of 0.1% improvement. How many sigma's are we looking for, anyways?


A 2929 is a Scaler (meter).  A 43-10-1 is a detector.  A 43-10-1 detects the radiation, and sends a pulse to the 2929 that measures the pulse.  A 2929 doesn't HAVE to be paired with a 43-10-1, but almost always is. (Not directed at you GLW)
http://ludlums.com/products/all-products/product/model-2929-with-43-10-1 (http://ludlums.com/products/all-products/product/model-2929-with-43-10-1)

The 3030E replaced the 2929, with an external 43-10-1.
http://ludlums.com/products/all-products/product/model-3030e-with-43-10-1

It has:
Alpha to beta cross talk: 10% or less
Beta to alpha cross talk: 1% or less

A 3030 (no E no P, just "3030") has the detector built into the meter, like the 3030P:
http://ludlums.com/products/all-products/product/model-3030 (http://ludlums.com/products/all-products/product/model-3030)
The Model 3030 Scaler incorporates an internally housed ZnS(Ag) plastic scintillator detector (like the 43-10-1, but internal) with shielded stainless steel sample tray.

It also has:
Alpha to beta cross talk: 10% or less
Beta to alpha cross talk: 1% or less
Title: Re: Alpha beta crosstalk
Post by: GLW on Jan 15, 2018, 06:15

 (Not directed at you GLW)


It's okay, I focused on "optional shielding" and not on 3030"P",...

details count,...
Title: Re: Alpha beta crosstalk
Post by: SloGlo on Jan 15, 2018, 05:38
wail, the shielding package is two be used too reduce beta bkg. that sayed, it's probly most relevant to the level of alpha contamination bean measured, bee caws a 20% reduction in beta bkg mite have a grater data impact on negligible alpha contamination than the same bkg reduction when measuring thousands of alpha dpm.
Title: Re: Alpha beta crosstalk
Post by: atomicarcheologist on Jan 17, 2018, 02:09
wail, the shielding package is two be used too reduce beta bkg. that sayed, it's probly most relevant to the level of alpha contamination bean measured, bee caws a 20% reduction in beta bkg mite have a grater data impact on negligible alpha contamination than the same bkg reduction when measuring thousands of alpha dpm.
Agreed, as proving the negative is, at times, challenging.