Re: CR-39

[Bernard Cleyet <anngeorg@PACBELL.NET>]

I see, but if most Alphas are stopped by a coupala inches of air, how
long are they in the plastic?   Ooh, OK ~ 1/2 mm for 2 Mev and 6.5 for
10.5 Mev.  Reasonable using a microscope.  Comparable for water:
respectively 0.8 and 8.9 mm.

What energy do you expect?

bc

Ludwik Kowalski wrote:

> On Tuesday, Feb 11, 2003 Bernard Cleyet wrote:
>
> > bc who's curious about LK's apparatus and saves dead
> > kinescopes for the phosphor to use as Alpha scintillator.
>
> You probably know that nuclear emulsions have been used,
> and are still used, to visualize tracks of ionizing particles.
> Then in 1960's people found tracks in some solids. Such
> tracks are visible by using an electron microscope. To make
> them visible with an optical microscope a solid must be
> etched  in an acid, such HF,  or in a base, such as NaOH.
> CR-39 is a plastic material developed to detect alpha
> particle, for example, from radon.
>
> I got samples of that material and plan to use it to measure
> alpha radioactivity in water. Unfortunately the tracks due to
> alpha particles that I saw today (?) were not not very
> different from the background found in a blank CR-39.
> > Ludwik Kowalski wrote:
> >
> > > I would appreciate if somebody with experience in
> > > using CR-39 (or lexan), to detect alpha particles,
> > > could contact me in private. I tried to use these
> > > detectors today but was not successful.