Date: Mon, 28 Oct 2002 20:34:01 -0800

Author: "William Reitz"

Subject: Re: Visible Scintillation


I must have had a similar mis-spent youth. I remember the spinthariscope in
a Gilbert chemistry set - atomic age edition circa 1950 I inherited from my
older cousin. It included the alpha source. I spent many hours trying to see
the flashes. I convinced myself that I saw them though I doubt it.

Bill Reitz
aka Ari Bernoulli
----- Original Message -----
From: "Gary Karshner"
Sent: Monday, October 28, 2002 10:00 AM
Subject: Re: Visible Scintillation

> George,
> You bring back my misspent youth. There is a device call a
> spinthariscope that shows just the effect you are after. It consists of a
> zinc sulfide screen and typically a small radium source (alpha particle
> source). The alpha particles cause the zinc sulfide screen scintillate.
> need to look at it with dark adapted eyes.
> The instrument was invented my Sir William Crookes. It served as
> the basic detector for most of Rutherford's experiment, and probably
> motivated Geiger to invent his tube since he did much of the counting for
> Rutherford's group.
> You might look at some old issues of American Journal of Physics
> for plans. The radium source is like the one used in a cloud chamber.
> Gary
> At 09:46 AM 10/26/02 -0400, you wrote:
> >I just taught my first gamma spectroscopy lab.
> >I am now recuperating. ;-)
> >Anyway, we use an NaI detector with a photomultipler tube.
> >Can I get an NaI crystal, or some other device, that I can use
> >to show the students the scintillations? In the current lab set up,
> >they get no chance to see the photons with their own eyes.