Re: cloud chamber mystery

[LUDWIK KOWALSKI <KOWALSKIL@alpha.montclair.edu>]

Date: Wed, 04 Feb 1998 21:31:47 -0500
From: Maurice Barnhill <mvb@UDel.Edu>
Subject: Re: Cloud chamber mystery

> ...... ***What is remarkable is that the stray tracks we saw in the
> detector every five seconds or so in the absence of any source ceased 
> to show up when the Na22 was placed in the chamber.***  Why?
>
> [The source is inserted into the chamber just above the liquid alcohol
> on a pin attached to a rubber cork which then closes the insertion hole,
> so the source is in direct contact with the vapor inside the chamber.]

It hard to judge your experiment without being there. Is it possible that 
the very thin layer in which visible tracks can be formed was elimnated 
somehow when the source was introduced? (Convection, draft, cork or needle 
in a wrong place, a cover, a supporting structure, or who knows what else 
is responsible?)

If you really think that the presence of e+ is responsible for not seeing 
the "cosmic ray" tracks then wrap the needle into an Al capsule or foils 
(0.5 mm will do) and show that without changing anything else you bring 
the tracks back. Repeat this several times to confirm your hypothesis.

Maurice, you are in a perfect position to demonstrate the usefulness of
the concept of TRUTH in physics. Your assertion is either true or not; 
no fuzzy logic about this. And the rewards for being true are great ... 

Good luck, we may soon be proud of sharing the same list with you. But
I would not bet on it. Keep us informed. That is what the labs are for.

                                                Ludwik Kowalski