First attempt at activating Indium

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Mark Rowley
Posts: 472
Joined: Sun Dec 29, 2002 5:20 am
Real name: Mark Rowley
Location: Sacramento California

First attempt at activating Indium

Post by Mark Rowley » Wed Jan 01, 2020 9:32 pm

The past few days I’ve been working on indium activation with my Fusor. To do so, I assembled the following:

6x6” paraffin moderator cut in half
1.5x1.5” sq indium foil
LND7311 pancake at 900v
Nucleus 500 digital scaler

The indium foil was placed between the two 3” paraffin halves and placed 8cm from the Fusor. This would place the indium approx 16cm away as it was in the center of the two paraffin halves (see pic).

-Pre activation background-
The LND7311 registered 359 normal background counts in 10 minutes which equates to 35.9cpm. I conducted the same background assessment two other times which resulted in a ~5cpm difference.

-The run-
The Fusor run consisted of:
5 minutes
40mTorr D2 pressure
3.45e5 isotropic n/s
6.91e5 fusions/s

After the run was completed and with the fusor input voltage switched off, the LND7311 pancake registered the following numbers:

Timed 1 minute counts:
1. 103cpm
2. 69cpm
3. 64cpm
4. 60cpm
5. 56cpm

It seemed to stagnate around 50-60cpm but slowly decayed to 40cpm after 1 hour.

Here’s a YT video of the first 2 minutes.

Any comments, criticisms, etc welcomed.

Mark Rowley
E54C579A-82D0-4D71-8C2D-F4CA71F24B48.jpeg (92.54 KiB) Viewed 144 times
DFFFB974-656A-4233-B90B-346125108321.jpeg (73.47 KiB) Viewed 144 times

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Richard Hull
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Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: First attempt at activating Indium

Post by Richard Hull » Thu Jan 02, 2020 12:45 am

Great work! This is classic activation and only real thermal neutrons can do this. No real-time fallible electronic detection needed. Post bombardment proof that neutrons were produced.
It is a pity that most first pass efforts at fusion rarely make enough neutrons to produce enough activation outside of questionable statistics. it takes a bit of running of a fusor and learning how to handle it to get the numbers needed to make activation a fete accompli

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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