Search found 454 matches

by Wilfried Heil
Fri Oct 09, 2009 10:19 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Power Supply Success with Fusion Results
Replies: 24
Views: 6606

Re: Power Supply Success with Fusion Results

<t>Tyler - your calculations are mostly correct, except for the division by the head area. That is included in the detector sensitivity already. So your neutron emissions should be about 18500/s from the fusor, which looks like a reasonable number.<br/> <br/> This assumes a sensitivity of 55 cpm/mre...
by Wilfried Heil
Tue Sep 01, 2009 11:00 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Need Help Identifying
Replies: 4
Views: 2633

Re: Need Help Identifying

<r>This is the detector head of a medical gamma camera with 19 PMTs. <br/> <br/> With its associated electronics, it can detect the position of the scintillations from gamma rays and add them up to build an image with a resolution of about 32x32 pixels. It's something I would like to keep intact, bu...
by Wilfried Heil
Fri Aug 28, 2009 7:59 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Conflat gasket suppliers in UK?
Replies: 16
Views: 6395

Re: Conflat gasket suppliers in UK?

http://www.caburn.co.uk/

The silver plating prevents the copper from oxidizing during bakeout.
It is probably not required in your case.

You should use annealed copper gaskets for the viewport though.
by Wilfried Heil
Sun Aug 16, 2009 12:21 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Question?
Replies: 28
Views: 6760

Re: Question?

The gel contains mostly water, with the superheated Freon droplets within. Freezing is likely to destroy the gel matrix, so that the bubbles will become unstable and pop.

Since you've got two of them, why don't you freeze one and let us know?
by Wilfried Heil
Sun Aug 09, 2009 9:43 pm
Forum: Images du Jour
Topic: Archived - on the way to a microtron, first light from the magnetron
Replies: 12
Views: 7467

Re: Archived - on the way to a microtron, first light from the magnetron

Another interesting device. Good to see that the vacuum tube technology still has its uses, especially for HV. I like the neon hodoscope. Hope you can dig up a suitable magnet and chamber for the microtron.

What electron energies do you expect to reach?
by Wilfried Heil
Wed Aug 05, 2009 8:07 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Lithium Fluoride detectors?
Replies: 7
Views: 4833

Re: Lithium Fluoride detectors?

<t>Probably not sensitive enough and not a real time detector. The total emitted neutron doses here are very small, fortunately. What would work is a (Li-6)F:Eu scintillator with a moderating sphere. I've seen some appear used occasionally, but they are quite expensive, about twice the cost of a 20"...
by Wilfried Heil
Wed Jul 29, 2009 12:23 am
Forum: Images du Jour
Topic: Archived - First star mode
Replies: 17
Views: 6694

Re: First star mode

<t>Those are pretty examples of a "bugle jet" glow discharge. You will recognize star mode (i.e. a hollow cathode discharge) immediately when you see it.<br/> <br/> There is something like a phase transition between the two modes of discharge. At a still somewhat lower gas pressure than what you hav...
by Wilfried Heil
Wed Jul 15, 2009 5:21 pm
Forum: Images du Jour
Topic: Archived - Electronbeam in air
Replies: 10
Views: 11729

Re: Electronbeam in air

<r>Nice work and as usual, great improvisation! I'm also curious how much current you are emitting into the beam.<br/> <br/> Below is an article on an e-gun (Navy funded) by J.Ziegler, one of the makers of SRIM.<br/> ><URL url="http://www.srim.org/e-Zapper/2005%20e-Zapper%20Project/OEZiegle.doc"><LI...
by Wilfried Heil
Sun Jun 21, 2009 7:52 pm
Forum: Images du Jour
Topic: Archived - Spark Chamber
Replies: 8
Views: 5476

Re: Spark Chamber

Nice experiment! Would it be possible to seal the chamber, if it is filled with neon at atmospheric pressure or maybe a helium/neon mixture?
by Wilfried Heil
Sun Jun 21, 2009 7:48 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Original Farnsworth Fusor
Replies: 7
Views: 2985

Re: Original Farnsworth Fusor

<t>Good question. The first reason probably is that it would be much more challenging to build an electron gunned fusor with a "virtual cathode" than the Hirsch-Meeks fusor with a central grid.<br/> <br/> The other obstacle is that no detectable amount of fusion appears to have ever been seen from t...