Anomalous event

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Jon Rosenstiel
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Anomalous event

Post by Jon Rosenstiel »

This afternoon an anomalous event occured just as I was settling in on an 18-minute indium activation run.

I was 30 to 45 seconds into the first run of the day and had just leveled the power off at 43kV, 17mA. At this power level my Ludlum 12-4 rem ball neutron detector normally indicates around 52 mrem, (2.0E+06 neutrons/second), just above one-half scale on the x10 range.

As I was saying, I had just leveled off, (stabilized), the power when the “chirping” of the neutron counter caught my attention. I quickly glanced at the kV meter and the mA meter and the readings were normal. I then turned my attention to the ratemeter and saw that the needle was pegged at over 100 mrem and the speaker was “chirping” wildly! This surprised the crap out of me and I immediately shut down the fusor. (My newly added cooling fan makes a bit of noise, so I was concerned that something may have been going wrong that I was unable to hear.)

At the time of the “event” all of my settings were settings that I had used many times before. The chamber temperature was climbing through 35C. The pressure was stabilizing at around 13.5 mTorr. The D2 flow was normal.

After shutdown it took several seconds before the ratemeter needle finally moved off of the pegged position and slowly dropped down scale. (Because of the charge on the meter capacitor. When the power was cut the neutrons immediately stopped as the ratemeter's speaker quit "chirping"). I hit the zero button and resumed my activation experiment with no further problems. I noticed that for the remainder of the activation run my fusor’s output seemed exceptionally strong, hitting 60 mrem on several occasions.

Unfortunately, I hadn’t heeded Richard Hull’s advice and wasn’t prepared for this event. (See Richard’s “Fostini Burst Event” post of 2002-12-02 in this forum). The dumb thing is, I had just started an indium activation experiment, but didn’t have the smarts to remove the indium from the H2O and immediately check it for activation! Duh! It seems as though I was more interested in finishing my activation experiment than trying to determine what had happened! (Isn’t hindsight always 20-20?)

Was this event real? I do know my neutron counter was pegged and “chirping” like crazy. But was this from some super neutron event, or could it have been electromagnetic interference finding it’s way into my detector? Usually EMI comes from arcing, and if there is arcing the mA meter always jumps around. But at the time of the “event” the meter needle was dead stable.

I guess at this point all I can do is to be better prepared and thinking more clearly if this happens again. All in all, an exciting day!

Jon Rosenstiel
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Re: Anomalous event

Post by 3l »

I would have removed the change from my pockets and check ed for activation.
This method of focusing with a grid has great potential.
I get activation from pulse as a matter of routine now.
If I ever got what Dr Miley claimed sitting behind a moderator is very bad. Jon you are getting to the serious zone. I would avoid the moderated areas and maybe a little distance wouldn't hurt.
Great news though.

Keep on Fusing!
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Richard Hull
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Re: Anomalous event

Post by Richard Hull »

Amazing! Thank you Jon for the thoroughly detailed event report! It was easy to read and answered virtually every question that I had before I had to ask. You have already done the obligatory mea culpa so I will not scold. That indium was truly the rosetta stone. It was inplace ready to NOT LIE. Too bad.

I have not reported extensively on this, but the Farnsworth team has multiple tales of just this sort of event!!! Is this a form of pre-ignition? Are we back at the cusp of real fusion? Crap like this re-ignites the spark of maybe seeing fusion in my lifetime.

In future, hit the power switch..... Forget all else.... Yank the indium and start the geiger counter. If you find 30 minutes run time of activation in a 3-5 second burst event, you are King Doody! You also might lay off fusion for aweek or two to let your immune system do its appointed job.

Right now, as it stands, this could have been a moisture feedback induced runaway of the front end of the neut counter. Ocam's razor would favor this rather than some sort of pre-ignition. The fact that your counter instantly fell silent with HV power removal militates against a runaway front end. The indium would have been the ultimate arbiter here. (no electronic lies told)

I am virtually convinced now that this stuff is real and directly related to the SPHERICAL and COLLIDER nature of the device.

I also believe that if you want neutrons the best way is to grab two potent ion guns and have their deuteron beams collide head on. However, this ain't gonna do any usable power fusion or bump into ignition.

I have rolled a lot of half baked thoughts around in my age dulled noodle as to why these anomolous runaway events occur. Among the most interesting is some sort of resonant rise of a runaway standing wave in the microwave region re-enforcing the action of the fusor and self feeding of the avaialble input energy. Not too whacko, but a stretch to be sure.

We are not getting any real efficiency off the power we feed in to any simple fusor so if the fusor converts .0000001% of the input power in neutrons and runs away to a one hundred fold increase we are still at .00001% power ultilization or conversion. Therefore, we are not making energy from nothing as we haven't equaled what we are feeding yet. Of course a hundred fold increase in neutrons would screw with the ole blood chemistry for a few days. I dare not think of break even even with a 700 watt fusor for that means fully 350 watts of neutrons and 350 watts of protons sailing about. (read death sentence.)

To wrap it up, a full computer controlled data logging system would have just been the cat's meow for such an event as this for being able to look back at the 6 or more levels in a time ordered sequence would have spoken volumes. But, if I had a choice between the data logger or a single timely indium reading, I would have asked for the latter.

What the hell have we here in these anomolous events?.....


Ricahrd 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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Anomalous event

Post by 3l »

Richard heres another mystery to consider.
One of the most frustrating things about pulse it is never the same!
At high amperage it is all anomolous.
When I finally get decent neutron gear I intend to do 100 shots and compare them.
Some are duds but every once in a while ,a really hot one
occurs since I have no idea when one will pop up ,I get the hell out of Dodge during all shots

Keep on Fusing!
Larry Leins
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Richard Hester
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Re: Anomalous event

Post by Richard Hester »

Actually, being behind the moderator is not nearly as bad as letting the fast neutrons zip through you. Once the neutrons are moderated down to thermal energies, the only way they can hurt you is through capture and/or activation. With the fast ones, the tissues sustain lots of damage due to proton recoil, with activation and capture following merely for dessert. If you check the RBE of fast neutrons, you will find that they are much worse than thermals.
The best of all worlds for shielding would be a moderator backed with cadmium or boron, then lead. The cadmium or boron soak up the moderated neutrons, while the lead screens out the capture radiation from both the neutron stopper and the moderator.
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Re: Anomalous event

Post by Paul_Schatzkin »

Yikes.

First, I am VERY suprised to read of such an event in one of these "simple" Hirsch/Meeks Variations of the Farnsworth Fusor. We have been led to believe that this version is not capable of the kinds of energy levels of the more sophisticated, ion-gunned versions, but what you describe sounds very much like the kind of "runaway" event encountered in the Pontiac Street labs.

2nd, that leads me (and I am NOT the most well-informed observer here) to believe that the real power in these devices is not the configuration of the grid-v-guns, but in the poissor itself. That, it seems to me, is the real invention here. Farnsworth himself said that the poissor was capable of far more than the fusing of light nuclei lets on...

3rd, for whatever its worth, remember this: we keep forgetting the protons. For every neutron that your counter chirps, there is also a proton, and those protons are working against the anode. What is the possibility that something was causing that output to recirculate into the system?

4th...Richard, you may have to create a sub-group of our "neutron club" - the Runaways!

5th... get yerself some shielding.

I may have more to add as it occurs to me... I just wanted to let you know I'd read this and am quite favorably impressed with the news...

--PS
Paul Schatzkin, aka "The Perfesser" – Founder and Host of Fusor.net
Author of The Boy Who Invented Television: 2023 Edition – https://amz.run/6ag1
"Fusion is not 20 years in the future; it is 60 years in the past and we missed it."
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Re: Anomalous event

Post by 3l »

Hi Richard:

Any neutron exposure is not good.
Jon like most experimenters are using a thin moderating tank less than 5ft which is the minimum for a thick moderator.
I would agree with you about the exposure if it were a thick tank but all activation so far is with a thin one increasing the chance of activation in the operators body. A human is nearly all water
but a high energy neutron will moderate in your body and pass out the other side in most cases. (skinny guys only...we tubby's got to leave now) It takes a really high flux of high speed neutrons to get dangerous (the rbe is figured at a rate of a nuclear reactor 10^11 n/sec...slow neutrons are pretty damaging if enough go into a human.). But a flux of high speed neutrons moderated by a thin water tank will virtually guarantee that any human standing behind it will get the max neutron dose.

Keep on Fusing!
Larry Leins
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Re: Anomalous event

Post by 3l »

Hi Professor:
You ain't seen nothing yet!
The so called simple Hirsh/Meeks setup has a lot more potential
than we have explored as yet.
I am thrilled and amazed daily by pulsing the "simple grid".
All pulses generate large activation in my silver coin detectors.
Soon I will be able to push it beyond the Dr Miley record for pulsed devices...I'm really close to his mark now.
My goal is to push into the regeam that is detailed in 1 hp fusor.
My all conflat stuff for a steady fusor is getting in gear.
Im now converting my pulse demo machine into a multicusp demo.
My hope is to demonstate a high power continous fusor in a glass bell jar... thats right neutrons under glass!

So in conclusion I would like to state that the simple grid is not dead. We have barely scratched the surface.

Keep on Fusing!
Larry Leins
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Re: Anomalous event

Post by Richard Hester »

The RBE for fast neutrons is five times that for thermals, for a reason. If a few inches of paraffin will moderate a neutron, so will a human body, even one as skinny as mine.The process of moderation in the body is the killer, as it generates energetic protons, which have almost as high an RBE as alpha particles (very high), and are in the right place to do the maximum amount of damage. I 'm not saying that one should blithely expose ones self to a beam of thermal neutrons, but the fast neutrons are really the ones to look out for.
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Richard Hull
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Re: Anomalous event

Post by Richard Hull »

Pulsed fusors will not be very repeatable in amateur hands. Large power deliveries in microsecond time frames will be all over the place due to about a thousand instantaneous variables which some intrumentation is not even fast enough to report. (micro pressure bursts, unexpected instantaneous current paths through the gas or even insulated structure dielectric anomolies, and the list goes on. In pulses you have a lot of intantaneous power to burn....(read burn off in wasted current paths or in ultra ideal paths or any admixture of both situations.)

This is one reason why cold fusion and pulsed cold fusion systems are laughed at. Nothing is repeatable on command and a lot of the folks involved in data collection (pros and amateurs) are often not the ideal metrologists needed to give a cache of credibility to some of the claims.

The trouble with most pulsed hot fusion systems is that the only way to extract the energy, weak or mighty is by absorbing the neuts and heating water. "Put on the kettle" so to speak....a giant leap back to an over mature steam technology inelegance and well understood and often significant loses. How long must we continue to boil water for electricity?

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Anomalous event

Post by 3l »

Hi Richard:

I'm just happy to get it to work half way decently.
Power delivery is not a problem.
Insulation is good for about 20,000 shots.
The big buga boo after you eliminate sharp discharge points is the grid loses .001" of it surface during the shot.
A 3/16" thick washer will last roughly a 1000 shots before replacment.
Not too bad a problem as it plates the fusor walls mostly.
I use a diverter plate to shield the electrode stalk.
No metal will withstand the backblow.
Refractories in a plasma coating might work.
I'm trying to raise the neutron count mostly.
I have acheived a minimum level that the pulse will deliver but
the runnaways welll....now!
I haven't gotten to the water stage yet.

Keep on Fusing!
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Carl Willis
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Re: Anomalous event

Post by Carl Willis »

Wow...interesting. I wish I had stuff like this happen.

Actually, I am familiar with the problems of moisture around my 12-4 and this has caused little runaways in the count. For example, while using a squirt bottle to look for vacuum leaks, a bit of water got on the outside of the cable connector one time and must have leaked in. So the counter went nuts. To appreciate how sensitive these counters are, try this: 1) disconnect the tube from the cable, so you just have the end of the cable in hand. 2) bring the end close to your mouth and exhale onto it. The counter (at least mine) goes nuts from the moisture. A piece of regular typing paper causes similar issues if touched to the center pin of the cable. Maybe it's HV leakage in the paper, maybe it's static charge on the paper, I don't know. But these are awfully sensitive counters.

Excellent and intriguing report, Jon. Keep it up!! Hope it happens again for you!

-Carl
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Re: Anomalous event

Post by guest »

Richard Hull wrote:

I have rolled a lot of half baked thoughts around in my age
dulled noodle as to why these anomolous runaway events
occur. Among the most interesting is some sort of resonant rise
of a runaway standing wave in the microwave region
re-enforcing the action of the fusor and self feeding of the
avaialble input energy. Not too whacko, but a stretch to be sure.

So it might be possible to engineer some kind of spherically
converged magnetron effect?.
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Re: Anomalous event

Post by 3l »

Hi Mark:

Knock yourself out.
That's what I'm doing!
That's what happens sometimes in a poisser.
I'm heartened that Jon has had it happen in a standard fusor.
Jon's setup would preclude run away on the counting end.
But to be absolutely sure use activation .
It does not lie at all...it's there or not there period end of statement.
I use a plain jane Gieger counter for most of my work.
I just hooked it to my nim scaler.
But for most if you get a neutron flux at all....you can listen to the count by EAR till you get what you like!
I used my hottest rock as a guidepost.
I would get 20,000 cps out of it acording to the NIST calibrated nim rig at school.
I just remembered that noise and listened to what the fusor did.
The faster the better.
When I first tried it it was an utter dud....no neutrons....air leak kills fusion dead!
So all you guys trying to make pulse fly will undoubtably go through trial hell for a few months getting the rig to go.

Keep on Fusing!
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Richard Hull
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Re: Anomalous event

Post by Richard Hull »

I am glad Carl mimed my thoughts on moisture related neutron counter runaway. Until you actually get an old Eberline and NOT clean it properly AND SEE it go nuts for apparently no reason, you will never appreciate how the front end of any BF3 system detector head is constantly vulnerable to the vagiaries of its environment.

I have said it over and over........and I'll say it again.

"Counts recorded on a BF3 neutron counter can often have nothing to do with the presence of neutrons."

The only solution is eternal vigilance and controlled cross checks via null experiments.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Anomalous event

Post by teslapark »

Wow. Congrats on the interesting event, Jon! I think everyone else had already said what I might say about it, except I do plan to run more than one neutron counter at a time. I have enough materials on hand to make 3 scintillation detectors (2 BC-720's and 1 BC-400). This seems advisable, because (considering the time between Fostini's and Rosenstiel's) these events are just rare enough that you hate to be caught unaware, but just common enough to be worth preparing for. Having some moderated indium around at all times (or some other quick decay isotope) would also be a great idea.

BTW- I am back home now for the summer. As I type this I have a half-finished "hotel cart" in the garage for the fusor. I should have enough vacuum stuff now to make a fusion ready system. Should be posting pictures of the progress soon.

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Re: Anomalous event

Post by Starfire »

Jon, it will be worth while to follow Richard Hull's advice and stay in the cooler for a few weeks, then repeat the initial conditions but include the data logger [ and shield ] A repeat would open up a whole new avenue of thought and experiment. Thank you for the report. - A great contribution.
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