Neutron Activation of Manganese Using Am-241 and Beryllium

Neutron Activation of Manganese Using Am-241 and Beryllium 

Here's a quick little neutron oven I piled together.

Radioisotope AM-241 gives off alpha radiation.

Beryllium hit by alpha radiation gives off neutrons.

Neutrons hit Manganese which gets irradiated and changed--also giving off gamma radiation.

Gamma radiation serves as the indicator that activation has taken place.

Our victim: good of Manganese Dioxide. It's a black power. I put some in a zip lock baggie for the test. Underneath the bottle is some hdpe plastic. Not really needed, but it's important to note that some elements need slowed down thermal neutrons to be activated. Supposedly, Manganese can be irradiated by fast (unmoderated) neutrons--thus I don't really need the hdpe plastic to slow them down, but what the heck: I've got tons of moderators: hdpe, paraffin wax, wax with boron in it, etc.

Final cap containing additional AM-241.

Various Am-241 sources piled on top of a piece of beryllium. The beryllium came from a defunct x-ray machine.

Awesome old ionizing smoke detector. It has 80 micro curies of Am-241 in it, instead of less than 1 micro curie like modern smoke detectors.

The unused portions (for my work) of the smoke detector.

Here's the cap portion of the smoke detector. So many people overlook this part, there are two little rectangular foil ribbons on the inside that are also AM-241!

Here's the big-boy AM-241 source. Yes, there are three sources in many of these big old smoke detectors!

The radioactive part is under the little cap at the top of this photo.

See that screw in the center? That's the adjustment screw that you can use to adjust how much AM-241 is exposed from the third AM-241 source when the smoke detector is in use.

Pyr-A-Larm (Pyralarm) smoke detector. This one is an F 3/5A and was just loaded with Americium 241 radioistope sources. Three in all! This is the "before" photo before I started disassembly.

These are always on eBay for $120, but sometimes they pop up for much, much less. Just be patient.


From reading the works of Carl Willis I found that radioactive manganese has a half life of about 2.5 hours, so you should let it irradiate in the neutron fluence for double that.

I'm not sure my gamma probe will be able to detect this low amount of gamma, so I may have to let the sample sit for a half-life or two in my gamma spectrometer setup.


Results to follow later and will be posted here. Busy at work and I don't have time to babysit a 5 hour gamma spectrometer run :)

Update: here's a pic of my gamma spectrometer after only two minutes. Notice the huge peak at 823mev! Success!!

See Atomic Particles With Your Own Eyes Huh, Part 3: Unleashing the fury of the alpha particle spark detector!

So You Wanna See Atomic Particles With Your Own Eyes Huh, Part 3: Unleashing the fury of the alpha particle spark detector!

When working with high voltage make sure to start by lighting a candle to St. Artemy of Verkola!    -Michael Logusz

Unleash the fury!!! My new toy: an alpha particle spark detector with an 8000 volt negatively charged ungrounded plate and extremely thin wires that are grounded. It's like a bug zapper for radioactive particles!

So far I've used: Geiger Counters, nuclear cloud chambers and a spinthariscope/radioscope to detect,  and visually see the paths various radioactive particles (alpha, beta, gamma and x-rays) leave in supercooled alcohol vapor and I've seen the flashes of light their impacts cause when smashing into a thin coating of zinc sulfide.

When an alpha particle passes in-between the wire and the plate of this alpha particle detector it ionizes the air in between: ZAP! The disk I'm holding with tweezers is 0.7 microcuries of the radioisotope Americium-241.

Every ZAP causes an avalanche: electrons start smashing there way into the electromagnetic field while ionizing the air gap between the plate and wire creating a plasma. The dielectric breakdown strength is exceeded by the electrical field's power. This rips a conductive path in the air. It's what causes lightening bolts to get all spikey, inside a sealed Geiger Counter tube is called the gas multiplication effect, but the result is the same: ZAP!

I bought this simple, but amazing device from Scientifics Direct. The first arrived with a blown out power supply. They rushed me out a replacement that works fantastically as you can tell from the videos.

In the diagram above to the upper right is an idea: layer many of these in a stack and that would give you the speed and direction of the particle!

My visceral "need to see" is met with these devices, unlike understanding through theory via mathematical formulae-which can have its own, equally powerful eureka moments. I still remember seeing Saturn for the first time at 2:22am with my telescope set up in the middle of a freezing Michigan road. Simple seeing: nowadays astronomers use telescopes that measure rather than simply look and see. In contrast, my activities are utterly primitive, but they're really fun!

This video shows a larger 0.9 microcurie source that is better insulated with protective plating: it will degrade slower, but has slightly fewer particles zinging off of it. Still plenty of fun! And all it took was 8000 volts of electricity that was negative (below the voltage of the ground point, in this case the wires).

High Voltage / Highly Weird

High voltage electricity (even without ionizing radiation) is fascinating. So are the electromagnetic fields that high voltages create. Many household devices feature transformers.

A transformer is basically two diffetent coils of wire that don't touch. The first coil gets powered by the electricity from the wall outlet plug. The electricity flowing through the coil creates an electromagnetic field. This field radiates outward and creates electricity in the nearby (but not touching) secondary coil.

Weird! But it gets weirder: if the second coil has more loops of wire it will receive/create more electricity than was pumped into the first coil from the wall outlet! That's a step up transformer. Less coils mean lower power is magically captured: a step-down transformer.

If both coils have the same amount of loops, the same amount of electricity jumps to the second coil as was pumped into the first coil. This of called an isolating transformer: all it does is isolated the wall outlet power from the device since at no time do the coils ever physically touch! Since all transformers isolated, only the ones that don't step up or down are called isolating transformers.

Here's a transformer I just got that will step up 120 volt wall outlet electricity to 7,500 volts. At the bottom left is a tiny first (primary) coil. It is not attached in any way to the rest of the transformer. The field of creates bleeds over onto the huge coil to the right: stepping up the voltage.

I was given this transformer for free yesterday, along with a bunch of other high voltage toys. I would have made an alpha spark detector with it, but since I already have one maybe this will end up as a Tesla Coil or Jacob's Ladder or who knows what.

Whatever I make will probably be a visceral seeing device, as opposed to a subtle sensing one. First I look, then I go back and visit the theory. My first love is seeing but I always (eventually) get to the theory.

Forget seeing particles, I'm working on a new string theory: I think this string might taste good! Meow.

see atomic particles with your own eyes huh? Part II

So you wanna see atomic particles with your own eyes huh? Part II

Was der Fall ist, die Tatsache, ist das Bestehen von Sachverhalten.

(What is the case, the fact, is the existence of atomic facts.)

-Ludwig Wittgenstein

Wittgenstein was a fascinating weirdo, but in the second proposition to his only (seventy-five page long) contribution to the world of philosophy and logic (the Tractatus Logico Philosophicus) he wrote the quote above. He wasn't denying art, religion, myth, but when speaking of absolute truth there are facts (atomic and otherwise) and then there is everything else.  Stay in there, it gets less boring real soon...

Basically he went against metaphysics (sort of) and Plato, et al and piled on a bunch of stuff about words and the world and truth functions (like actual math functions but with words) and examining the world using language. If any of the above grabs you: search "atomic sentence" and there's a whole world of true/false wordy-math formula semantic whatever. Anyway, Wittgenstein argued for unalterable objects/forms in direct opposition to eastern philosophy where Forms are ever changing, relative substances in a constant state of flux (sounds just like radioactive elements becoming different substances by adding/losing electrons and particles through decay. Think back to the last post about changing the dime's silver "form" to different isotopes 107, 108, 109 and 110. Flux. Change. Pretty much the opposite of Wittgenstein's ideas, but my quest to see atoms isn't.

Anyway, Wittgenstein claimed he solved all the problems of philosophy(!) so there's no need to continue in that vein. Here's an Atomic Facts of my own: I've seen the trails left by alpha, beta and gamma particles with my cloud chamber. This was covered in one of my previous posts. Think of the nuclear cloud chamber like standing in fog and watching bullets zing past you ripping lines through the fog. Cool-but I want more!

This is where my new toy comes in: a radioscope / sphinthariscope. A radioscope is a screen with zinc-sulfide paste smeared on it. It also has a magnifying eyepiece attached. You hold it up to alpha emitting radioactive objects to see tiny flashes of light when the alpha particles hit the zinc-sulphide crystal and form a phosphor (not to be confused with the chemical element phosphorus). It glows in the dark, well actually it scintillates. 

The word sphinthariscope comes from the Greek word for scintillate or sparkle. A sphinthariscope comes with a built in piece of radioactive material to "power" it-a radioscope is the same thing but with the radioactive material removed, along with the bottom of the device so that you can plop it on top of your own radioactive materials.

For $29 you can buy one from United Nuclear-but for about $9 you buy the activate zinc-sulfide and smear it on your own homemade scope. I opted to order one first, I'll probably make one from scratch for the fun of it in the future.

William Cooke made/discovered the first spinthariscope when using a phosphor screen to look for bits of radioactive material he spilled on the floor (been there-done that). He was lighting the screen with an even about of materials, but crawling around on the floor let him see tiny amounts of (alpha) radiation as individual flashes-not just an even glow. 

They became popular novelties in the early 1900s to 1950s: nice brass ones that people took to fancy dinner parties were the "in" thing. The famous Lone Ranger Atomic Ring was a later one that tons of kids received after making their Kix Cereal boxtops in. Then the fad waned.

So how did my radioscope work?

At first there was nothing, but after about ten minutes in a dark room I could see the alpha sparks. My eyes took time to adjust, but the zinc-sulfide coating glows in the dark for a few minutes as well.  At 6400 ISO with a fast f/1.8 lens I couldn't photograph them. Digital camera: 1, human eyeball: 1.

My uranium ore had random green flashes like looking out at a vast field and watching for fireflies to flash. There were some sideways "zingers" and bigger, smeared flashes like lightening behind clouds.

As "hot" as my uranium is to my Geiger counter (which measures beta, gamma and x-ray) there wasn't too much alpha going on. It was nice and subtle and I could have watched for hours, but I didn't like having uranium two inches from my face blasting intense radiation into my eyeball like some brain cancer inducing Medusa.

I moved my radioscope off the pile of uranium and plopped it on top of my little piece of Americium radioisotope 241 (AM-241). AM-241 spews out lots of alpha and a fair amount of gamma radiation. It's what ionizes the chamber inside many cheap smoke detectors: smoke particles block the alpha particles (they're weak) and trigger the alarm.

The verdict with Americium? Wow!! At first it was a dense, waving matrix of corruscating green dots like an old computer monitor from the 1980s that was being reflected in a wavy lake at night. Green dots pulsating, then the dots would surge and swirl like a Hindu mandala (which metaphysically symbolize the universe-Wittgenstein would not approve). 

Imagine the pattern on m my kilim rug, if the rug was hanging on a clothes line and the wind was blowing it toward and away from you in billowing ripples. Mesmerizing!

Sometimes it looked as though the dots were fruit flies or tiny gnats swarming (if gnats glowed in the dark). 

So, while the cloud chamber I built was like having bullets cut trails through fog, this radioscope is kinda like driving a fast car with your headlights off through a pitch black field and having fireflies splattering on the windshield...plus swirling and pulsing like a car wash on that windshield. I have lots of experience with glowing insects on my vehicle (still no idea what the one I took a photo of above was).

The surging and receding coruscating waves appear to be just like the magnetic ferri fluid (iron particles in liquid showing the magnetic field). The lapping waves of radiating particles being emitted in all directions (but viewed as they hit the flat bottom of the radioscope). 

In this flower photo the red tips are like the green alpha dots. By their speed, number and brightness you can infer many things (like the yellow paths). The charge of alpha particles was first investigated with a sphinthariscope, and research on the charge of electrons was furthered by its use; along with the correct form of atoms and their nucleus.

Imagine instead of black magnetic fluid outlining a magnetic field, green dots outlining a field radiation-smashed against the flat viewing window of my radioscope.

With these two easy to make/cheap to buy devices I've seen the paths of radioactive particles and partially how the radiate.

I think I can see the particles too! Meow.

see atomic particles with your own eyes

So you wanna see atomic particles with your own eyes huh? Here's how to do it easily!

Just build a nuclear cloud chamber...for around $7.

Cloud chambers let you see paths left by radioactive particles as they pass through a supersaturation of alcohol vapor. Vapor trails are formed when the radiation ionizes the alcohol mist super-cooled and formed by dry ice under the aquarium while the top of the aquarium drizzles the propanol (very pure rubbing alcohol you must never touch, or Everclear grain alcohol would probably work, as would methyl alcohol like Heet fuel additive). I went with a $7 bottle of 99.9% pure rubbing alcohol. Caution: the 70% stuff at drugstores won't work.

Alpha particles, and beta and gamma rays leave different looking trails in the mist; as do muons, positrons, cosmic rays, electron collisions;--basically ions. X-rays, bremsstrahlung (braking) radiation and annihilation radiation arising from positrons interacting with electrons basically behave like gamma rays.  Some trails are long and thin, some are short and fat, some branch out like lightening: each path can tell you the exact type of particle that just whizzed by! Yes, you can actually see the tracks they rip through the mist. You can even use a strong magnet and "bend" the path of some particles.

What I used: 10 gallon aquarium; metal roof flashing; stiff wire/coat hangers; styrofoam block; socks; wire to use as tie-wraps; 99.9% rubbing alcholol; DRY ICE and some radioisotope AM-241 from an ionic chamber type smoke detector ($5 at any store). AM-241 is Americium (pronounced Amer-eh-SHE-um). You'll see the Am-241 in the video, it's just a flat silver disk that is INSANELY RADIOACTIVE, yet it mostly shoots out 

Don't get confused AM has a number of 95 on the Periodic Table, but this is one of its isotopes (241). Am-241 is so radioactive that all the "harmless" alpha particles is shoots out are so plentiful it actually damages the crystal structure of the element itself! This is like the damage that radioactive particles can do to your DNA to cause cancer. In addition to tons of alpha particles it also emits some gamma particles as well. My Geiger counter can't see alpha particles--just beta, gamma and x-rays and even so it reads around 300 clicks per minute! 

MANY PEOPLE ONLINE SAY THAT AM-241 FROM A SMOKE DETECTOR ONLY PUTS OUT A FEW GAMMA PARTICLES AND THE REST IS SAFE ALPHA. THEY OBVIOUSLY DON'T OWN GEIGER COUNTERS AND CANNOT ANSWER WHEN YOU ASK THEM TO QUANTIFY THE GAMMA RADIATION. 

So do your own homework, buy a $99 Geiger counter (I use a GQ GMC-300e Plus) and don't believe everything on the internet, it can get you killed. At 300cpm what is dangerous gamma particles in this piece of AM-241 is only slightly worse than two of my old glow-in-the-dark wristwatches from the 1930s. Still, the danger is there.

BUILDING THE BEAST

Here's how I did it. Cut a recess in a foam block to hold the dry ice.

Make a wire frame inside an aquarium to hold the socks that we'll douse with 99.9% rubbing alcohol. The long pieces will go near the glass bottom. The aquarium will be upside down with the socks at the top when the unit is working.

Put the socks on and tie them with thin wire. Rubber bands will melt from the alcohol and break from the dry ice. Just use wire bread bag wraps if that's all you can find.

The aquarium's glass bottom is now it's glass top.

I fit the the aquarium on the glass block so it was air-tight and put a piece of THIN metal roof flashing between the dry ice and the inside of the cloud chamber. It looks black here because I had it covered, but it didn't work so I uncovered it. In the video it's bright shiny metal.

I put the dry ice in the hollowed out recess in the foam block. I doused the socks with alcohol. Put the AM-241 on the metal plate. I put the metal plate on the dry ice and the aquarium over everything.

Next I added a light bulb on top of the glass carefully since these 99.9% alcohol vapors are highly inflammable. The light bulb was to add WARMTH to the top of the aquarium while the bottom was super-cooled by the dry ice. This creates the fog of alcohol vapors at the bottom for the particles to leave trails through.

In the video (which gets better halfway through because I re-position the light) you'll see a half-sphere dome of fog over the AM-241 disk and a flower-like cascade of alpha particle trails shooting off the disk. The unit only worked for about 10 minutes after 2 hours of trying. Oddly, even though everyone says it needs to be airtight--the unit only started working once I gave up and started to dismantle it. Once some warmer air hit the inside the fog formed and I started seeing trails!

This could mean that the whole aquarium was too cold. At one point I put a bucket of hot water on top of the aquarium to increase the temperature differential, but it didn't seem to help. I filmed it for a few seconds, and then spent a few minutes silently watching with a smile on my face. 

Almost everything I scavenged for free, including the smoke detector's AM-241. The 99.9% rubbing alcohol was $7 and all gone when I was done. I got the dry ice from the Melvindale Public Library where I work: we had an open house and children's bookmark drawing award ceremony and we had dry ice left over from the ice cream we served. I knew that we'd have dry ice left over, so I ordered the alcohol and built the nuclear cloud chamber a couple weeks before the event. So I guess this is a $7 cloud chamber.

And that's how you can "see" atomic particles. It's a lot more fun than those golf-ball diagrams in your textbooks and tinker toy balls and connectors: like Coca-Cola this is the REAL THING; and it won't give you cavities...but it might give you radiation poisoning...