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Solid State Universe
I can understand how an atomic bomb works.

And I guess I can understand how a hydrogen bomb works as well.

But how would a neutron bomb function?

Wouldn't an explosion of neutrons be some sort of matter wave spreading outwards?

That doesn't even sound like it would work.
SIP
A neutron bomb is a thermonuclear bomb that has a shell as well as several other parts made of chromium or nickel and uses tritium as its primary explosive that thankfully only has a half life or I think 12 years. These materials are used because it only allows wide spread proliferation of the neutrons during the explosion.

Basically its used to throw heavy bombardments of neutrons at a target primarily ones that are armored and might survive any other type of attack. The ionized neutrons go right through the armor and cause massive amounts of radioactive damage to anything inside thats biological i.e. Humans, Its not necessarily an instant kill type bomb, rather dependent on were you are when it goes off it might be a rather slow (very horrible) death.

Yes a wave of highly ionized neutrons that will react with another molecules nucleus causing mass cell apoptosis and general genetic mutation leading major organ failure and death.
Solid State Universe
But would it have he same range as a thermonuclear device?
Ron
Hi SSU, SIP,
I believe the point of a Neutron bomb is to minimize the blast range, but , as SIP said, maximize the neutron bombardment. In any fusion type weapon, besides the blast itself, neutrons are the most dangerous 'fallout'. By adding other elements to increase the neutron output, the structural damage is limited, but the human damage is maximized. So your question of range depends on what type of damage you are referring to.
I personally find the amount of thought put into developing this type of weapon quite disturbing, although in war it makes perfect sense. This is one scary world we live in.
Take care,
Ron
Solid State Universe
Well... I can imagine using a 'tactical' neutron bomb against tanks, but I can't really see how the damage compares to thermonuclear.

How much material is required to create a TA radius of 1 kilometer?

It doesn't even seem like it would be that possible.

A 'matter wave' of mass particles shouldn't have the same range as the heat released by a proper nuclear detonation.

I guess there just comes a point where you start to wonder if some of this stuff is even real.

Ron
Hi again SSU,
Although neutrons are massive, being charge less they can pass through what may appear dense on a macro scale, but in reality is not. The mass distribution in an atom is limited to the nucleus. The electron orbits, however, keep the nuclei of multiple atoms separated so far apart as I've heard it put 'a grain of rice in the middle of a football field'.
Rutherford's famous back-scattering experiment's results were so surprising to him he was quoted as saying something like 'It was like shooting a cannonball at a piece of tissue paper and having it bounce back!' when he happened to hit a nucleon head on.
Later,
Ron
Solid State Universe
No... you're missing my point entirely.

If the majority of the energy of an atomic bomb is released as light and heat...

How can you build a bomb designed to release an infinitely more massive wave of matter thats expected to expand outwards along the same lines?

It would be like watching a shell of matter expand outwards, but it should rarify as it expands.
SIP
Yes it should become increasingly rare as the neutrons spread out.

I guess the question is

1. What is the original amount of ionized neutrons projected
2. How many ionized neutrons per nano meter ^3 (or whatever your choice of measure) are there in the first sec of the initial blast radius.
3. At the 2nd sec. what is the density of ionized neutrons taken at a 2nd location chosen in proportion to the speed the particles travel.
4. Finally how many of these particle do you need per nano meter^3 to cause substantial damage to a living cell?
Solid State Universe
Well, the neutron bomb in generated basically by removing the u-238 jacket from a fission bomb.

However, these neutrons are required to sustain the reaction to the point where the chain reaction occurs in the U-238, releasing heat and light which are the main destructive components.

A pure neutron bomb... well, lets see.

Something in this just doesn't ring true.

I'm beginning to think that a Neutron Bomb is about as real as Red Mercury.

carbonlife
A neutron bomb is merely a mini-H bomb rigged to enhance the neutron output.

Neutrons are heavy uncharged particles, which means they can pass through thick armor or lead rather easily, unlike gamma rays.

Neutrons are selectively absorbed by light elements such as carbon which form living matter, whereas other forms of thermonuclear radiation ( alpha, beta, gamma ) are selectively absorbed by heavy elements.

Many years ago, one of the popular science magazines published a picture taken with a neutron camera, of a brass candelabra with candles, sitting inside a lead-brick enclosure. The neutrons went right through the lead and brass, which looked ghostly on the pictures -- but the neutrons were selectively absorbed by the organic material in the candle wax, which looked dense on the neutron photo.

In other words, energetic neutrons can pass through lead and brass without losing much energy or momentum. Having passed through the lead [or armor] unimpeded, the neutrons then expend their momentum and energy when they hit something organic, such as beeswax or human tissue, knocking loose electrons, ripping up molecular bonds, and basically disrupting the life-chemistry of anything living. When a neutron strikes an atom of a light element, the result is a shower of secondary ionizing radiation, which causes damage just like any other radiation.

Neutrons also have a nasty habit of traveling through the ground and reflect off the water table and off bedrock, killing anyone in an underground bunker. Other types of radiation ( alpha, beta and gamma ) don't have that capability. The tendency of neutrons to go right through armor and bounce around corners makes them attractive as bunker-busters, because modern bunker systems have blast doors at intervals, and dog-leg passages that can run for miles underground.

Unfortunately, bunker systems tend to be built under large civilian cities -- Saddam's bunker network was built under Baghdad ( pop. 7 million http://en.wikipedia.org/wiki/Baghdad ). If the US had had bunker-busting neutron bombs at the time they invaded Baghdad based on fabricated information about WMD, taking out the bunkers could have killed millions of Iraqi civilians through neutron flash and seismic shocks.

A neutron bomb does NOT ( as commonly mis-reported ) kill people and leave structures intact. A neutron bomb is a mini-hydrogen bomb; and produces all of the usual destructive effects of an H-bomb ( heat flash, gamma radiation flash, supersonic blast wave, over-pressure wave at greater distances, and radioactive fallout plume reaching high altitudes ). A neutron bomb actually produces MORE radioactive fallout than a 'regular' tactical-H-bomb of the same yield, because most of the radioactive fallout of a 'regular' mini-H-bomb comes from neutrons that induce persistent radioactivity in pulverized material.

A neutron bomb simply has 'enhanced kill' of living tissue hiding inside armor or inside bunkers or behind berms. The enhanced kill comes about because a higher percentage of the bomb's energy comes out as energetic neutrons, whereas in a 'normal' H-bomb more of the energy would come out as blast / heat / X-rays and whatnot. A normal H-bomb is surrounded by metals that reflect neutrons back into the bomb, to increase the yield. A neutron bomb is built without the neutron reflectors, so that the neutrons can get out. That would normally cause a lower yield, but extra tritium is added to bring the yield back up to par.

When a 'normal' tactical H-bomb goes off in mid-air ( "air burst" ), most of the energy gets absorbed by air within a half-mile radius of the detonation, turning that air into a "fireball" of extremely hot plasma. That fireball then does 2 things -- it emits a powerful flash of radiant energy all the way from the infrared to the X-ray region of the spectrum, and (cool.gif the fireball begins expanding at supersonic velocity, pushing aside millions of tons of air in the process. The displaced compacted air then flattens anything in its path. After a brief interval the fireball goes dark, because the scorched air within the fireball forms brown oxides of nitrogen. Displaced air then rushes back in, sweeping up pulverized material and ash into the fireball, which rises rapidly to the stratosphere and cooks a wider area with its heat and radiation as it rises.

The surplus of energetic neutrons emitted by a neutron bomb pass right through the forming fireball and keep going until they hit something solid made of light elements, such as people cowering behind a hardened wall.

Again, a neutron bomb is a matter of degree. All thermonuclear reactions produce neutrons, whether the reaction is fission ( A-bomb ) or fusion ( H bomb ). The tritium which 'powers' the H-bomb consists simply of heavy hydrogen which has 2 extra neutrons on every atom. That's necessary because an H-bomb turns hydrogen into helium. It takes 2 neutrons to make a helium atom, but a normal hydrogen atom has none, so heavy hydrogen is used to supply the required neutrons. Some of those extra neutrons get loose as neutron radiation. A neutron bomb is simply designed to let more neutrons out.

A neutron bomb can also kill electronics more effectively at short range, because some of the neutrons are stopped by silicon in the chips, which is a somewhat light element. It doesn't take much radiation damage to kill a chip, because silicon chips have to be near-perfect crystals in order to function as high-performance semiconductors. Anything that rips up the crystal structure even a little ruins the chip.

It's a myth that neutron bombs are clean, humane, or environmentally friendly. Their destructive effects are NO LESS than a tactical hydrogen bomb of equivalent yield. It's also a myth that neutron bombs can kill people in a WMD facility without releasing deadly spores, causing a nuclear meltdown or whatever. A neutron bomb might easily do both, especially if the targeting intel is sketchy or wrong. It takes an extremely high dose of radiation to kill anthrax, compared to what kills humans -- a strike near enough to crack open the containment and release the spores might not kill the spores.

A neutron bomb also might not stop someone with their finger on a retaliatory button. A person can receive many times the lethal dose of radiation and soldier on for several hours, until they start vomitting uncontrollably, bleeding internally and whatnot. http://en.wikipedia.org/wiki/Radiation_sickness

In other words, neutron bombs are not a 'magic bullet' to instantly wipe out terrorists who have a vial or a suitcase nuke or whatever. As with any tactical nuke, the radius of total destruction is limited, and the neutron kill radius isn't much higher. Neutron bombs aren't fully scalable, because neutrons are absorbed by atmosphere within several miles, regardless of how powerful the bomb is.

Because neutron bombs aren't a magic bullet and aren't at all 'surgical', they can have extreme political fallout when their use is provoked by disinformation or misdirection. A single neutron bomb could literally make tens of millions of enemies around the world, some of which might have access to a loose nuke or two to retaliate with -- making it hard to tell who was behind the loose-nuke attack because the former Soviets misplaced so many. For that reason, increased lethality needs to be matched by increasingly powerful intel, since modern opponents ( particularly Al Qaeda ) are adept at baiting the US into making enemies, using false trails of misinformation matching what the commander-in-chief wants to believe. This will remain a problem no matter who's the commander in chief or which party they're from. Congress has no constitutional power to rein in a US president once Congress approves a declaration of war, even if the president decides to use a nuclear weapon in response to an imagined threat. Congress has just signaled that they can only pass non-binding resolutions of opposition to whatever a president might choose to do. Several recent presidents have responded to situations with threats that no options were off the table [including nuclear], without needing approval from Congress to place the world on notice that a president was weighing unilateral use of a nuclear weapon.

None of the above information is classified -- it's all basic physics, because an H-bomb uses the same operating principle as a star. For quite a bit of additional information see the Wikipedia article at
http://en.wikipedia.org/wiki/Neutron_bomb

--
"I don't know with what weapons World War 3 will be fought, but World War 4 will be fought with sticks and stones. -- Albert Einstein [ a guy who understood chain reactions. ]

""Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius -- and a lot of courage -- to move in the opposite direction." -- Albert Einstein.
Solid State Universe
Wow.

That was a lot of information.

But aside from being a 'dirty weapon' in several regards, I was wondering about specifics.

For example, suppose we've got 2 kilos of tritium for our nuke. Whats the effective yield for this explosion and whats would be the lethal radius?

Tritium has 3.02 grams per mole.

This gives us 662 moles of tritium in our 2 kilo sample.

Which should be about 3.98 * 10^26 atoms.

But we're only looking at 2/3rds of this mass having the potential to become a 'neutron bullet'.

So there's about 2.65 * 10^26 neutrons available in two kilos of tritium.

Anyone care to work out the calculations for the blast radius of this neutron 'matter wave'?

(Fixed calculations. Very very stupid of me.)
N O M
QUOTE (SIP+Jan 24 2007, 09:05 PM)
1. What is the original amount of ionized neutrons projected

ionized neutrons? What are they?

neutrons are neutral. You could remove a negative charge (electron) from a neutron, but you would be left with a proton.
SIP
OOps sorry damn that looks dumb. sorry im tired as hell today ive been up for like two nights study for NET test i might say some dumb things in the next 24 hrs so sorry ahead of time.
SIP
I think I got ionizing radiation, fast neutrons, thermal neutrons, or slow neutrons whatever all mixed up in my head when i was thinking about that post sorry. sad.gif
N O M
QUOTE (SIP+Jan 25 2007, 12:31 AM)
i might say some dumb things in the next 24 hrs

You will fit in quite well in most of the threads on this forum then laugh.gif
Solid State Universe
Well, this is the implication, isn't it?

An N-bomb burns tritium and deuterium with a small fission explosion which release the extra neutrons, leaving just a single hydrogen atom and an expanding sphere of neutrons.

Hmmm... like tiny bullets that only bind to elements lighter than iron or nickle.

Still, it seems somewhat extreme to imagine the mechanics behind the blast.
graham7773
lost the question but it was "how much area is affected by a neutron bomb detonation?" Bigest one I have heard of was a US construct with a 100 mile radius of 100% fatalities. In other words, the biggest city in the world would be devoid of life after such a detonation. Even some small countries would have zero living persons after the use of such a weapon. Maybe that is why the USA has reported the dismantling of its neutron weapons. Did they really do that? It seems that it would be a very efective deterrant to agressors. The really frightening aspect of this is that the area of destruction of life is 31,400 sq miles(approximately)
AlexG
QUOTE (graham7773+May 15 2012, 03:46 PM)
lost the question but it was "how much area is affected by a neutron bomb detonation?" Bigest one I have heard of was a US construct with a 100 mile radius of 100% fatalities. In other words, the biggest city in the world would be devoid of life after such a detonation. Even some small countries would have zero living persons after the use of such a weapon. Maybe that is why the USA has reported the dismantling of its neutron weapons. Did they really do that? It seems that it would be a very efective deterrant to agressors. The really frightening aspect of this is that the area of destruction of life is 31,400 sq miles(approximately)

I realize it's your first post, but responding to a 5 year old dead thread makes you look a little silly.

As for your statement
QUOTE
Bigest one I have heard of was a US construct with a 100 mile radius of 100% fatalities


Please supply a citation, cause I'm calling this one bullshit.
laf47909
The information in the posts has been great, but I have some specific questions.

Would a neutron bomb had been effective against Bin Laden and the terrorists while they were bottled up in Tora Bora?

Is there a signature such as trace elements which identify a neutron bomb from the US versus one produced elsewhere?

I believe that the neutrons from a neutron bomb would convert the lighter elements, such as carbon and oxygen, in a human body to their radioactive counter parts. Would this cause radiation sickness in people who come in contact with people who have been exposed to a neutron bomb detonation?

Thanks for all who can help with this info.
boit
If the half life of the radioactive material is just 12 years, then this is a type of a 'clean' dirty bomb. Almost green you'll say. What better, it doesn't destroy infrastructer. Will be unpopular with terrorists who love pyrotech (and corrupt politicians wanting to award contracts in the aftermath). Rebuilding is a costly business.
dhcracker
So your saying my lead lined bunker needs a coating of candle wax to keep out neutrons?? Jeez what next lol

You know I remember the 80's well we were certain of war we just hoped it wouldn't go nuclear, Red Dawn seemed like a real possibility to us as we were practicing ducking and covering under our school desks.
boit
QUOTE
Ducking and covering under our school desks . . .
As someone rightly pointed out elsewhere in this forum, 'ducking and cowering under the desk following a nucler attack is good for kissing your a$$ goodbye and nothing else.
dhcracker
QUOTE (boit+Sep 23 2012, 05:00 PM)
As someone rightly pointed out elsewhere in this forum, 'ducking and cowering under the desk following a nucler attack is good for kissing your a$$ goodbye and nothing else.

I remember telling my teacher that once, during a drill I told them if it was the real thing I wanted to go outside and watch the missiles come in cause we were all going to die anyway... a few kids started crying lol.
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