JamesDJarvis
First Post
interesting trivia- Lasers are loud.
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Energy Weapons VS Ballistic Weapons
- Thread starter Ralts Bloodthorne
- Start date
Pbartender
First Post
Plane Sailing said:
Having a great time with my kids over two and half weeks of Holiday vacation.
Sorry guys. You want it, you got it. I'll be right back with a lengthier post, but first let me address this...
JamesDJarvis said:
No, normally they are not.
The cooling systems for lasers may be loud or the power systems for the lasers may be loud (especially if you are using a large bank of capacitors for a pulsed laser), but the laser itself very rarely makes any noise.
A pulsed laser might make a noise ranging anywhere from a faint tick to a dull thud when its capacitors discharge, depending on how big the caps are, and how much power you're discharging. That noise is the sound of metal components inthe power supply quickly expanding and contracting as they heat up and cool down with the sudden pulse of electricity.
The material the laser beam hits might make a noise -- sizzling, crackling, a pop, or any other noise, depending on the amterial -- as it burns, melts or boils.
Theoretically, a powerful enough laser beam could make a cracking noise much like a lightning bolt, as it super-heats the moisture in the air it travels through.
In general, though, your average laser is pretty quiet.
JamesDJarvis
First Post
"Lasers are loud" might not have covered it enough: Some lasers designed for a combat role are themsleves surprisingly loud. They do make a cracking noise much like a lightning bolt as it super-heats the moisture in the air it travels through. Some of the engineers I know have reported a "boom" that isn't the powerplant or the target being hit either.
Folks forget we have, at least in testing and very limited use, all sorts of energy weapons. They aren't sci-fi mumbo-jumbo. Systems like Zeus- mine destruction, Thel - anti-missle, the ADS "Pain Ray" do exsist.
Folks forget we have, at least in testing and very limited use, all sorts of energy weapons. They aren't sci-fi mumbo-jumbo. Systems like Zeus- mine destruction, Thel - anti-missle, the ADS "Pain Ray" do exsist.
Pbartender
First Post
JamesDJarvis said:
Very cool stuff... more 1940's ray-gun pulp sci-fi type stuff than anything else.
All right, everybody... Here we go:
Author's Note: As much as possible I'm going to stick to science that the layman can understand. This information is dervied from the firsthand experiences of an operator* and technician working at a large US Gorvfernment High Energy Physics Research Laboratory. These diatribes will focus on practical usage, real-world logitistics and the everyday technical aspects of building and using the sorts of weapons Science Fiction and Science Fantasy often refer to as "energy weapons"... Theoretical physics is useless to a soldier on the battlefield, if his weapon can't realistically neutralize his enemy.
LESSON 1: Ion Cannons
An ion cannon is simply a machine that shoots charged particles. The particles could be electrons or protons, or any number of ionized atoms or molecules. The particles could even consist of antimatter, so long as they contain a charge -- positrons or antiprotons, for example -- but I'll talk about antimatter more later.
It's the charge that's the important part for an ion cannon. So long as the charge is present, you can use an electric field oscillating at radio-frequencies (a glorified radar or radio transmitter) to accelerate those particles to near the speed of light. The charges also allow you to use magnetic fields to tightly focus the beam of particles and steer the stream in a particular direction.
An ion cannon inflicts damage by bombarding a target with high-energy particles. The particles collide with the material of the target, typically knocking the molecules and atoms of said target into little bits. Macroscopically, very little damage is dealt to the target. The primary byproducts of the impact are heat, radiation and a shower of assorted, very short-lived, sub-atomic particles.
In combat situations, and assuming the ion cannon was powerful enough, equipment will take small amounts of damage from ion cannons, that will usually look like super-heated burns, scorches and/or melted spots. Additionally, the equipment will be radioactive for anywhere from seconds to hours or days. Personnel would possibly suffer from burns and would more likely suffer acute radiation exposure from the short-lived byproducts.
THE STAR WARS FALLICY: ION CANNONS WILL NOT DISABLE ELECTRONIC DEVICES WITHOUT DAMAGING THE EQUIPMENT.
Really, in the end, an ion cannon is just like any other ballistic weapon, except that you're using an extraordinary amount of extraordinarily tiny bullets traveling extraordinarily fast.
Ion cannons have two important numbers regarding their damage capability... The number of particles you are tossing out, and the energy that you are tossing them out at (normally measured in electron-volts). Currently, it is not not uncommon to see particle accelerators (ion cannons) that can accelerate their beams into the gigaelectron-volt (GeV) ranges. The amount of particles emitted by modern particle accerator is normally measured in the billionths or trillionths of grams per pulse (about 10^10 to 10^14 particles per pulse).
The major shortcomings of using an ion cannon as a weapon currently are required power, required space, damage output, range and penetration.
Power... The laboratory I work at, Fermi National Accelerator Laboratory, has three seperate power sub-stations for the sole use of the lab. Electricity is the lab's single largest budgetary item. The power amplifiers used to accelerate our proton beams are rated anywhere from 250 KW to 5 MW. The various accelerators use anywhere from seven to eighteen of these power amplifiers to run the RF cavities that accelerate the beam. Any useful ion cannon would require it's own small powerplant to fire it. The power plant aboard a nuclear aircraft carrier might be sufficient.
Space... Fermilab owns a chunk of land about four miles by three miles. Our smallest accelerator (400 KeV) is a straight line several hundred yards long. Our largest (1 Tev or 1000 Gev) is a circle four miles in circumference. This doesn't count the space require for the equipment, workshops, tools and support personnel (2,000+ employees) to run and maintain the machines.
Damage output... From very personal exerience, a beam of protons accelerated to 120 GeV at about 7x10^14 particles (about 7 billionths of a gram) per pulse, firing one pusle every two seconds will put a pinhole through 1/8th inch aluminum in about an hour or two. Given several months, that same power and intesity can draw a scorched and bubbly line a fraction of an inch deep across a plate of stainless steel. By the same repect, the pinhole will be radioactive to the tune of a few tens or hundreds of mrem/hr hour, for a few hours (fairly safe), and the scroched line will radiate at 2 or 3 rem for several weeks or months (potentially dangerous).
Range... All the particles you use in an ion cannon are necessarily the same charge. They must be, in order to get them all travelling in the same direction. Unfortunately, as we all know from high school science class, like charges repel each other. Once the ion beam leaves the "barrel" of the "gun", the ions no longer have any active focusing. The ions push each other apart, and the beam very quickly disperses, like a shotgun shot, or a flashlight beam. Even in vacuum, after a few hundred yards, the beam is nearly useless. In atmosphere its far worse.
Penetration... Ion cannons are very easy to defend against. An inch or two of steel will stop dead the beam of any modern ion cannon. The same amount of lead backing will soak up any of the radioactive byproducts. Simple ablative armor would be extremely effective against even future versions of ion cannons. Alternately, if you want something more spectacular, you can protect yourself from an ion cannon with a strong magnetic field. The charged particles get caught spiralling around the magentic field lines, until they sucked into either pole of the magnet, where you lay out some thick shielding. That is, essentially, what happens when a solar flare (ionized gas) hits earth's magnetic field, producing the northern lights.
Given the proper technology, an ion cannon could make a feasible weapon. However, it would likely be more trouble than its worth, and far less effective than ballistic or explosive weapon using the same technology.
The best example I've ever seen of a fairly realistic ion cannon is from the computer game, Homeworld. The "Ion Cannon Frigate", I believe its called, is a starship built around a linear particle accelerator. The linac itself provides the primary spine of the ship, takes up most of the ship's bulk and can only be aimed by reorienting the ship.
More to come...
*Operator in the Rifts RPG occuptional character class sense, rather than the telephone switchboard sense.
Skrittiblak
First Post
Sorry to bump a dead thread - but I could have sworn this was longer!
Has the rest of this thread been erased in the sands of time?
CRAP. There was a really great thing that Pbartender wrote on lasers. I think its gone!
Has the rest of this thread been erased in the sands of time?
CRAP. There was a really great thing that Pbartender wrote on lasers. I think its gone!
Storyteller01
First Post
Awhile ago several months worth of files were lost (I don't remember the exact reason).
Pbartender
First Post
Skrittiblak said:
Yep... there was a lot more to this thread. Looks like it all got lost during the crash last spring. They had to revert to a previous backup of the boards and the last one was from right around Christmas time. A couple months worth of posts were forever lost, if I remember correctly.
Skrittiblak
First Post
Google Cache Is Awesome!!!!!
LESSON 2: Antimatter
Antimatter is a particle of any type matter that has the sign of one of its basic properties reversed. In every other way, they are identical to their anti-partner. An antielectron (a positron), for example, has a positive charge, instead of a negative charge. Any type of particle, even neutrally charged ones such as neutrons, can have an antiparticle, since the electrical charge is not the only possible value that can be reversed.
When a particle and its antiparticle meet, they annihilate each other in a burst of energy. This reaction reaction releases the most amount of energy per unit mass in known science. Unfortunately, the reaction, as opposed to popular belief, doesn't not always completely convert the matter and antimatter into energy. Only the lightest particle-antiparticel pairs can accomplish this. An electron-positron collision, for example, produces nothing but 511,000 electron volts worth of gamma rays. Something heavier, like protons an antiprotons, will produce, in addition to high-energy gamma rays, a spray of assorted secondary particles that decay very quickly into nuetrinos and low-energy gamma rays.
If they didn't, we wouldn't have been able to use proton-antiproton collisions at Fermilab to find the top quark or search for the Higgs boson.
An antimatter reaction is extraordinarily efficient when converting mass to energy. The less efficient reaction of the heavier antimatter particles is actually more useful in regards to both weapons and fuel. High-energy gamma rays will pass straight through most material without interacting, unless you have a lot of shielding to abosrb it. The secondary particles produced by the heavier antimatter reactions will produce more meaningful damage, especially radiation damage as they decay.
As a comparison, a nuclear fission is about 20 times as efficient as your tyical rocket fuel. Nuclear fusion is about 120 to 200 times as efficent as that rocket fuel. Matter-antimatter annihilation is 200 to 2,000 times as efficient.
Antimatter suffers from two very major drawbacks... Production and containment.
Production... Antimatter is expensive and excessively time consuming to make. Antimatter costs about $62.5 trillion a gram to produce. What's more, even Fermilab, currently the world's best antimatter production facility, can't make more than a couple trillionths of a gram in an hour, and can't collect more than a couple dozen trillionths of a gram at once. Even that amount of antimatter is practically harmless, as far as weaponry is concerned... It's not enough to put the slightest scratch in aluminum foil. Additionally, antimatter (antiprotons, at least) is created primarily by bombarding a solid target with high energy protons -- you shoot a slab of metal with an ion cannon (Remember all those secodary particles I talked about in Lesson 1? Antiprotons are some of them.) Realistically, in order to produce a useful amount of antimatter, you'll need ion cannon technology sufficient to drive the resultant antimatter weapon into obsolescence.
Containment... Antimatter, in sufficient quantities would be very, very dangerous. Even without the danger, its simply a delicate substance to work with. Practically anything it touches destroys it. Some types of it (those with electrical charges) can be contained using magnetic fields... But that would require significant power just to hold it steady. Also, it would need to be stored in near perfect vacuum, or the antiparticles would slowly wear away.
In the end, it's a matter of logistics for antimatter. It's too expensive to make, too troublesome to store, and too dangerous (in weapons-grade amounts) to use. It's the same reasons nitro-glycerin never was and never will be used as a weapon.
LESSON 3: Lasers
Lasers are just beams of light that are monochromatic, coherent and directional. "Monochromatic" means that the laser emits a single, specific wavelength of light. "Coherent" means that the light waves are all in phase, that they oscillate not just at the same frequency but at the same time. "Diretional" means that all the lightwaves are travelling in the same direction as a tightly focused beam.
So, if a the light from a light bulb is kind of like a crowd of people scattering to their various homes after a football game, the light from a laser is more like the members of a marching band, all wearing identical uniforms, marching in perfect step in a straight line.
Lasers, as focused beams of light, can have two major effects on the battlefield... First, the heat produced by the beam could feasibly damage equipment and kill people. Second, the light from the beam could blind people or sensitive optical equipment.
This is nothing new, many militaries are already experimenting with lasers for such applications.
Lasers have a few minor drawbacks, that will likely be overcome sometime within the next hundred years or so...
Size... A laser of any significant power to worthwhile damage to a target is pretty big. Most experimental military lasers are approximately the size of a refrigerator, or an outdoor spotlight (not the theatrical sort, the sort you see outside circuses, carnivals and car dealerships pointing up at the sky). Lasers of this size are currently powerful enough to shoot down a mid-sized missile.
Power... Unlike most sci-fi weaponry, lasers truly are an "energy weapon". They require no ammunition of any sort, aside from electrical power. Electrical power in very large quantities, however, if you want to deal any real damage. The anti-missile lasers currently being tested in Isreal fire a 1-10MW laser beam that's about three or four feet across, if I remember correctly. That's probably about the minimum power required to use a laser as an effective weapon.
Fortunately, both of those problems are soluble, given time.
Lasers do have one or two other quirks, that can a help or a hinderance, depending...
Line of sight... Lasers shoot in a straight line. While this makes it very easy aim the laser, it also eliminates the possibility of indirect fire. Unlike an artillery shell, missile or handgrenade, if there's something between you and your target, you can't lob a shot over the obstruction to hit something you can't see behind it.
Range... Lasers, especially powerful lasers, can have a pretty long range. The trouble is, even though lasers are directional, the beam still disperses as it travels. Since you're spreading the light over a wider area, it effectively reduces the damage the laser is capable of at longer ranges.
Tracing... Laser beams are more or less invisible. If you can see the laser beam, you're losing damage potential. This makes it hard for enemies to see where you are shooting from, but it also makes it difficult to see where you are shooting.
Continuous vs. Pulsed... A continuous laser can be turned on and left on. A pulsed laser can only be flashed in short pulses. The pulsed laser typically uses a bank of capacitors, which are charged up and then discharged to produce a more power laser pulse than would ordinarily be available with that particular power supply. The tradeoff is a series of short, more powerful pulses of laserlight, instead of a steady beam of less powerful laser light that can be swept across the battlefield or held to a particular target.
No recoil... Lasers effectively have no recoil.
Defense... Anything that can disperse light (like particluate clouds), reflect light (mirrors), or conduct and disperse heat (high-temperature alloys with heat sinks) will prove a good defense against most lasers.
In gaming terms, a pulsed laser deals more damage with the same power supply. A continuous laser deals less damage, but could be used in "auto-fire" mode to strafe across a battlefield, much like a gatling gun.
Lasers would likely be best used as point defense weapons, tracking and shooting down missiles and shells at short range as they come in, or as personal firearms, if you can develop the miniaturization and power technologies to allow it.
LESSON 2: Antimatter
Antimatter is a particle of any type matter that has the sign of one of its basic properties reversed. In every other way, they are identical to their anti-partner. An antielectron (a positron), for example, has a positive charge, instead of a negative charge. Any type of particle, even neutrally charged ones such as neutrons, can have an antiparticle, since the electrical charge is not the only possible value that can be reversed.
When a particle and its antiparticle meet, they annihilate each other in a burst of energy. This reaction reaction releases the most amount of energy per unit mass in known science. Unfortunately, the reaction, as opposed to popular belief, doesn't not always completely convert the matter and antimatter into energy. Only the lightest particle-antiparticel pairs can accomplish this. An electron-positron collision, for example, produces nothing but 511,000 electron volts worth of gamma rays. Something heavier, like protons an antiprotons, will produce, in addition to high-energy gamma rays, a spray of assorted secondary particles that decay very quickly into nuetrinos and low-energy gamma rays.
If they didn't, we wouldn't have been able to use proton-antiproton collisions at Fermilab to find the top quark or search for the Higgs boson.
An antimatter reaction is extraordinarily efficient when converting mass to energy. The less efficient reaction of the heavier antimatter particles is actually more useful in regards to both weapons and fuel. High-energy gamma rays will pass straight through most material without interacting, unless you have a lot of shielding to abosrb it. The secondary particles produced by the heavier antimatter reactions will produce more meaningful damage, especially radiation damage as they decay.
As a comparison, a nuclear fission is about 20 times as efficient as your tyical rocket fuel. Nuclear fusion is about 120 to 200 times as efficent as that rocket fuel. Matter-antimatter annihilation is 200 to 2,000 times as efficient.
Antimatter suffers from two very major drawbacks... Production and containment.
Production... Antimatter is expensive and excessively time consuming to make. Antimatter costs about $62.5 trillion a gram to produce. What's more, even Fermilab, currently the world's best antimatter production facility, can't make more than a couple trillionths of a gram in an hour, and can't collect more than a couple dozen trillionths of a gram at once. Even that amount of antimatter is practically harmless, as far as weaponry is concerned... It's not enough to put the slightest scratch in aluminum foil. Additionally, antimatter (antiprotons, at least) is created primarily by bombarding a solid target with high energy protons -- you shoot a slab of metal with an ion cannon (Remember all those secodary particles I talked about in Lesson 1? Antiprotons are some of them.) Realistically, in order to produce a useful amount of antimatter, you'll need ion cannon technology sufficient to drive the resultant antimatter weapon into obsolescence.
Containment... Antimatter, in sufficient quantities would be very, very dangerous. Even without the danger, its simply a delicate substance to work with. Practically anything it touches destroys it. Some types of it (those with electrical charges) can be contained using magnetic fields... But that would require significant power just to hold it steady. Also, it would need to be stored in near perfect vacuum, or the antiparticles would slowly wear away.
In the end, it's a matter of logistics for antimatter. It's too expensive to make, too troublesome to store, and too dangerous (in weapons-grade amounts) to use. It's the same reasons nitro-glycerin never was and never will be used as a weapon.
LESSON 3: Lasers
Lasers are just beams of light that are monochromatic, coherent and directional. "Monochromatic" means that the laser emits a single, specific wavelength of light. "Coherent" means that the light waves are all in phase, that they oscillate not just at the same frequency but at the same time. "Diretional" means that all the lightwaves are travelling in the same direction as a tightly focused beam.
So, if a the light from a light bulb is kind of like a crowd of people scattering to their various homes after a football game, the light from a laser is more like the members of a marching band, all wearing identical uniforms, marching in perfect step in a straight line.
Lasers, as focused beams of light, can have two major effects on the battlefield... First, the heat produced by the beam could feasibly damage equipment and kill people. Second, the light from the beam could blind people or sensitive optical equipment.
This is nothing new, many militaries are already experimenting with lasers for such applications.
Lasers have a few minor drawbacks, that will likely be overcome sometime within the next hundred years or so...
Size... A laser of any significant power to worthwhile damage to a target is pretty big. Most experimental military lasers are approximately the size of a refrigerator, or an outdoor spotlight (not the theatrical sort, the sort you see outside circuses, carnivals and car dealerships pointing up at the sky). Lasers of this size are currently powerful enough to shoot down a mid-sized missile.
Power... Unlike most sci-fi weaponry, lasers truly are an "energy weapon". They require no ammunition of any sort, aside from electrical power. Electrical power in very large quantities, however, if you want to deal any real damage. The anti-missile lasers currently being tested in Isreal fire a 1-10MW laser beam that's about three or four feet across, if I remember correctly. That's probably about the minimum power required to use a laser as an effective weapon.
Fortunately, both of those problems are soluble, given time.
Lasers do have one or two other quirks, that can a help or a hinderance, depending...
Line of sight... Lasers shoot in a straight line. While this makes it very easy aim the laser, it also eliminates the possibility of indirect fire. Unlike an artillery shell, missile or handgrenade, if there's something between you and your target, you can't lob a shot over the obstruction to hit something you can't see behind it.
Range... Lasers, especially powerful lasers, can have a pretty long range. The trouble is, even though lasers are directional, the beam still disperses as it travels. Since you're spreading the light over a wider area, it effectively reduces the damage the laser is capable of at longer ranges.
Tracing... Laser beams are more or less invisible. If you can see the laser beam, you're losing damage potential. This makes it hard for enemies to see where you are shooting from, but it also makes it difficult to see where you are shooting.
Continuous vs. Pulsed... A continuous laser can be turned on and left on. A pulsed laser can only be flashed in short pulses. The pulsed laser typically uses a bank of capacitors, which are charged up and then discharged to produce a more power laser pulse than would ordinarily be available with that particular power supply. The tradeoff is a series of short, more powerful pulses of laserlight, instead of a steady beam of less powerful laser light that can be swept across the battlefield or held to a particular target.
No recoil... Lasers effectively have no recoil.
Defense... Anything that can disperse light (like particluate clouds), reflect light (mirrors), or conduct and disperse heat (high-temperature alloys with heat sinks) will prove a good defense against most lasers.
In gaming terms, a pulsed laser deals more damage with the same power supply. A continuous laser deals less damage, but could be used in "auto-fire" mode to strafe across a battlefield, much like a gatling gun.
Lasers would likely be best used as point defense weapons, tracking and shooting down missiles and shells at short range as they come in, or as personal firearms, if you can develop the miniaturization and power technologies to allow it.
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