Particle Beams vs Lasers

[Stark]

First off, I'm comparing these weapons from a purely academic standpoint, comparing their performance at extreme range and their targetting flexibilty.

My understanding is that if you redirect a laser (with lenses, gravity fields or whatever) it doesn't lose any of its energy. Thus lasers are flexible weapons.

PBs, on the other hand, lose energy dramatically if redirected, and thus lend themselves more to mechanical means of training, such as turrets etc. PBs also require projectile tankage, which lasers do not.

Both weapons have the problem of beam spread. Which system would spread less over a given distance? Does beam divergence affect weapon performance in the same way for both systems?

[Peregrin Toker]

Both weapons have the problem of beam spread. Which system would spread less over a given distance? Does beam divergence affect weapon performance in the same way for both systems?

I think lasers barely spread their bream compared to neutron beams.... but I'm not sure.

[Lancer]

Both weapons have the problem of beam spread. Which system would spread less over a given distance? Does beam divergence affect weapon performance in the same way for both systems?

I think lasers barely spread their bream compared to neutron beams.... but I'm not sure.

the problem with lasers is that any lens used to focus the beam will have imperfections that cause the beam to lose focus over distance. And to redirect them, you have to use either gravity-manip or something that can somehow withstand temporarily absorbing a lot of energy, because some of the beam's energy will be lost into the reflecting material.

However, with particle beams, you need to overcome the KE of the particles in order to totally redirect the beam, and the intrisic repulsion from the particles in the beam will spread it out over distance.

Personally, I'd go for neutron beam weaponry. Lotsa KE, very hard to redirect via magnetic fields, and very low repulsion.

[Winston Blake]

I think lasers are more feasible/cheaper/simpler but PBWs are potentially more powerful, and more penetrating.

I base a lot of my scifi directed energy weapon views on this article:
http://www.airpower.maxwell.af.mil/airc ... berds.html

[1337n1nj4]

Ooooh I like that.

That's actually a damn good idea, to use different types for atmospheric and spaceborne weaponry.

[Arrow]

You also have Free Electron Lasers. They could most likely give you the same effects as a heavy element particle cannon with a lower input energy cost. Over course you would probably have to turrent mount the sucker (at those power levels, the beam would destroy a mirror).

[Isolder74]

Generally a Particle beam has more penetrating power. Both have different means of causing damage. A particle beam uses KE to cause damage. The Laser tends to have to burn its way through the target to do its damage.

I'll go into it with more details later.

[18-Till-I-Die]

Isnt an ion cannon/beam a particle beam?

And what could one do, exactly?

[Ma Deuce]

Isnt an ion cannon/beam a particle beam?

Yup.

And what could one do, exactly?

I have no idea. I imagine with sufficient power, it could be quite destructive (as would be the case with all particle weapons), though I'm not sure if it would have the same EMP-like effects that Star Wars ion cannons do (it should also be noted that contrary to popular belief, SW Ion Cannons do in fact inflict physical damage to their target. Far less than turbolasers, but physical damage nonetheless).

[18-Till-I-Die]

Arent lasers measured in watts? And hwo does that come out in joules?

And forgive me if this is going off-topic.

[1337n1nj4]

Watts = joules/second

[18-Till-I-Die]

Watts = joules/second

Thanks

[Shroom Man 777]

Hrmmm....aren't particle beams the same or similar to plasma beams?

[1337n1nj4]

Similar.

Plasma is just hot ionized gas, so in a sense it is like the charged particle beams described in that article for atmospheric use (lightning is also a form of plasma, IIRC, so it's a similar effect).

[Shroom Man 777]

Its a poor man's particle cannon, aye? So before we go to full uber particle cannons, we can have plasma weapons.

[Shinova]

A really powerful ion cannon would probably look something like the type you'd find in the Command and Conquer series.

[Crown]

You also have Free Electron Lasers. They could most likely give you the same effects as a heavy element particle cannon with a lower input energy cost. Over course you would probably have to turrent mount the sucker (at those power levels, the beam would destroy a mirror).

Aren't FEL's just the way the LASER beam is generated? I mean they are still LASERS in fucntion? Or are you saying that they get a similar LASER power level as a HEP beam? Just a little unclear on what you are saying is all.

[Winston Blake]

Yes, FELs are lasers. No, i don't know what he meant by "same effects as a heavy element particle cannon".

Also, i'd imagine that an 'ion beam weapon' would be no different to a particle beam weapon. As described in the article i linked to, proton (ie hydrogen ion) and electron particle beams are pretty much the same in destructive effect.

A 'plasma beam weapon' might be a proton CPB and electron CPB mixed together for a net neutral charge. Kinda like a Quasi-NPB. I guess technically you could say it's a hydrogen plasma...

Anyway, i think lasers tend to deposit their energy on the surface of a target, which leads to nasty ablation that limits a laser's effectiveness. OTOH PBWs, being more penetrative, deposit their energy in a kindof volume within the beam area. The same might apply to gamma-ray lasers, i've noticed that they've been described as very penetrative in the "Questions about lasers" thread.

AFAIK one of the major differences between lasers and PBWs is optical effects like reflection/refraction and transparency. Since air is transparent to IR/visible range lasers, but not to particles, a practical endoatmospheric PBW needs a special-purpose laser to fire before it does, to heat and therefore rarefy the air atoms. Also, armor could conceivably be made to reflect/refract the laser frequency range needed to effectively transmit through atmosphere, but that wouldn't apply to particles (at least the boring normal ones like protons/electrons/nuclei rather than Trek funkyons).

To the original poster:

My understanding is that if you redirect a laser (with lenses, gravity fields or whatever) it doesn't lose any of its energy. Thus lasers are flexible weapons.
PBs, on the other hand, lose energy dramatically if redirected, and thus lend themselves more to mechanical means of training, such as turrets etc. PBs also require projectile tankage, which lasers do not.

From a purely academic standpoint, i agree with you. But RL SDI-type lasers/PBWs were supposed to engage targets really far away, meaning you only ever need tiny beam adjustments (for both of them). Because (realistic) lasers would require lenses, PBW 'pointing and tracking' via magnetic fields may actually be more efficient.

Also, the particle "tankage" would be very small, considering we're talking about subatomic sized projectiles. Chemical lasers require huge amounts of 'fuel', don't forget.

Both weapons have the problem of beam spread. Which system would spread less over a given distance? Does beam divergence affect weapon performance in the same way for both systems?

Exoatmospheric CPBs would have terrible beam divergence due to repulsion and be influenced by the earth's magnetic field. That's why NPBs were proposed for space weapons, but OTOH they have a little extra beam-spreading when they neutralise the beam. (Endoatmospheric CPBs, however, end up getting neutralised by exchanging electrons with the air anyway, so are better than NPBs for endoatmospheric use).

A PBW can still disable/damage a target even when it's intensity is diminished due to beam divergence, whereas a laser would still need to burn through the armor. Also,

Ancillary kill mechanisms. In addition to the direct kill mechanism of the beam, ancillary kill mechanisms would be available. Within the atmosphere, a secondary cone of radiation symmetrical about the beam, would be created by the beam particles as they collide with the atoms of the air. This cone would be comprised of practically every type of ionizing radiation known (i.e., x-rays, neutrons, alpha and beta particles, and so on). A tertiary effect from the beam would be the generation of an electromagnetic pulse (EMP) by the electric current pulse of the beam. This EMP would be very disruptive to any electronic components of a target. Thus, even if the main beam missed, the radiation cone and accompanying EMP could kill a target. While the EMP and the radiation cone would not be present in an exoatmospheric use of the weapon, there are other possible options in space that are not available in the atmosphere. Many intriguing possibilities come to mind. For example, using lower levels of beam power, the particle beam could expose photographic film in any satellite carrying photographic equipment, or it could damage sensitive electronic components in a satellite.

http://www.airpower.maxwell.af.mil/airc ... berds.html

The suitability of beam weapons really depends on what you want to use them for (eg exo/endoatmospheric) and how theoretical you want to get, about which qualities. IMHO PBWs are superior to lasers, once you ignore cost/feasibility/complexity.

BTW, the Freespace prometheus cannon gave me an idea for an exoatmospheric tunable FEL that fires just the right frequency for maximum interaction (=> energy deposition => damage) with a target's armor (sensors would determine hull composition beforehand).

[18-Till-I-Die]

Question about particel beam firepower:

What exactly, in joules, would be required to vaporize a human being? And, for my limited intelect, just a number please, not with the Es and such as i'm still trying to get that down.

[The Nomad]

At least 200 MJ IIRC. Necronlord or Connor MacLeod did that some time ago...

[18-Till-I-Die]

At least 200 MJ IIRC. Necronlord or Connor MacLeod did that some time ago...

Ah, so anything 200MJ or up would be sufficient? Good, that gives a nice spring board to scale from. Thank you very much

[NecronLord]

At least 200 MJ IIRC. Necronlord or Connor MacLeod did that some time ago...

Yup. Says something nasty about the power generation of those necron rifles that does (Probably almost a gigawatt would be required to make and sustain a beam capable of vaporising - thorough a deliberately inefficient method) a seven foot giant clomping around in super heavy ultra dense powered armour in a fraction of a second. )

A 'plasma beam weapon' might be a proton CPB and electron CPB mixed together for a net neutral charge. Kinda like a Quasi-NPB. I guess technically you could say it's a hydrogen plasma...

So, a plasma weapon that would be relatively unaffected by magnetic fields then? Neat.

[Arrow]

You also have Free Electron Lasers. They could most likely give you the same effects as a heavy element particle cannon with a lower input energy cost. Over course you would probably have to turrent mount the sucker (at those power levels, the beam would destroy a mirror).

Aren't FEL's just the way the LASER beam is generated? I mean they are still LASERS in fucntion? Or are you saying that they get a similar LASER power level as a HEP beam? Just a little unclear on what you are saying is all.

FELs are still lasers, but they use accelecrated electrons passing through a magnetic field to generate the laser beam. FELs should be able to produce very high energy beams that would be able to smash atoms like a particle beam fire netrons or elements (hydrogen, carbon, whatever - basically bigger elements = more damage and more input power). I believe a FEL was used in the late 90's to explode a Xenon atom. This means a FEL beam would probably destroy a mirror. Since electrons are much less massive than neutrons or atoms, the cost for accelerating them is much lower, so a FEL should be a cheaper weapon than a particle beam, in terms of energy.

Hopefully this post is coherent (its too early).

[Shroom Man 777]

Yay! Plasma weapons are feasible! Woohoo! Although I thought they needed some sort of magnetic bottle crap.

[Isolder74]

Question about particel beam firepower:

What exactly, in joules, would be required to vaporize a human being? And, for my limited intelect, just a number please, not with the Es and such as i'm still trying to get that down.

A 10,000 KiloWatt Laser is definately powerful enough. But lasers tend to not vaporise things not in the line of the beam. A steam explosion as the point of beam contact would blow the person apaer at those power levels. The way a laser works would burn through a person before that would happen. The Laser does not normally ever heat anything outside of the beam.

Technically a laser over 1,000 kw is considers by the government as "Weapons Grade" So any laser that powerful and higher is powerful enough to kill.