Emittance: the inherent dispersion of a particle beam. Equivalent to temperature.
Electrostatic Bloom: a very rapid widening of a particle beam that de-focuses it and spreads its energy rapidly.
Pinch: the compression of an electrically conducting filament by magnetic forces. The conductor is usually a plasma, but could also be a solid or liquid metal. Pinches occur naturally in electrical discharges such as lightning bolts, planetary aurora, current sheets, and solar flares. Artificial pinches are used in particle beams, fusion or conversion reactors and drives, solar plasma mining, and magnetic ramscoops and braking systems.
Particle beam weapons fire a rapidly pulsed stream of relativistic or ultra-relativistic subatomic particles or atoms (known as bunches), causing damage both through direct heating and severe radiation exposure. Particle beams can pose a radiation hazard to all bionts and non-radiation hardened electronics in the vicinity of the beam's point of incidence and, in atmosphere, near the path of the beam itself.
Modern ship-mounted particle beam weapons can fire and retarget as fast as 1000 times per second, and have effective ranges up to several light-seconds, depending on the target. Energy to target ranges from tens of gigajoules to multiple terajoules, equivalent to the detonation of several tons to a kiloton or more of conventional explosive per shot.
Habitat or other 'fixed' installations (or the occasional notably large ship mounted unit) may exceed the performance of common ship-mounted weapons by anything up to several orders of magnitude.
Categories of Particle Beam
In the vacuum of space, highly charged electrons repel each other and low energy beams quickly lose focus. In addition, the electrons are deflected by planetary magnetic fields and the magnetic fields in the solar wind, causing their paths to veer erratically. However, a variety of mechanisms are available to compensate for this.
Using a combination of careful bunch design to maximize charge and rapid acceleration of the bunches up to ultra-relativistic velocity, extremely high energy beams carrying powerful currents can be produced. The high currents and overall particle energies cause the beam to self-pinch, reducing emittance by a factor of 1/gamma and electrostatic bloom by N/gamma^2 with N being the number of particles in each bunch. The combined effect results in particle beams able to deliver up to multi-Terawatt energies over ranges of several light-seconds for fixed targets, or up to a light-second for ship-to-ship combat (due to the combination of light-speed lag and vessel maneuverability).
When firing electron beam weapons, an artificial magnetosphere or similar system is deployed to neutralize the ship or beam installation and avoid distortion of the beams or the creation of damaging short circuits.
Electron beams are also used when radiation weapons are needed in an atmosphere. Even a modest particle beam weapon can easily penetrate the entire thickness of a terrestrial planetary atmosphere with minimal interference, although gas giant atmospheres can be more challenging. The high currents again cause the beam to self-pinch, reducing beam spread due to scattering off air molecules. When firing through a terrestrial class atmosphere, the only real limit on the range of the beam is the horizon or major geological features such as mountain ranges that cannot be readily shot through.
An electron beam in air looks like a geometrically straight bolt of blue-white lightning, surrounded by a blue nimbus of Cerenkov radiation due to the electrons scattered from the primary beam. Scattered electrons and bremsstrahlung x-rays create a high radiation environment both near the beam path and in the vicinity of the point of incidence of the beam.
Electron accelerators are typically long, linear structures ranging from 1-1000 meters in length, although both larger and smaller units are not uncommon, particularly ultratech or transapientech devices constructed with magmatter components or built for specialized environments or applications.
Electron beams are easily steered with magnets. This enables the beam to be rapidly redirected without turning the entire accelerator.
Proton beams are also used for combat in vacuum or atmosphere. Individual protons are accelerated to ultra-relativistic velocities. As the beam exits the accelerator, it is neutralized by injecting an electron beam to cancel the charges. This prevents de-focusing via self-repulsion and keeps the beam from veering in ambient magnetic fields.
The primary limit to the range of a proton beam is the thermal velocity of the protons. Neutralization unavoidably heats the beam due to the energy of recombination with the electrons. After exiting the accelerator, they begin to drift apart at roughly 15 km/s. The higher the proton energy, the farther the travel in the time it takes the beam to disperse.
Weapons class proton beam accelerators are typically circular tracks tens of meters to several tens of kilometers in diameter. Due to the size of the storage rings and the cycling time between ready charged shots, proton beams are generally preferred for larger defensive installations, where the system's capacity to store accelerated packets for long periods of time provides a series of rapid-fire high-energy particle beams ready for rapid release on demand.
Like electron beams, proton beams can be steered with magnets prior to neutralization. In addition, the beam can be emitted from several ports along the ring diameter, allowing rapid retargeting.
The relativistic protons in these beams can be extremely penetrating, typically punching through a meter or so of solid or liquid matter before disintegrating into a shower of radiation, which itself can penetrate many more meters of solid or liquid matter. These "cascade" radiation showers produce an extremely high radiation environment which will sterilize the area of all biological life and destroy unhardened electronics. The only defense against a proton beam is thick layers of inert shielding, or using only radiation hardened control systems. Proton rich shielding is most effective on a per-mass basis.
In an atmosphere, proton beams are at least as effective as electron beams, or even more so depending on local conditions and proper adjustment of the beam.
Occasionally ion beams may be used instead of proton beams. Ions are more difficult to accelerate and collimate into beams than protons, but their greater mass makes them more resistant to emittance when neutralized.
Neutron and Muon Beams
Weapons grade neutron beams can pass through several tens of centimeters of solid matter with little interaction, but will rapidly interact with any material containing hydrogen (including water, wax, oil, and biological tissue). The interaction process heats the hydrogenated material in the beam path, to the point of boiling or even exploding it. A neutron beam will also cause residual radioactivity where it strikes heavy elements.
While modosophont technology has been able to generate high energy neutron beams since the early First Federation period, the difficulty of focusing them much beyond the level of creating a 'neutron spotlight' limits their application to ranges of a few tens of kilometers. Over the 1-3 light-second ranges that much of space combat entails, proton or electron beams provide superior range and performance and are much easier to generate.
Muons are short lived particles when at rest but may be an effective particle weapon medium when accelerated up to relativistic or ultra-relativistic velocities. However, muons cannot be stored, are comparatively difficult to produce, and must be made in the moment they are used, generally limiting their utility as weapons.
There are occasional reports that transapient intelligences have used neutron and muon beams in conflicts and that these weapons demonstrate a range and power far beyond that achieved by modosophont technology. Ranges of tens of thousands of kilometers all the way to multiple light-seconds have been described, apparently dependent on the S-level of the creating intelligence. How this is done remains a subject of speculation and rumor. It has been theorized that at the First and Second Singularity level some variant of quantum levitation technology may be in use and that at the Third Singularity and above magmatter - with its ability to host enormous magnetic fields - plays a key role. Inquires directed toward even the most forthcoming transapients or archailectavatars are either ignored or answered with contradictory or even incomprehensible explanations.
The production and storage of antimatter on an industrial scale has been a routine process since before the Technocalypse. Amat based weapons, such as ACER rounds and antimatter flechettes are ancient weapons that continue to see use to this day. Antimatter particle beams have also been a part of various arsenals down through the ages and into the Current Era. However, their use is not as widespread as one might initially think. This is primarily due to the trade-off between the increased damage that a beam of anti-particles can inflict on a target compared to an otherwise identical conventional matter beam and the increased damage that a ship or installation mounting such weapons may suffer if antimatter containment is lost, whether by accident or enemy action. This issue, as well as the added effort required to manufacture and transport antimatter to wherever a given weapon may be (a constantly moving target when ship mounted weapons are considered), often leads to the conclusion that the necessary resources can be better used on creating a more powerful proton or electron beam weapon instead.
Concerns about antimatter generation and containment cease to be a factor beginning at the Third Singularity when the use of Q-mirror technology allows virtually lossless conversion of matter to antimatter within the particle cannon as it is fired. As a result, the use of antimatter beam cannon increases exponentially, often being the standard beam type deployed unless exotic particle weapons are available.
Exotic Particle Beams
Beyond beams of matter or antimatter are the exotic particle beams. Often more rumored than observed, these are weapons that make use of effects at or beyond the limits of modosophont understanding.
Monopole Beams - The most basic of the exotic particle technologies, and the only one even remotely accessible to modosophonts. Monopole beams alternate beams of magnetic monopoles with more conventional particle beams. The plasma created by the conventional particle strikes is then catalyzed by interactions with the monopoles, releasing more energy than would otherwise be produced by a conventional matter beam alone.
The large mass of a magnetic monopole make monopole beams more difficult to accelerate, although this is mitigated significantly by the ease with which they can be manipulated using magnetic fields. Monopole beam weapons may also be limited by the need to mass produce and store monopoles, although larger installations may simply incorporate production and storage units into their on-site support structure.
The best modosophont beams use careful bunch design to maximize the odds of creating the most energetic reaction possible at the target. Transapient systems go even further, apparently using some form of reactive feedback or predictive utility to continuously modify their bunch design in real time - maximizing matter to energy conversion reactions from moment to moment as the target is disrupted by the detonation of earlier bunches.
Monopole beams are one of the few weapons accessible to modosophonts and low transapients that have even a slight effect on magmatter.
Q-Beams - Operating far beyond the level of modosophont or low transapient conflict, Q-beams are said to be based on bunches built of Q-balls. The actual mechanism for accelerating Q-balls to effective particle beam velocities is unknown, although it has been speculated that some form of void bubble - perhaps a specialized form of halo technology - may be involved.
As the Q-balls pass through the target, they convert any matter they encounter into anti-matter, creating an ongoing explosive reaction that can continue long after the Q-beam weapon itself has ceased firing. In principle, such reactions can continue as long as there is matter left to react at the target. In practice, the resulting detonations tend to rapidly remove any extant matter from the area in short order (as a form of exotic dark matter, Q-balls are not subject to the effects of conventional matter explosions).
Depleted Q-Beams - Even more fearsome than a Q-beam, a Depleted Q-beam (usually abbreviated to dQ-Beam) fires bunches of depleted (or more commonly partially depleted) Q-balls at the target and then somehow arranges for the Q-balls to release their entire accumulation of vacuum stored mass-energy in a single powerful detonation. While the vast majority of dQ-Beam particles contain only a miniscule fraction of their full potential - the equivalent of only a few kilograms to a few metric tons of stored energy - due to E=mc2 this is sufficient to result in multiple megatons per second (at least!) being released at the point of beam impact.
Smart Weapons - Text by M. Alan Kazlev, from Anders Sandberg's Big Ideas Grand Vision Weapons with have varying amounts of intelligence in them (rarely more than turingrade). The simplest Smart Weapons link to a control-command subturing and give the owner the ability to shift between types of ammo, see through the aimpoint camera etc. This kind of connection is necessary for use in teamware, and is practically standard among even the simplest baselines. The scramjet bullets of the sabot pistols of Trillicon have built in cameras and some limited steering capabilities. Zetatech's Marksman Gun is equipped with a n expert system that can act as a point defence or drone if placed on a tripod or suitable vehicle (although the price tag deters most people).