A ray beam blasts through a steel barrier before being absorbed by the air.
There exist wavelengths far shorter than the visible and near visible part of the spectrum. At TL 11, beams can go into the deep ultraviolet, into parts of the spectum named the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV). This extreme shortwave light can be focused far tighter than near visible light, which increases their range ... in vacuum. In air, or any matter at all denser than a trace gas, the beam is absorbed nearly instantly. Typically emitted as a train of short pulses, these act like a blaster to explode matter they encounter so that subsequent pulses can drill deeper. The ray beam must blast the air out of the way in the same fashion that it blasts solid matter aside. The momentary near vacuum left behind in the center of the air blasts allows the remainder of the beam to pass through. Treat each meter of air as DR 10.
However, there is a benefit to these very short wavelengths - the plasma created by absorption of the beam becomes transparent to the beam. At very tight focus, this allows the beam to travel though the plasma it is creating to drill a deeper hole in materials that are normally too strong to be blasted open. This means that the armor divisor keeps decreasing at shorter and shorter ranges compared to near-visible blasters. At the most intense focus, the intensity of the beam is so high that matter in its way is fully ionized - every chemical bond is broken and the outer electrons are stripped from the atoms. Since non-superscience armors are dependent on chemical bonds for strength and protection, this means that at these extremely tight focuses the beam ignores all DR except for the cover DR due to the interposing object's mass. Find the Armor Divisor for a given fraction of ½D range on the table below
|Fraction of ½D range||Armor Divisor*||Air DR**|
|1||(1)||10 / m|
|0.5||(2)||5 / m|
|0.25||(3)||3 / m|
|0.1||(5)||2 / m|
|0.05||(10)||1 / m|
|0.025||(30)||1 / 3 m|
|0.01||(∞)||1 / 30 m|
* DR after applying armor divisor is never less than the mass-derived cover DR.|
** Multiply by the atmospheric pressure. If not otherwise specified, this can be figured as 30 for Superdense atmosphere, 6 for Very Dense, 1.2 for Dense, 1 for Standard, 2/3 for Thin, 0.25 for Very Thin, and 0 for Trace or vacuum.
Since the rules for losing focus away from the focal point also work in reverse (that is, the beam's effect is treated as longer range as you get closer to the ray guns away from the focal point as fast as when going away from the ray guns from the focal point), this means that deep ultraviolet and soft x-ray wavelengths that go through a large aperture get absorbed almost instantly by the air. To have any reasonable range, ray guns designed for atmospheric use have pinpoint apertures that emit beams which start out thin enough to get the (∞) armor divisor and which are initially propagating parallel rather than converging. One side effect of this is that these beams do not lose focus any faster beyond their target, unlike beams which are focused to a smaller point than their aperture. If you need to use it in vacuum, after-market focal arrays can be attached to the front of the ray gun to allow much longer ranges. All weapons in the default table shown below are assumed to use this option if they are in the deep UV or x-ray region of the spectrum and are not stated to be specifically designed for space combat. To make a custom ray gun designed for atmospheric use simply set the aperture to zero in the form or leave the aperture field blank.
Very little can deflect a beam of these short wavelengths. Since the beam does not necessarily follow the exact same path that the light that can from the target to the gun, the Acc of deep UV and x-ray ray guns is slightly lower than that of visible and near-visible lasers.
The light of these beams is not near-visible. It ignores air and water attenuation, attenuation from atmospheric conditions, will not reflect off mirrors, and cannot propagate through transparent materials without blowing holes in them. The beams will not cause flash-blindness, sunburn, or radiation poisoning - the light from the beams cannot even get though air, much less a human eye or any thickness of human tissue. Consequently, they do not automatically have LC 1 due to these additional hazards to bystanders.
Ray beams are very visible in any kind of atmosphere. They produce a streak of electric blue-hot plasma along the beam path and a thunderclap like a strike of straight lightning. This acts like a tracers for shooting, both showing the gunner the path of the beam and giving away the gunner's position.