According to one embodiment, a rotating anode X-ray tube includes a cathode, an anode target, a sliding bearing including a rotor, a stationary shaft and a lubricant, and a vacuum tube. The rotor includes a bearing member formed to extend along a rotating axis and positioned to surround the stationary shaft. At least one of the stationary shaft and the bearing member are formed of tungsten carbide, silicon carbide, or titanium carbide.

In an embodiment an X-ray source includes an electron source configured to emit electrons, an acceleration set-up configured to accelerate the emitted electrons and a transmission window downwards of the acceleration set-up, wherein the transmission window is configured to let through X-rays generated by the accelerated electrons, wherein the transmission window is located either in a straight extension of a line-of-flight of the accelerated electrons or off the line-of-flight and past the acceleration set-up, wherein the transmission window comprises a carbon carrier, and wherein the carbon carrier comprises sp2-hybridized carbon.

A system includes a stage for supporting a sample having at least first and second atomic elements. The first atomic element has a first characteristic x-ray line with a first energy and the second atomic element has a second characteristic x-ray line with a second energy, the first and second energies lower than 8 keV and separated from one another by less than 1 keV. The system further includes an x-ray source of x-rays having a third energy between the first and second energies and at least one x-ray optic configured to receive and focus at least some of the x-rays as an x-ray beam to illuminate the sample.

An anode for an X-ray tube is provided to reduce the incidence of off-focus x-ray emissions from the anode. The anode has a rotating component, a body operably connected to the rotating component and adapted to rotate in conjunction with the rotating component, and at least one emissive material track defined on the body wherein the at least one emissive material track has a first width, and wherein the first width is less than or equal to twice a second width of a focal spot track on the body. Further, to enhance the reduction in the off-focus x-ray emission, the emissive material track is formed of a material having a first atomic number and the body is formed of a material having a second atomic number with a ratio of the first atomic number to the second atomic number being at least 6.

In some embodiments, a system may include an X-ray tube assembly having an anode disk assembly. The system may include a motor configured to rotate the anode disk assembly. The system may include one or more pumps configured to draw a vacuum in the X-ray tube assembly. The system may include a cooling system configured to cool the anode disk assembly. In some embodiments, a method may include drawing a vacuum in an X-ray tube assembly with one or more pumps. The method may include rotating an anode disk assembly of the X-ray tube assembly. The method may include cooling the anode disk assembly with a cooling system. The method may include activating a power supply to produce an electron beam. The electron beam may interact with an X-ray generating layer of the anode disk assembly to produce an X-ray beam oriented to impinge on a sample.