X pinch X-ray radiation above 8 keV for application to high-resolution radiography of biological specimens

Abstract

The X pinch is a dense plasma X-ray source that is known to emit subnanosecond bursts of X-rays in the 2.5-8 keV energy range from a very small ( 1 m) source commonly referred to as a micropinch. As such, it has been successfully used as a point source for X-ray radiographic imaging of small biological samples with spatial resolution as good as 1-2 m. Recent experiments show that the soft X-ray emission from a micropinch extends out to as high as 15 keV, and that there is also harder radiation from a slightly displaced 100 m source with photon energies reaching above 60 keV that appears to be due to the presence of several-nanosecond electron-beam pulse. Both of these harder X-ray sources are potentially useful X-ray sources for high-resolution radiography of thicker biological samples than we have previously imaged. A characterization of these two hard X-ray radiation sources from X pinch plasmas using a slit camera with different filters, as well as imaging of a variety of biological objects on each pulse, revealed the energy range and source size of the micropinch radiation separate from the larger electron-beam source. High-resolution images (1-10 m scale resolution) of samples, such as a boron fiber with tungsten core (2.5-12 keV) as well as a several-millimeter-thick chicken wing with bone ( 10 keV), will be presented.Index Terms-Biomedical application of X-rays, plasma pinch, X-rays, X-ray imaging, X-ray source.

X-Pinches as Broadband Sources of X-Rays for Radiography

“…It is one of the brightest soft X-ray sources emitting in the photon energy range of 1 -10 keV, and it possesses unique parameters: a micron (µm)-size radiating region and a picosecond time scale pulse duration [4]- [7] [8]. Such a radiation source is ideal for the method of point-projection X-ray imaging, which is an efficient diagnostic means to obtain both qualitative and quantitative data on the object under study [21].…”

Mo x-pinch performance from a new compact and portable 1-kA/ns 2-LTD-Brick driver

“…The fact that one or more radiation spots are always formed in a predictable location (within the 100-200 μm z-pinch plasma column), in predictable times (with 2-ns jitter), along with its unique x-ray characteristics, make x pinches a better choice in many applications in plasma physics, biology and others, which we briefly referenced in Table 1.2-3. Radiography of wire array z pinches [2] [21] [22] Phase-contrast imaging of soft biological objects [13] [23] [24] [25] Study of CH foams inside wire array z pinches [26] Study of inertial-confinement-fusion capsule shells [27] We summarize some known pulsed-power, high-current x-pinch generators in the "Marx (technology)" in the table above assumes that pulsed-power generators are based on one or more oil-insulated Marx generators, pulse-forming and transmission lines to compress and deliver pulses to x-pinch load, and gas switches. All such pulsed-power systems are able to deliver a large, fast-rising current to a low-inductance, x-pinch load and have, for decades, generated a huge amount of x-pinch research around the world.…”

“…kV with about -11-kV reversal at the load. The lower load voltage allows us to minimize the unwanted bremsstrahlung radiation from e-beam [25], which follows very shortly after…”

Resolving microstructures in Z pinches with intensity interferometry

“…2,3 Small intensely radiating spots within X pinches have been applied to produce high-resolution radiography. 4 For a detailed exposition and summary of these features applied to X pinches, see, e.g., Ref. 5.…”