Proton Radiography Essay example -- Nuclear Science

The purpose of this project is to compare radiation imaging simulations of protons to X-rays. In this project proton radiography is proposed as an alternative diagnostic method for the nuclear stockpile. The basis of this project is the use of proton radiography for implosion tests. In any nuclear weapon, implosion geometry is crucial. Implosion tests are needed to ensure that the weapons will perform as expected after years of storage. These tests also help validate computer simulations of nuclear weapon performance. The underground nuclear test ban treaty of 19631 makes confirmation of computer simulations vital to stockpile stewardship. In an implosion test a full-scale weapon mock-up is designed and created using a surrogate metal that has similar mechanical properties to those of the fissile material but cannot produce nuclear reactions. During an implosion, shock waves' high pressures and hot temperatures will cause the solid materials present to flow like liquids. Liquid behav ior can be described by hydrodynamic equations; implosion tests are often called hydro-tests2 in industry. During the Manhattan Project, scientists took snapshots of imploding mock-ups with intense flashes of high-energy x-rays. In 1995 Los Alamos physicist Chris Morris2 developed a way to use protons instead of x-rays for hydro-test radiography. Proton Radiography has many benefits some of which will be discussed in this report. Background Radiography is the production of an image on a radiosensitive surface, such as a photographic film, by radiation other than visible light i.e. radiograph.3 During radiography beams are used to view a material with non-uniform composition. A beam of X-rays is produced by an X-ray generator and is projected towar... ... use of dose cards to compare the dose for each particle to image at various energies. Running the simulation several times with various materials such as Plutonium at compressed densities would also prove more applicable to use for hydro-testing. Works Cited 1. Court, Edward C. Snow and John D. "Radiography Image Detector Capability in MCNP4B." Trans. Am. Nucl Soc. ((1998)): 79, 99. 2. Fishbone, Brian. "shaper X-ray vision for hydrotests." Los Alamos research quarterly . http://www.lanl.gov/quarterly/q_w03/pro_rad.shtml. 3. http://www.state.gov/www/global/arms/treaties/ltbt1.html. "Partial Test Ban Treaty." 1963. 4. Koehler, A.M. "Proton Radiography." Science (1968): 160(3825): p. 303-304. 5. Wolbarst, Anthony B. Looking within: how X-ray, CT, MRI, ultrasound, and other medical images are created . London England: University California Press, 1990.