Browse Topic: Radiation protection

Items (109)
A versatile, novel, multifunctional hybrid structural composite of a high-hydrogen epoxy matrix (UN-10) coupled with boron and carbon fibers (IM-7) has been developed. Prototype laminates of 18×18 in. (≈46×46 cm), with the nominal areal density of 0.35 g/cm2, were fabricated in this effort. The hydrogen atoms in the epoxy will provide shielding strength against high-energy protons, electrons, and heavy ionic species, while the boron fibers that have a high neutron cross-section will help shield against neutrons and reduce the buildup of high-energy photons from secondary reactions. The carbon fibers will provide improved mechanical strength.
Currently, lead and lead-based materials are used to fabricate shields not only for X-rays, but also for other types of radiation. With the growing environmental concern about the toxicity of lead, and the high costs associated with transporting heavy lead-based shields in spacecraft, alternatives are needed for fabricating X-ray shields that are less toxic and lighter.
The FAA, using its CARI-6 program, provides galactic cosmic radiation dosage rates for any location on the Earth from ground up to 60,000 ft (≈18,300 m). One way to protect astronauts from galactic cosmic radiation (GCR) on a Mars mission is to use material shielding. However, current radiation shielding code does not model shields thicker than about 100 to 200 gm/cm2, and it has been shown that this shield thickness is insufficient to provide protection for a trip to Mars. There is effort underway to extend the code to thicker shields, but there is a lack of experimental data to use to verify the code. The atmosphere represents a very thick and effective radiation shield, and that atmospheric radiation data might be used as a source of verification data.
Items per page:
1 – 50 of 109