r-process

chemistry
Also known as: R process, rapid neutron capture, rapid process

Learn about this topic in these articles:

origin of chemical elements

  • geochemical cycle
    In chemical element: Neutron capture

    …be distinguished: the r -process, rapid neutron capture; and the s -process, slow neutron capture. If neutrons are added to a stable nucleus, it is not long before the product nucleus becomes unstable and the neutron is converted into a proton. Outside a nucleus, a neutron decays into a proton…

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stellar nucleosynthesis

  • open cluster NGC 290
    In star: Evolution of high-mass stars

    In this rapid, or r-, process, the evolution of a nucleus can be very different from that in a slow process. In supernova explosions, vast quantities of neutrons can be produced, and these could result in the rapid buildup of massive elements. One interesting feature of the…

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transuranium elements

  • periodic table
    In transuranium element: Synthesis of transuranium elements

    …as rapid-neutron capture, or the r-process (in contrast to the slow-neutron capture, or s-process, described above). Underground detonations of nuclear explosive devices during the late 1960s resulted in the production of significant quantities of einsteinium and fermium isotopes, which were separated from rock debris by mining techniques and chemical processing.…

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