单词 | r-process |
释义 | > as lemmasr-process r-process n. [ < the initial letter of rapid adj. + process n.] Astronomy a nucleosynthetic process believed to occur in stars in circumstances of high neutron flux (e.g. in supernova explosions), in which atomic nuclei heavier than iron are formed from lighter ones by a succession of rapid neutron captures and slower beta decays. ΘΚΠ the world > the universe > star > star-matter > [noun] > stellar process agglutination1753 nebularizationa1892 fission1919 carbon cycle1940 r-process1956 s-process1956 nucleosynthesis1957 starquake1969 1956 F. Hoyle et al. in Science 5 Oct. 612/2 We have distinguished two conditions under which the Neutron capture can take place, a slow (s) process and a rapid (r) process... The r-process we associate with the explosion of supernovae, the time scale being as small as 10 to 100 seconds. 1977 J. Narlikar Struct. Universe ii. 49 Whereas the s-process produces proton-rich nuclei, the r-process produces neutron-rich nuclei. 2003 Connecting Quarks with Cosmos (U.S. National Res. Council: Div. Engin. & Phys. Sci.) vii. 139 Almost all the relevant r-process nuclei could be accessible for study in a suitably designed two-stage acceleration facility..that produces isotopes and reaccelerates them. < as lemmas |
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