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21Ne*

The source of the neutrons for the s process is (a, n) reactions on n-rich nuclei such as 13C or 21Ne, with the latter being most important. In population II and I stars, one can get side reactions such as ... [Pg.351]

Libarkin JC, Quade J, Chase CG, Poths J, McIntosh W (2002) Measurement of ancient cosmogenic 21Ne in quartz from the 28 Ma Fish Canyon Tuff, CO. Chem Geol 186 199-213 Lide DR (ed) (1999) CRC Handbook of Chemistry and Physics (79th edition). CRC Press, Boca Raton, p 14-lb-14-22... [Pg.278]

In fig. 2a-f the results are given for isoscalar and isovector transition amplitudes for 21Ne(T> i, Tz i). (The values of the isovector amplitudes have been multiplied by a factor /3, compared to the conventional definition [BRU77] )... [Pg.126]

Sample/References 3He (10 9cm3g ) 3He/4He (10 4) 20Ne (10-9cmV) e/22 21Ne/22Ne... [Pg.134]

Production rate atomsg 1 (target) a-1. All data are at sea level and at higher latitudes (>60°). Data are from Lai (1991) and ( ) are from Niedermann et al. (1994). Numerals in parentheses are neon production rate ratios normalized to 21Ne in Si for the main target elements (Schafer et al., 1999). [Pg.142]

After the production rates for the cosmogenic 3He and 21Ne are accurately known, they can be used to date the exposure age of surface rocks to cosmic ray radiation. With the use of these cosmogenic nuclides, a few attempts have been made to determine the exposure age of surface rocks (e.g., Kurz, 1986 Staudacher Allegre, 1991 Cerling, Poreda Rathburn, 1994 Wells et al., 1995). However, the ages thus determined have considerable uncertainty. This is because in addition to the uncertainty... [Pg.145]

Hunemohor (1989) obtained an empirical relationship between the nucle-ogenic isotopic ratio (21Ne/22Ne)nud and an O/F ratio from measurements of U-rich minerals ... [Pg.150]

In Table 5.7, we compiled production ratios of (21Ne/4He)nuci and (22Ne/4He)nild isotopes observed in various crustal samples. The water and gas samples cover a wide range of sampling sites and give fairly consistent ratios, being in harmony with the foregoing assumption of a well-defined crustal He and crustal Ne. ... [Pg.151]

Sample (21Ne/4He)nucl (xltT8) (22Ne/4He)nucl (xlO 6) pNe/ eW, References... [Pg.152]

See other pages where 21Ne* is mentioned: [Pg.43]    [Pg.1047]    [Pg.140]    [Pg.206]    [Pg.97]    [Pg.341]    [Pg.341]    [Pg.342]    [Pg.377]    [Pg.293]    [Pg.95]    [Pg.351]    [Pg.54]    [Pg.99]    [Pg.723]    [Pg.12]    [Pg.23]    [Pg.23]    [Pg.24]    [Pg.24]    [Pg.79]    [Pg.90]    [Pg.92]    [Pg.141]    [Pg.142]    [Pg.144]    [Pg.144]    [Pg.145]    [Pg.146]    [Pg.149]    [Pg.149]    [Pg.150]    [Pg.150]    [Pg.150]    [Pg.151]    [Pg.152]    [Pg.152]    [Pg.152]    [Pg.153]    [Pg.153]    [Pg.154]    [Pg.168]   
See also in sourсe #XX -- [ Pg.145 ]



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