User:Rickert/Sandbox

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1 formulae
2 See also
3 Examples of carbon dating and historical disputes
4 References
5 External links
6 Note: Computations of ages and dates

[edit] formulae

${}^1\!X$

$\frac{d{}^{40}\!K}{dt} = -\lambda {}^{40}\!K.$

[edit] See also

Articles on

[edit] Examples of carbon dating and historical disputes

The method and its results are rejected by creation science and Young Earth creationism for religious reasons.

[edit] References

NOAA [1]
Gerhard Morgenroth: "Radiokarbon-Datierung: Xerxes' falsche Tochter", Physik in unserer Zeit 34 (1), S. 40 - 43 (2003), ISSN 0031-9252 Abstract
Definitions and use of the radioactive decay constant and other constants characterizing radioactive decay
Discussion of half-life and average-life in measurements of radioactive decay
Radiocarbon - The main international journal of record for research articles and date lists relevant to 14C
Harry E. Gove: From Hiroshima to the Iceman. The Development and Applications of Accelerator Mass Spectrometry. Bristol: Institute of Physics Publishing, 1999
Roman Laussermayer: Meta-Physik der Radiokarbon-Datierung des Turiner Grabtuches. VWF Verlag für Wissenschaft und Forschung, Berlin, 2000, ISBN 3-89700-263-9.
J. R. Arnold and W. F. Libby, Age Determinations by Radiocarbon Content: Checks with Samples of Known Age (Science (1949), Vol. 110)
Michael Friedrich, Sabine Remmele, Bernd Kromer, Jutta Hofmann, Marco Spurk, Klaus Felix Kaiser, Christian Orcel, Manfred Küppers: The 12,460-Year Hohenheim Oak and Pine Tree-Ring Chronology from Central Europe—a Unique Annual Record for Radiocarbon Calibration and Paleoenvironment Reconstructions. Radiocarbon 46/3, S. 1111-1122 (2004).
Libby, W. F., Radiocarbon Dating, 2nd ed. (Univ. of Chicago Press, Chicago, Ill.,. 175 pp., 1955).
Radiocarbon dating in Cambridge: some personal recollections. A Worm's Eye View of the Early Days, by E. H. Willis [2]
de Vries, Hessel (1916-1959), by J. J. M. Engels [3]
The Discovery of Global Warming, by Spencer Weart [4]

[edit] External links

[edit] Note: Computations of ages and dates

The radioactive decay of carbon-14 follows an exponential decay. A quantity is said to be subject to exponential decay if it decreases at a rate proportional to its value. Symbolically, this can be expressed as the following differential equation, where N is the quantity and λ is a positive number called the decay constant:

$\frac{d<sup>40</sup>Ar}{dt} = -\lambda N.$

The solution to this equation is:

$N = Ce^{-\lambda t} \,$ ,

where $C$ is the initial value of $N$ .

For the particular case of radiocarbon decay, this equation is written:

$N = N_0e^{-\lambda t}\,$ ,

where, for a given sample of carbonaceous matter:

N 0

= number of radiocarbon atoms at

t = 0

, i.e. the origin of the disintegration time,

N

= number of radiocarbon atoms remaining after radioactive decay during the time

t

λ =

radiocarbon decay or disintegration constant.

Two related times can be defined:

half-life: time lapsed for half the number of radiocarbon atoms in a given sample, to decay,
mean- or average-life: mean or average time each radiocarbon atom spends in a given sample until it decays.

It can be shown that:

t 1 / 2

= $\frac{\ln 2}{\lambda}$ = radiocarbon half-life = 5568 years (Libby value)

t a v g

= $\frac{1}{\lambda}$ = radiocarbon mean- or average-life = 8033 years (Libby value)

Notice that dates are customarily given in years BP which implies t(BP) = -t because the time arrow for dates runs in reverse direction from the time arrow for the corresponding ages. From these considerations and the above equation, it results:

For a raw radiocarbon date:

$t(BP) = \frac{1}{\lambda} {\ln \frac{N}{N_0}}$