format
ll{
values.cosmic.Softcomp: data frame containing cosmic dose rates for shallow depths (< 167 g cm^-2) obtained using the "AGE" program by Rainer Gruen (cf. Gruen 2009). These data essentially reproduce the graph shown in Fig. 1 of Prescott & Hutton (1988).
values.factor.Altitude: data frame containing altitude factors for adjusting geomagnetic field-change factors. Values were read from Fig. 1 in Prescott & Hutton (1994).
values.par.FJH: data frame containing values for parameters F, J and H (read from Fig. 2 in Prescott & Hutton 1994) used in the expression
}
$$Dc = D0*(F+J*exp((altitude/1000)/H))$$source
The following data were carefully read from figures in mentioned sources and used for fitting procedures. The derived expressions are used in the function calc_CosmicDoseRate.
values.cosmic.Softcomp
ll{
Program: "AGE"
Reference: Gruen (2009)
Fit: Polynomials in the form of
}
For depths between 40-167 g cm^-2:
$$y = 2*10^-6*x^2-0.0008*x+0.2535$$
(For depths <40 g="" cm^-2)="" $$y="-6*10^-8*x^3+2*10^-5*x^2-0.0025*x+0.2969$$" values.factor.Altitude
ll{
Reference: Prescott & Hutton (1994)
Page: 499
Figure: 1
Fit: 2-degree polynomial in the form of
}
$$y = -0.026*x^2 + 0.6628*x + 1.0435$$
values.par.FJH
ll{
Reference: Prescott & Hutton (1994)
Page: 500
Figure: 2
Fits: 3-degree polynomials and linear fits
}
F (non-linear part, $\lambda$ < 36.5 deg.):
$$y = -7*10^-7*x^3-8*10^-5*x^2-0.0009*x+0.3988$$
F (linear part, $\lambda$ > 36.5 deg.):
$$y = -0.0001*x + 0.2347$$
J (non-linear part, $\lambda$ < 34 deg.):
$$y = 5*10^-6*x^3-5*10^-5*x^2+0.0026*x+0.5177$$
J (linear part, $\lambda$ > 34 deg.):
$$y = 0.0005*x + 0.7388$$
H (non-linear part, $\lambda$ < 36 deg.):
$$y = -3*10^-6*x^3-5*10^-5*x^2-0.0031*x+4.398$$
H (linear part, $\lambda$ > 36 deg.):
$$y = 0.0002*x + 4.0914$$Version
0.1