astrolibR (version 0.1)

planck: Calculate the Planck function in units of ergs/cm2/s/A

Description

Calculate the Planck function in units of ergs/cm2/s/A

Usage

planck (wave,temp)

Arguments

wave

wavelength(s) at which the Planck function is to be evaluated, in Angstroms, scalar or vectxor

temp

temperature of the Planck function, in degree K, scalar

Value

bbflux

blackbody flux (i.e. pi*Intensity) at the specified wavelengths, in erg/cm^2/s/A

Details

In this function, the wavelength data are converted to centimeters, and the Planck function is calculated for each wavelength point. See Allen (1973, sec 44) for more information. If a star with a blackbody spectrum has a radius R and distance d, then the flux at Earth in erg/cm^2/s/A will be bbflux*R^2/d^2.

References

Allen, C. W., "Astrophysical Quantities", Athlone Press, 3rd ed. http://adsabs.harvard.edu/abs/1973asqu.book.....A

Examples

#   Calculate the blackbody flux at 30,000 K every 100 Angstroms between 2000A and 4000A

wave = 2000 + seq(0,2000,by=100)
plot(wave, planck(wave,30000), lty=1, lwd=2)