profitFlux2Mag: Convert between fluxes and magnitudes.

In asgr/ProFit: Fit Projected 2D Profiles to Galaxy Images

Convert between fluxes and magnitudes.

Description

Simple functions to concert between magnitudes and flux given a certain magnitude zero-point.

Usage

profitFlux2Mag(flux = 1, magzero = 0)
profitMag2Flux(mag = 0, magzero = 0)
profitFlux2SB(flux = 1, magzero = 0, pixscale = 1)
profitSB2Flux(SB = 0, magzero = 0, pixscale = 1)

Arguments

flux	Numeric scalar/vector; flux in ADUs given the magzero.
mag	Numeric scalar/vector; magnitude given the magzero.
magzero	Numeric scalar/vector; magnitude zero point. What this implies depends on the magnitude system being used (e.g. AB or Vega).
SB	Numeric scalar/vector; surface brightness in mag/asec^2.
pixscale	Numeric scalar/vector; the pixel scale, where pixscale=asec/pix (e.g. 0.4 for SDSS). If set to 1, then the output is in terms of pixels, otherwise it is in arcseconds.

Details

These functions are here to prevent silly mistakes, but the conversion is almost trivial.

Value

profitFlux2Mag	Returns the magnitude, where mag = -2.5 * log10(flux) + magzero
profitMag2Flux	Returns the flux, where flux = 10^(-0.4 * (mag - magzero))
profitFlux2SB	Returns the surface brightness in mag/sq-asec, where SB = -2.5 * log10(flux) + magzero + 5 * log10(pixscale))
profitSB2Flux	Returns the flux, where flux = 10^(-0.4 * (SB - 5 * log10(pixscale) - magzero))

Author(s)

Aaron Robotham

Examples

profitFlux2Mag(1e5, 30)
profitMag2Flux(17.5, 30)

asgr/ProFit documentation built on Aug. 1, 2024, 8:59 p.m.