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Other tools: Performance Estimation Tool    Magnitude/Flux Density Converter

Spitzer Flux Estimator For Stellar Point Sources
Input: Photometric System
K-band magnitude or, K-band flux density
Spectral Type MK Class
Output: Photometric system zeropoint (Jy) IRAC flux densities (mJy) 15 um flux density (mJy) 24 um flux density (mJy)
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Overview: This tool allows input of a K-band magnitude (CIT, UKIRT or 2MASS systems -- for 2MASS the waveband is actually K-short rather than K) or flux density for stellar point sources. A flux density estimate in the IRAC wavebands and the wavebands of IRS short and long modules, plus the MIPS Si:As 24 micron array is obtained (no color correction is applied). Flux density estimates are based on Kurucz-Lejeune atmospheric models for MK class I, III and V stars (kindly provided by Dr. Sergio Fajardo-Acosta of the Spitzer Science Center).

USE OF THE FLUX DENSITY ESTIMATOR: Use the pull down menus under Photometric System, Spectral Type and MK class to indicate which magnitude system is being used, and the spectral type of the star under consideration. Entry of a magnitude -- under the heading "K-band magnitude" -- provides a conversion to K-band flux density (or enter a flux density to get K-band magnitude), plus an estimate in mJy of the flux density at the four IRAC wavelengths (3.6, 4.5, 5.8 and 8 microns), plus 15 microns (IRS peakup and short wavelength module), and 24 microns (IRS long wavelength module and MIPS Si:As array). K-band flux densities can be entered in a number of units -- use the pull-down menu under "K-band flux density" to find the units you want.

Note: for giant and supergiant stars a more limited set of spectral types are available:

  • Available spectral types for MK class I: O5, O6, O8, B0, B5, A0, A5, F0, F5, G0, G5, K0, K5, M0 and M2.
  • Available spectral types for MK class III: O5, O6, O8, B0, B5, G0, G5, K0, K5 and M0.