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Other tools: Performance Estimation Tool    Magnitude/Flux Density Converter

Overview: A Spectroscopy "Performance Estimation Tool" (SPEC-PET). For user configured Spitzer/IRS observing parameters, the SPEC-PET returns an estimate of the instrument sensitivity and an estimate of the signal-to-noise for user supplied source continuum flux density, wavelength. For MIPS SED mode, sensitivities are returned at 60, 75 and 90 microns.

Input: choose IRS module, ramp duration, number of cycles, and wavelength for sensitivity output. Configure MIPS SED exposure time and number of cycles.

Output: sensitivity and signal-to-noise for the selected observing mode and wavelength, and user specified source parameters.

Help: see the SPEC-PET help page.

Warning: For each cycle of the IRS Staring mode AOT, two exposures are obtained. The sensitivity quoted here assumes that both exposures have been combined, and that the sensitivity of the combined image has scaled as 1/sqrt(2) times the sensitivity of the individual images. Similarly, for multiple cycles, the sensitivity quoted assumes that the sensitivity of the combined image has scaled as the 1/(square root of the number of cycles). n.b. The sensitivities given in the SOM (section are for a single exposure.


Background level:   

IRS Observing parameters:
Mode: Ramp duration
Number of cycles Point source flux density at fiducial wavelength (mJy) Wavelength
   SH: Hi Res 10.0 - 19.5 microns
   LH: Hi Res 19.3 - 36.9 microns
   SL2: Low Res 5.2 - 8.7 microns
   SL1: Low Res 7.4 - 14.0 microns
   LL2: Low Res 14.0 - 21.3 microns
   LL1: Low Res 19.5 - 38.0 microns

MIPS SED Observing parameters:
Exposure time:    Number of cycles:


Help: see the SPEC-PET help page.