Point Source Sensitivity for MIPS
Photometry and Super Resolution AOT:
Large Field Option
Go to the "Small Field" Sensitivity
Estimates
The following charts give the anticipated MIPS point source sensitivity
in the photometry and super resolution observing mode. Separate charts are
given for each of the three wavelength bands and the available pixel
scales and dither options. The individual points are located at the
effective integration times for 1, 2, 3, 4, .... cycles of the dither
pattern. Super resolution measurements at 70 microns must be made with the
fine pixel scale (4.9"/pixel). Full sampling of the point spread function
at 24 and 160 microns is accomplished through the standard dither
patterns.
Each exposure cycle provides multiple exposures resulting in a minimum
integration time that is longer than the selected single frame exposure
time. These multiple exposure integration times are reflected in the
quantized points on the sensitivity charts.
Tthe Spitzer Observer's Manual summarizes the frames per
observation cycle and the integration time per pixel for the various
photometry and super resolution modes.
Background point source confusion is a function of the location on the
sky. The confusion limits shown should be considered optimistic lower
limits. See note on confusion limits here.
The "large field" option is intended for sources too spatially extended to
obtain background measurements within the array fields of view. We show
here the sensitivities for the large field option only.
The large field will produce the same sensitivities for equivalent
on-source integration times as the small field option. Exact large field
sensitivities will depend on how the background is subtracted and measured
from the data. The sensitivities given here are for on-source
data only, with no background subtraction assumed. A factor 1.4 should be
multiplied to the on-source integration time to account for a simple
arithmetic background subtraction.
Go to the "Small Field" Sensitivity
Estimates
Large Field Option Sensitivities:
See note on confusion limits here.
- Low Background:
- 24 micron
70 micron (default scale)
70 micron (fine scale)
160 micron
- Medium Background:
- 24 micron
70 micron (default scale)
70 micron (fine scale)
160 micron
- High Background:
- 24 micron (note that 30
seconds is too long an exposure for the high-background case)
70 micron (default scale)
70 micron (fine scale)
160 micron
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