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Observing Modes - AOTs

A Spitzer Space Telescope observer interfaces with the Observatory and the instruments by means of Astronomical Observation Templates (AOTs). An AOT, one for each of the Spitzer observing modes, permits the user to unambiguously define the parameters of their observing program. The AOT is a central design concept to Spitzer Science Operations. An observation that has been fully defined by supplying parameter values for an AOT is known as an "Astronomical Observation Request" (AOR). Observers use Spot to enter the target information and the observation details into the AOT to create AORs, and ultimately to submit their proposal along with their AORs.

An AOR can be thought of as a list of parameters that (when properly interpreted) describe completely an observation. The completed AORs are deposited into the Spitzer databases. Specially designed software expands each AOR into activities and an uplink sequence for transmission to the spacecraft. It is important to realize that the process of creating commands to carry out an observation based on the AOR parameters is done by software, not by support astronomers at the SSC.

AORs (and related engineering requests) are the basic building blocks for Observatory scheduling. AORs also define unit data sets for pipeline data processing and science archiving.

There is generally no need for observers to modify AORs after submission with the observing proposal (note that Spitzer has a single phase proposal submission process for the most part; see the Current Call for Proposals. Modification of AORs can be made, however, if the observer receives less observing time than requested, or because of changes in Observatory performance.


The Spitzer AOTs:

Warm Mission AOT:

    InfraRed Array Camera (IRAC) Post-Cryo Mapping/Photometry
    The IRACPC AOT is used for simultaneous imaging at 3.6 and 4.5 microns during the Spitzer warm mission, over the two ~5.2 by ~5.2 arcminute fields of view.

Cryogenic Mission AOTs:

    InfraRed Array Camera (IRAC) Mapping/Photometry
    The IRAC AOT is used for simultaneous imaging at 3.6, 4.5, 5.8 and 8.0 microns, over the two ~5.2 by ~5.2 arcminute fields of view.

    InfraRed Spectrograph (IRS) Staring-Mode Spectroscopy
    The IRS staring mode is used for low-resolution long-slit spectroscopy (R= ~60-120) from 5.3 to 40 microns and high-resolution spectroscopy (R=~600) from 10 to 37 microns. It also returns images from the IRS peak-up array, which has a field-of-view of approximately 1 arcminute square and two filters covering 13.5-18.5 microns and 18.5-26 microns. The IRS Staring mode also supports raster mapping.

    InfraRed Spectrograph (IRS) Spectral Mapping
    The IRS Scan AOT is used to perform slit scanning spectroscopy for fields up to a few arcminutes in extent.

    InfraRed Spectrograph (IRS) Peak-Up Imaging (PUI)
    The IRS Peak-Up Imaging (PUI) AOT provides imaging only using the Peak-Up array, which has a field-of-view of approximately 1 arcmin square and two filters covering 13.5-18.5 microns and 18.5-26 microns.

    Multiband Imaging Photometer for Spitzer (MIPS) Photometry and Super-Resolution Imaging
    The MIPS Photometry and Super Resolution AOT is used for imaging photometry and high resolution imaging at 24, 70 and 160 microns.

    Multiband Imaging Photometer for Spitzer (MIPS) Scan Mapping
    The MIPS Scan Map AOT is used for large field maps at 24, 70 and 160 microns. The maps are constructed using slow telescope scanning, combined with motion compensation using a cryogenic scan mirror. Maps are built up of ~5 arcminute wide strips between 0.5 and 6 degrees in length.

    Multiband Imaging Photometer for Spitzer (MIPS) Spectral Energy Distribution (SED)
    The MIPS Spectral Energy Distribution AOT is used for very low resolution (R=15-25) spectroscopy covering 55-95 microns using the MIPS 70 micron Ge:Ga array.

    Multiband Imaging Photometer for Spitzer (MIPS) Total-Power Measurement
    The MIPS Total Power Mode AOT provides zero-level-reference observations for absolute brightness of extended sources.