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South Pole Telescope (SPT)

Product Name
SPT + Planck maps of the Magellanic Clouds
Mission
SPT

Description

This page provides maps of the Large and Small Magellanic Clouds, produced by combining data from the Planck satellite and the South Pole Telescope. These maps and the method used to create them are described in detail in this paper. Maps are provided in three wavelength bands, centered at roughly 1.4, 2.1, and 3.0 mm. Because the Planck and SPT passbands are not perfectly matched, an assumption has to be made about the true, underlying source spectrum to combine data from the two instruments. Maps are provided in each field (LMC and SMC) and observing band assuming five different underlying source spectra, namely power-law emission I ~ λ (I ~ ν α) with power-law indices α ranging from -1 to 3. For each field and assumed source spectrum, the 1.4 and 2.1 mm maps are provided at three angular resolutions (Gaussian FWHM 1.5, 2.0, and 2.5 arcmin), while the 3.0 mm maps are provided at two angular resolutions (Gaussian FWHM 2.0 and 2.5 arcmin). For each of these 40 maps per field, a null map (that should contain no astrophysical signal but have the same noise properties as the signal map) is also provided.

Maps of the LMC. Filenames are of the form spt_planck_imap_lmc_$BAND$_alpha$ALPHA$_smooth$FWHM$am.fits, where $BAND$ is the wavelength center of the Planck band (1.4, 2.0, or 3.0 mm), $ALPHA$ is the power-law index of the assumed source spectrum (-1, 0, 1, 2, or 3), and $FWHM$ is the FWHM of the Gaussian kernel that sets the resolution of the map (1.5, 1.8, 2.0, or 2.5 arcminutes).

Null maps of the LMC. Filenames are of the form spt_planck_dmap_lmc_$BAND$_alpha$ALPHA$_smooth$FWHM$am.fits, where $BAND$ is the wavelength center of the Planck band (1.4, 2.0, or 3.0 mm), $ALPHA$ is the power-law index of the assumed source spectrum (-1, 0, 1, 2, or 3), and $FWHM$ is the FWHM of the Gaussian kernel that sets the resolution of the map (1.5, 1.8, 2.0, or 2.5 arcminutes).

Maps of the SMC. Filenames are of the form spt_planck_imap_smc_$BAND$_alpha$ALPHA$_smooth$FWHM$am.fits, where $BAND$ is the wavelength center of the Planck band (1.4, 2.0, or 3.0 mm), $ALPHA$ is the power-law index of the assumed source spectrum (-1, 0, 1, 2, or 3), and $FWHM$ is the FWHM of the Gaussian kernel that sets the resolution of the map (1.5, 1.8, 2.0, or 2.5 arcminutes).

Null maps of the SMC. Filenames are of the form spt_planck_dmap_smc_$BAND$_alpha$ALPHA$_smooth$FWHM$am.fits, where $BAND$ is the wavelength center of the Planck band (1.4, 2.0, or 3.0 mm), $ALPHA$ is the power-law index of the assumed source spectrum (-1, 0, 1, 2, or 3), and $FWHM$ is the FWHM of the Gaussian kernel that sets the resolution of the map (1.5, 1.8, 2.0, or 2.5 arcminutes).

A new release of these maps was made available on 12/7/2016, with two very small changes. The zero point of the Planck maps was removed before combining and one keyword was added to the FITS headers. This release also includes maps smoothed to 1.8 arcminute FWHM that were not previously available.

Additional Details:

  • Crawford et al. (2016), "Maps of the Magellanic Clouds from Combined South Pole Telescope and Planck Data", arXiv:1605.00966, ADS.
  • Information on this page was taken from this SPT site.

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Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
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