Foreground Data

Foregrounds: Diffuse Emission

Data from surveys of diffuse Galactic emission may be obtained from the product table below. Additional pages related to diffuse emission are also available:

  • An Overview of diffuse astrophysical foreground components typically observed at microwave frequencies.
  • Derived maps of emission from individual physical emission mechanisms (e.g., synchrotron, free-free, dust, lines)
  • Software which may be used to model diffuse emission
  • Images of some of the survey and derived products.

Click on Product, Frequency or Release Date to sort by that column.

Product Frequency Release
LWA1 Radio Maps
0.035 GHz to 0.08 GHz 2017 Long Wavelength Array first station maps at nine frequencies from 35 to 80 MHz.
OVRO-LWA Radio Maps
0.036 GHz to 0.073 GHz 2017 Owens Valley Radio Observatory Long Wavelength Array sky maps at eight frequencies from 36.528 to 73.152 MHz.
Haslam 408 MHz
0.408 GHz 2003, 2014 408 MHz radio continuum all-sky map of Haslam et al., and 2014 reprocessed data.
Dickey & Lockman HI Column Density
1.4 GHz 2003 Composite all-sky N(HI) map derived from the Leiden/Dwingeloo survey and supplemented at southern declinations using the compilation of Dickey & Lockman.
LAB HI Survey
1.4 GHz 2005 HEALPIX resampling of Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (from Kalberla et al., 2005).
Effelsberg-Bonn HI Column Density
1.4 GHz 2016 Northern sky N(HI) map from the Effelsberg-Bonn HI survey (Winkel et al. 2016).
HI4PI HI Column Density
1.4 GHz 2016 All-sky N(HI) map constructed from the Effelsberg-Bonn HI Survey and the Galactic All-Sky Survey.
HI4PI High Velocity HI
1.4 GHz 2018 All-sky maps of the column density and velocity of high velocity HI (Westmeier 2018).
1.4 GHz (continuum) 2014 CHIPASS 1.4 GHz Continuum Map
Parkes RRL Survey
Jodrell Bank
1.4 GHz (RRL) 2015 HIPASS Galactic Plane Radio Recombination Line Survey (Alves et al 2015).
Stockert and Villa-Elisa 1.4 GHz Continuum Map
1.4 GHz Continuum 1982, 1986, 2001 This is an all-sky 1420 MHz (21cm) continuum map formed from surveys of the northern sky with the 25-m Stockert telescope and the southern sky with the 30-m Villa-Elisa telescope.
Velocity-Integrated W(CO)(Dame, Hartmann, Thaddeus 2001)
115 GHz 2001 Composite CO brightness temperature map of the Galaxy.
IR (12, 25, 60, 100 um) 2005 IRAS diffuse emission data projected info HEALPix format.
IR (12, 25, 60, 100 um) 2005 Infrared maps from Improved Reprocessing of the IRAS Survey.
IR (65, 90, 140, 160 um) 2015 AKARI far infrared all-sky maps.
Composite all sky H-alpha (Finkbeiner)
optical 2003 Composite all-sky H-alpha map derived from 3 surveys.
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