VizieR Online Data Catalog: HI4PI spectra and column density maps (HI4PI team+, 2016)

The HI4PI data release comprises 21-cm neutral atomic hydrogen data of the Milky Way (-600km/s<vlsr<+600km/s for declination >0°; -470km/s<vlsr<+470km/s for declination <0°) as observed with the 100-m radio telescope at Effelsberg and the 64-m radio telescope at Parkes. HI4PI covers the full 4-pi sky. Spectral data is provided in three forms:

(1) Standard FITS data cubes, for the full sky in both, Equatorial (J2000) and Galactic coordinates, each in four different map projections, AIT, CAR, MOL, and SFL; see world-coordinate-system, WCS, references: Greisen & Calabretta, 2002A&A...395.1061G, Calabretta & Greisen, 2002A&A...395.1077C, Greisen et al., 2006A&A...446..747G

(2) Smaller FITS data cubes, each having a size of about 20x20 sq.deg. For convenience, we provide four different map projections, CAR, SFL, SIN, and TAN (again see WCS references). Note, size in longitude is 20° in absolute coordinates for CAR projection, and 20° true-angular size for SFL, SIN, and TAN projections. Again, Equatorial and Galactic coordinate systems are provided.

(3) FITS binary tables containing lists of spectra sampled on a HealPIX grid (nside=1024, Galactic coordinates, Ring indexing scheme, Gorski et al., 2005ApJ...622..759G). To make handling of the data easier, the table is split into smaller files. Each of these contains spectra belonging to one of the 192 base/parent pixels of the nside=4 pixelization. For convenience, the binary tables also contain EQ2000 and Galactic coordinate positions for each individual spectrum, as well as the associated HealPIX index.

Furthermore, we provide the full-sky HI column density distribution, both, in a (1) HealPIX-grid binary table (nside=1024, Galactic coordinates, Ring indexing scheme), and

(2) Standard FITS 2D images in four map projections, AIT, CAR, MOL, and SFL. Various velocity intervals were applied to calculate NHI. Equatorial and Galactic coordinate systems are provided.

(16 data files).