SINGS: Summary Page Information
Most of the text below is taken directly from the SINGS delivery document; please use that document for a full understanding of the SINGS Enhanced Products data. The information below is a short summary of the naming convensions used in the SINGS Summary Pages.Ancillary Data
The image (FITS) ancillary data available for download are listed based on filter/band of the observation, which is stripped out of the file name of that dataset [ngcXXXX_#_dr4.fits (with #=B,V,R,I,Ha,Ha_SUB,R_short; e.g., ngc5194_Ha_dr4.fits)]. For each image a link to the FITS version is listed first, followed by a link to the JPEG preview (created by IRSA using the the Montage software tool suite.)
On the lefthand side, a 3-color image has been created for preview purposes by IRSA, also using Montage [B (blue) + R (green) + I (red)]. This image can be seen in full resolution by clicking on the small thumbnail on the Summary page. Note, in some cases R band images were not available, so V band was used instead of R in the 3-color image. When three optical bands were not available, the 3-color image preview was not created.
Optical images (B,V,R,I,Ha) are available for 73 galaxies (62 in Ha); galaxies missing any type of optical images are: NGC0855 and NGC4569; for NGC5055 and NGC5408 only Ha images are available; these data are not being re-delivered in DR5, as DR4 was their last delivery.
The images are either single pointings, or mosaics of 2 or more adjacent and partially-overlapping frames. The images are not background-subtracted. All optical data are single extension FITS files (one file for each filter); they are flux calibrated and have astrometric solutions. Photometric and astrometric keywords are stored in the FITS headers.
The pixel scale is 0.305 arcsec (KPNO data) or 0.433 arcsec (CTIO data). The images have NE orientation, and are registered to a common frame. The flux scale is count/sec (CPS), and the relevant photometric keywords are: PHOTFLAM, to convert CPS to Jy, and ZPOINT, for the zeropoint.
Optical Spectra
One-dimensional (1D) spectra in the wavelength range 0.36-0.70 µm are delivered for 66 of the 75 galaxies. For most galaxies, two spectra are delivered: the nuclear spectrum, and the central 20 x20 drift-scan spectrum. These ascii text spectra ancillary data available for download are listed based on type of spectum, which is stripped out of the file name of that dataset [ngcXXXX_nuclear_002_5.txt and ngcXXXX_drift_020_020.txt are called "NUCLEAR and "DRIFT" in the listings]. For each spectrum a link to the ascii text version is listed first, followed by a link to the JPEG preview (created by IRSA using the the unix "graph" tool.)
The nuclear spectra are 2.5 x2.5 (KPNO) or 2.5 x3.0 (CTIO) aperture extractions of the brightest few central pixels. The 20 x20 drift-scan spectra target the central region of each galaxy, in a similar fashion to some of the IRS spectra. Both type of optical spectra are wavelength and flux calibrated. Resolution is ~8 Angstrom, and all fluxes are corrected for foreground Galactic extinction.
- Nuclear spectra: a 2".5 wide aperture (3" at CTIO) was pointed at the brightest central spot of the galaxy;
- 20" drift scans: the slit was drifted for 20" around the central region, while exposing;
- 55" drift scans: similar to the 20" drift scans, with a scan length of 55".
Optical spectra are available for 66 SINGS galaxies. Galaxies missing optical spectroscopy are: HoII, NGC3034, NGC4236, NGC4631, DDO154, NGC5408, IC4710, NGC6822, NGC7552. These data are not being re-delivered in DR5, as DR4 was their last delivery.
A link is also available to search the NASA/IPAC Extragalactic Database (NED) using the name of the SINGS object. Lastly, the IRSA Archive search link uses IRSA's inventory service (RADAR) to check for other data in the archive matching the SINGS galaxy name/position.
IRAC Data
The image (FITS) IRAC data available for download for all 75 SINGS galaxies, and are listed in order of the channel number of the observation [IRAC Channel 1 = IRAC1; IRAC Channel 2 = IRAC2; etc]. For each image a link to the FITS version is listed first, followed by a link to the JPEG preview (created by IRSA using the the Montage software tool suite.) The weight maps (_wt.fits) images are also listed per IRAC channel number, along with a JPG preview, made by IRSA.
On the lefthand side, an IRAC 3-color image has been created for preview purposes by IRSA, also using Montage [ch1 (blue) + ch2 (green) + ch4 (red)]. The center section/panel is displayed on the Summary page; this image can be seen in full resolution by clicking on the small thumbnail on the Summary page.
For each galaxy, 4 mosaics, along with 4 weight maps, one for each of the four IRAC bands, are delivered as single-extension FITS files. The pixel scale of the mosaics is 0.75 arcsec, and the flux scale is MJy sr-1.
MIPS Data
The image (FITS) MIPS data available for download for all 75 SINGS galaxies, and are listed based on bands of the observation [MIPS24, MIPS70 and MIPS160]. For each image a link to the FITS version is listed first, followed by a link to the JPEG preview (created by IRSA using the the Montage software tool suite.) For each of the MIPS bands, the entire/large image is listed first per band, followed by a "crop"/smaller image version of just the center area around the galaxy in that band.
On the lefthand side, a grayscale image of the MIPS24 "crop" image has been created for preview purposes by IRSA, also using Montage. This image can be seen in full resolution by clicking on the small thumbnail on the Summary page.
For each galaxy, 3 mosaics, one for each of the MIPS bands, are delivered as single-extension FITS files. The pixel scale of the MIPS mosaics is wavelength-dependent: 0.75 arcsec at 24 mm, 3.00 arcsec at 70 mm, and 6.00 arcsec at 160 mm. The flux scale is MJy sr-1.
DR5 contains MIPS-SED data cubes and 1D extractions for 56 SINGS galaxies. Cube FITS images, uncertainty maps, 1D extractions and Previews are available for download. Previews of images are created by IRSA using Montage. Previews of the SED 1D spectra are created by IRSA using the unix "graph" program; error bars have been included in the plot Preview
IRS Data
For 70 galaxies (all those with IRS data), six 2-dimensional maps of the nuclear region (maps of poly-cyclic aromatic hydrocarbon emission at 7.6um+8.6um and 11.3um, continuum-subtracted maps of [Ne III] and [Si II], and complementary continuum maps at 15um and 35um) are delivered. One-dimensional spectra for each nuclear region in all four IRS modules are also delivered (Short-Low (SL) >5-15 um; Long-Low (LL) >15-37um; Short-High (SH) >10-20um; and Long-High (LH) >20- 37um), ranging in size from 22.63×14.83 (high resolution, SH and LH) to 503×333 (low resolution, SL and LL). One-dimensional spectra are in ASCII (*.tbl), while the maps are in FITS format.
The IRS image (FITS) data available for download are listed based on line maps of the observation [neIII, siII, pah_8, pah_11_3]. For each image a link to the FITS version is listed first, followed by a link to the JPEG preview (created by IRSA using the the Montage software tool suite.) Note, the IRS FITS images are very small and therefore the JPEG previews are tiny and difficult to view in their original scale; to aid with visualization the previews have been enlarged and smoothed.
IRS 2D Maps: ngcXXXX_DR5_MD#_line.fits (line=neIII, siII, pah_8, pah_11_3), continuum ngcXXXX_DR5_MD#_line_cont.fits and uncertainties ngcXXXX_DR5_MD#_line_cont_unc.fits.
The IRS spectra data cubes (FITS) are listed next, along with Preview file links. Note, the IRS FITS image cubes are very small and therefore the JPEG previews are tiny and difficult to view in their original scale; to aid with visualization the previews have been enlarged and smoothed. Cubes and uncertainty cubes are listed for the modes available (SL, LL, SH, LH). For 70 of the 75 galaxies, full three-dimensional spectral cubes in FITS format for all the modules are delivered.
The IRS ascii spectra data available for download are listed based on the IRS mode, which is stripped out of the file name of that dataset [Short-Low => SL, Short-High => SH, Long-Low => LL, etc]. For each spectrum a link to the ascii table version is listed first, followed by a link to the JPEG preview (created by IRSA using the the unix "graph" tool.)
Both Low-resolution and High-resolution, one-dimensional (1D) spectra of the central 23"x15" (High-res) to 50"x33" (Low-res) are delivered for each of the 25 galaxies, in the wavelength range 5-15 mm (Short-Low, SL, R=50-100), 15-37 mm (Long- Low, LL, R=50-100), 10-20 mm (Short-High, SH, R=600), 20-37 mm (Long-High, LH, R=600). The fluxes are calibrated in MJy sr-1. The data are provided as multiple ASCII files (.tbl).
IRS Low-Res 1D spectra: ngcXXXX_DR5_MD#_nuc_sp.tbl (MD=SL,LL; #=1,2). IRS High-Res 1D spectra: ngcXXXX_DR5_MD_nuc_sp.tbl (MD=SH,LH)
On the lefthand side, a grayscale plot of the SH_nuc (Short-High, R=600) spectrum has been created for preview purposes by IRSA, also using the unix "graph" tool. This image can be seen in full resolution by clicking on the small thumbnail on the Summary page.
If available a link is given to the IRS Extranuclear Summary page.
IRS Extranuclear
Also delivered are IRS 3D spectral cubes, 2D maps and 1D spectral extractions for 88 extra-nuclear regions in 22 galaxies. Summary pages are created seperately for these 22 galaxies. The summary layout is sectioned off for each of the extranuclear regions, starting at region 00; within each section are 2D images (FITS), the 3D spectral cubes (FITS) and 1D ascii spectra. (See IRS section above for more details on these three types of data.)
On the lefthand side, a grayscale plot of the SH_sp (Short-High, R=600) spectrum has been created for preview purposes by IRSA, also using the unix "graph" tool. This image can be seen in full resolution by clicking on the small thumbnail on the Summary page.
