HST and FUSE DADS retrievals will be down from Tuesday, September 2 through Wednesday Sept 3 for a DADS/OPUS installation. See list of alternative data sources.
During part of this time, the database will also be down and so searches will be down during that time (HLA and GALEX are unaffected by this downtime).
IMAPS-1 Wavelength Calibration
The IMAPS-1 wavelengths were generated using an IDL routine (wave1.pro)
which requires as input, the x and y pixel location,
and the order number and wavelength, of one spectral feature identified
in the IMAPS image. Based on this one fiducial wavelength, the program
generates a wavelength array for each order. The starting wavelength
and wavelength increment are then stored in the binary table extension
contained in the coadded image FITS file.
The table below shows the wavelength (in Å ), order number, echelle
position (1-4), x & y position (in pixels),
and the line identification for the fiducial spectral feature used
in each of the coadded, corrected IMAPS-1
images. Since these line identifications are the basis for
the IMAPS-1 wavelength calibrations, any errors in these
values would affect the wavelength calibration for that particular image.
Note that no other wavelength corrections have
been applied to the IMAPS-1 files, and the source of the
absorption line used determines the wavelength reference frame.
For example,
since most of the files use interstellar lines, the
wavelength assignments would correspond to
an interstellar reference frame.
Note telluric lines were used for a few files.
Data Reduction & Analysis