DIS information/tips

Variation of line positions with rotator position

(Bill Ketzeback / bketzeback at Here is a link to some (from 2006) tests that show line position varies with rotator angle. Here the high resolution gratings refers to the B1200/R1200 pair but the low/med naming convention was likely referring to the older B300/R300 pair not the current B400/R300 set.

Experience merging the data from blue and red sides

Radial velocity precision

Using slitmasks for mulit-object observations with DIS

Data reduction possibilities

(Karen Kinemuchi / kinemuchi at This attachment is a basic data reduction cookbook and can be used as a guide to obtain 1-d extracted and wavelength calibrated DIS spectra. The main reduction tool is IRAF, and it is assumed the user has some knowledge of the IRAF environment. The user is encouraged to experiment with the parameters in each IRAF task, depending on the user's science goals or specific results from the spectra itself.

APO extinction curve

(Bill Ketzeback / bketzeback at This plot shows extinction as wavelength verses magnitude/airmass over the range of DIS wavelengths. It is derived from SDSS extinction data. It also shows how the local site compares to KPNO and CTIO. The noisy red end from atmospheric effects has been smoothed and clipped. This plot and its data file was compiled by Jim Davenport at U Washington.

B1000: good choice of blue grating

The output of the review of a possible DIS upgrade, 2017

Found here: dis-preliminary-design.pdf

Last modified 2 years ago Last modified on May 8, 2017, 8:16:37 PM

Attachments (4)

Download all attachments as: .zip