LRS Spectral Resolution

The table below shows the performance of the three grisms as measured from the spectra of arc lamps.

  g1 (300 l/mm) g2 (600 l/mm) g3 (holographic grating) e2 (holographic grating)
Dispersion 5 Å/pix # 2 Å/pix # 1.88 Å/pix # 0.74 Å/pix #
Range 4067 - 10700 Å 4280 - 7278 Å 6250 - 9100 Å 4790 - 5850 Å
Resolution
note slit size
Wavelength (Å) Resolution (Å)
with 2" slit
Wavelength (Å) Resolution (Å)
with 1" slit
Wavelength (Å) Resolution (Å)
with 1" slit
Wavelength (Å) Resolution (Å)
with 1" slit
  4358 16.7 4358 4.4 6400 4.1 4790 1.48
  5943 16.6 5085 4.5 6800 4.2 5850 1.42
  7248 16.7 5852 4.7 7200 4.1
  8299 16.6 6678 4.4 8000 4.3
  8786 19.0 7245 4.4 8400 4.5
  10123 22.7 - - 8800 5.3

# NOTE: The pix in these dispersions are assuming 2x2 binning

For the highest resolution modes, the 1" slit, you may wish to consider using binning of 1x1 to double the number of pixels in the resolution element from 2 to 4. This is done by requesting 1x1 binning instead of the standard 2x2 binning. If you wish to request 1x2 binning or 2x1 binning as necessary. The first number is the binning in the dispersion direction and the 2nd number is the binning in the spatial direction. Beware that decreasing the binning will increase the readout time and thus your overhead.







Last updated: Sun, 08 Jan 2012 02:07:33 -0600 caldwell



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