Simulation of photon noise on the resolution boosting effect

Result: EDI indeed behaves like 2.4x higher resolution device

Simulation of the EDI and two conventional instruments observing a doublet, with variable doublet spacing, and same simulated photon noise. This shows a resolution boost of 2.4x, using a single fixed delay. Drag the frame # cursor to change the doublet spacing.

Vertical axis is in percent of continuum. Horizontal axis in wavenumber, near 19,000. The same random noise field on the CCD was used for all three signals. The noise structure on the EDI curve (red) looks slightly different because it includes Moire information which is at different spatial frequency on the CCD. The EDI using a 20k resolution grating behaves similar to the conventional instrument with 2.4 times greater resolution. For more info see Ref. 7 & 8

This demonstrates that the equalization that was used to reshape the effective instrument lineshape into a Gaussian, and which creates a non-white noise distribution, does not prevent the EDI from behaving as a 2.4x boosted spectrograph. site maintained by
David Erskine

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