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ESPaDOnS: examples of spectra http://webast.ast.obs-mip.fr/magnetisme/espadons_new/spectra.html
Solar spectrum, Balmer lines
ESPaDOnS
examples of spectra
To collect solar photons with ESPaDOnS, light from the Sun was simply redirected to the instrument aperture with a flat
mirror. A large size silica lens was also added in the beam to make it diverge and avoid chip saturation in exposure times of a
few seconds. Although this was enough to obtain a reasonably well exposed solar spectrum, the absence of motorised drive to
compensate for the Earth rotation forced us to manually redirect the beam towards the instrument every 30s or so and
prevented us from carrying polarimetric experiments (requiring a very stable light injection on time scales of at least 5
minutes).
The full optical spectrum of the Sun was recorded and processed with Libre-ESpRIT. A few portions of the reduced solar
spectrum are presented below, starting with Balmer lines. Among the first five of the series (from Halpha to Hepsilon) present
in the ESPaDOnS spectra, only the first two are included here for illustration purposes:
Solar spectrum @ Halpha Solar spectrum @ Hbeta
Note that in both cases, the lines appear in the overlap regions of two consecutive orders. Rather than being concatenated, the
orders are displayed on top of each other (the straight crossing segment being due to the plotting routines going back to the first
wavelength of the following order). This illustrates in particular how well the two consecutive orders match throughout their
overlap region, both in intensity and wavelength.
Solar spectrum, selected regions
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