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ESPaDOnS: examples of frames http://webast.ast.obs-mip.fr/magnetisme/espadons_new/frames.html
Examples of flat field frames
polarimetric configuration (2
fibres and 3 slices per fibre)
ESPaDOnS
examples of frames
Below are some example flat field frames (close-up views) corresponding to different instrument configurations. One can notice
in particular that:
two sets of interleaving orders are present in the left image (polarimetric configuration) while only one set of orders
shows up on the other two images (’object only’ spectroscopic configuration);
the number of slices per spectrum is different for the different setups, each spectrum being divided into 3, 4 and 6
thin stripes on the left, middle and right image respectively, with the two side stripes being slightly weaker than the
middle ones.
’object only’ spectroscopic
configuration (1 fibre and 4
slices per fibre)
’object only’ spectroscopic
configuration (1 fibre and 6
slices per fibre)
Note that the second image corresponds to a configuration not offered for observations as it gives no advantage over the official
’object only’ spectroscopic configuration (1 fibre, 6 slices per fibre) depicted in the third image. It is only displayed here as an
illustration of how ESPaDOnS behaves.
Examples of Th/Ar and Fabry-Perot frames
These are now example comparison frames (close-up views) of different types (Th/Ar and Fabry-Perot) and for 2 different
instrument configurations (polarimetric and object only’ spectroscopic configurations). In addition to what was noted on the
flat field frames above, one can observe here that:
thorium lines are very numerous and rather narrow in the vertical (ie grating dispersion) direction, with a full width
at half maximum of order 1.5 pxl (the exact value being 1.7 and 1.4 pxl for the left and right image respectively);
although wider than the thorium lines, the Fabry-Perot interference features are well defined and very regular,
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