UVEX optical configuration if you use a 1800 l/mm grating and a F/10 input beam (ThorLabs grating, blaze 500 nm) :
It is nearly the max. spectral resolution configuration for UVEX.
The incidence angle on the grating is 24,3°, the diffraction angle (for Halpha) is 51,3°. The anamorphic factor is cos(24,3) / cos(51,3) = 1,46, so the wide of the 23 microns slit (physical) is 1,46 x 23 = 34 microns. The measured spectral resolution power at Halpha level is R=7200 (just half of a Lhires III 2400 lines/mm spectrograph).
Some spectra (H2O telluric lines removed) :
Christian B.
UVEX (1800 l/mm grating)
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Re: UVEX (1800 l/mm grating)
Test of the 1800 l/mm grating for the UV/blue spectral region.
By using a 23 microns slit and a F/10 telescope, the spectral resolution is about R = 4200 at 400 nm.
Aspect of the classical Vega profile:
Deneb (sharp spectral lines):
Be stars:
(note resolved emission lines on the Balmer jump)
Symbiotic stars (of course, very faint UV continuum):
(Note: by comparison with a RC telescope of a old C8, the C9.25 StarLight optic absorb significantly the UV flux (specific AR coating)).
Christian
By using a 23 microns slit and a F/10 telescope, the spectral resolution is about R = 4200 at 400 nm.
Aspect of the classical Vega profile:
Deneb (sharp spectral lines):
Be stars:
(note resolved emission lines on the Balmer jump)
Symbiotic stars (of course, very faint UV continuum):
(Note: by comparison with a RC telescope of a old C8, the C9.25 StarLight optic absorb significantly the UV flux (specific AR coating)).
Christian
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Re: UVEX (1800 l/mm grating)
Merci pour ces reports Christian.
Pour les comètes tu penses que l'UVEX est meilleur que l'Alpy ? (je ne sais pas si le terme est bon mais permet il de résoudre mieux les spectres que l'Alpy dans les bandes de Swan avec une résolution meilleure ?)
Pour les comètes tu penses que l'UVEX est meilleur que l'Alpy ? (je ne sais pas si le terme est bon mais permet il de résoudre mieux les spectres que l'Alpy dans les bandes de Swan avec une résolution meilleure ?)