THE SPECTRUM OF VEGA
12th June 2004
VC200L at f6.3 + Vesta SC3 webcam + 100 l/mm grating at 19.4 A/pixel 0.2sec
Vega shows strong Hydrogen Balmer absorption lines typical of spectral type A and so is useful for calibrating the spectrometer.
Because a slitless set up was used, the spectrum is projected onto the sky background (bright at this time of year) Also beyond 750 nm, the blue end of the second order spectrum starts to overlap and interfere with the first order. To reduce these effects, a second spectrum covering IR was recorded using an IR pass filter. This lowered the background interference considerably and enabled the spectrum to be extended to approximately 950nm.
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