Refining Spectrograph Setup

With only a few days to go until the BAA spectroscopy workshop at the Norman Lockyer observatory this Saturday, I thought I’d post a few of my latest spectra.

Here are 4 high resolution spectra of the hydrogen alpha emission line from the B1I star Kappa Cassiopeia. This emission line comes from a high velocity stellar wind which can reach around 1000 km/s.

These spectra were taken on 4 nights in late September. I used them to refine the setup of my LHIRES III spectrograph. The first spectrum on 22nd looks quite noisy, while by the final one on 30th the signal is strong with low noise. I was adjusting the main mirror position, telescope focus and guide focus to improve the light thoughput which increased the signal.

Though the early spectra are more noisy there does appear to be a change in the profile over a few days. A star I’ll be watching closely!

Cheers,

Andy