9. Line Strength

Question 1

Spectral type O

Answer 1

Blue white stars with few lines
Strong He 11 lines
He 1 absorption lines becoming stronger

Question 2

Spectral type B

Answer 2

Blue white stars
He 1 lines peak at B2
H 1 lines increasing in strength

Question 3

Spectral type A

Answer 3

White stars
Balmer lines strongest at A0; becoming weaker
Ca 11 lines becoming stronger

Question 4

Spectral type F

Answer 4

Yellow white stars
Ca 11 lines strengthen as balmer lines weaken
Neutral metal lines (Fe 1, Cr 1) appear

Question 5

Spectral type G

Answer 5

Yellow (solar type)
Ca 11 lines continue to strengthen
Neutral metal lines getting stronger

Question 6

Spectral type K

Answer 6

Cool orange
Ca 11 lines peak at K0
Spectra dominated by neutral metal lines

Question 7

Spectral type M

Answer 7

Cool red
Spectra dominated by molecular absorption bands (TiO and VO)
Strong neutral metal lines

Question 8

Define degenerate

Answer 8

Quantum states available to an electron which have the same energy