[ General Glossary, Quantum Glossary, Atomic Glossary ]
The Hydrogen Lyman Series

The Hydrogen Lyman Series are the series of transitions between the n = 1 shell (ie. the K-shell) and the n > 1 shells (ie L-, M-, N-shells etc). The lines are those allowed by the selection rules Delta l = +/- 1, Delta j = 0, +/- 1. Given the abundance of hydrogen in the universe, these lines are very common and hence given short-hand, customary names:
Energy (eV)
[Wavelength (nm)]
Ion Lower Config
Upper Config
Notes
10.19881
[121.56736]
HI 1s 2S1/2
2p 2Po1/2
Ly-alpha2
Aki = 6.265x108 s-1
fki = 1.388x10-1
10.19885
[121.56682]
HI 1s 2S1/2
2p 2Po3/2
Ly-alpha1
Aki = 6.265x108 s-1
fki = 2.778x10-1
12.08749
[102.57229]
HI 1s 2S1/2
3p 2Po1/2
Ly-beta3
Aki = 1.672x108 s-1
fki = 2.637x10-2
12.08751
[102.57218]
HI 1s 2S1/2
3p 2Po3/2
Ly-beta1
Aki = 1.672x108 s-1
fki = 5.275x10-2
12.74853
[97.25370]
HI 1s 2S1/2
4p 2Po1/2
Ly-gamma2
Aki = 6.818x107 s-1
fki = 9.668x10-3
12.74854
[97.2566]
HI 1s 2S1/2
4p 2Po3/2
Ly-gamma1
Aki = 6.818x107 s-1
fki = 1.934x10-2
13.05450
[94.97431]
HI 1s 2S1/2
5p 2Po1/2
Ly-delta2
Aki = 3.437x107 s-1
fki = 4.648x10-3
13.05450
[94.9729]
HI 1s 2S1/2
5p 2Po3/2
Ly-delta1
Aki = 3.347x107 s-1
fki = 9.296x10-3
etc etc etc

See also Hydrogen Energy Levels or Other Astronomically Important Lines

Things to Note

  • There is actually a pair of allowed transitions for each line.
    • (these are permitted lines)
  • The oscillator strengths are in the ratio of 1:2
    • (due to the different number of states)