| Pumping | | |
1 | | | |
| Relaxation | | |
2 | | 17.8 (He) 58 () | Rate constant equals cross section
multiplied by the average thermal velocity |
| Lasing | | |
3 | | | |
| Spontaneous
emission | | |
4 | | | |
5 | | | |
| Quenching | | |
6 | | 0.01 (He and ) | |
7 | | same as 6 | |
| Photoexcitation | | |
8 | | | Ref. [14] |
| Energy pooling | | |
9 | | | Ref. [14] |
| Spontaneous
emission | | |
10 | | | |
12 | | | |
13 | | | |
14 | | | |
15 | | | |
16 | | | |
17 | | | |
18 | | | |
19 | | | |
| Photoionization | | |
20 | | | Ref. [14] |
| Penning
ionization | | |
21 | , total 10 reactions | | Ref. [14] |
| Recombination | | |
22 | | | |
23 | | | |
24 | | | , or |
25 | | | |
26 | | | |
| Quenching of the higher
levels | | |
27 | | | |
28 | | | |
29 | | | |
30 | | | |
31 | | | |
32 | | | |
33 | | | |
34 | | | |
| Electron heating and energy
losses | | |
35 | | | Refs. [15] and [20] |
36 | . | | Ref. [21] |
37 | | | Refs. [18] and [19] |