Environmental Engineering Reference
In-Depth Information
Figure 2.4 Schematic representation of hydrogen reacting with itself in the core of sun. The
successful process is shown on the lower left [25].
In Figure 2.4, small circles are protons (hydrogen) denoted by turning point
radius at 1293 eV,
r
2
¼
1113 f. Mean interproton spacing is 31 800 f
¼
49.9
r
2
,in
suns core, so this picture shows more protons than a scale diagram would (at
1.5
10
7
K) by a factor of about 5
2
¼
25 if we represent the proton size by its
turning point radius, 1113 f. Proton turning point collisions (e.g., lower left pair)
occur for a given proton at rate
f
fcoll¼
¼ v
/
L¼
0.6
10
14
/s, where
L¼
1/(
ns
)
¼
1/
np r
2
¼
8.3 nm
¼
8.3
10
6
fm
¼
7438
r
2. Transient protodeuteron events (one
showninupperleftofthe
field, achieved by tunneling at Gamow probability
T¼
10
8
, but again releasing two protons) thus occur at rate 0.6
10
6
s
1
per
proton. Finally, deuteron formations (see one event in lower left portion of
field,
releasing one electron and one neutrino)
require further reaction probability
T¼
8.0
10
24
. Thus, deuteron formation, per proton, occurs at rate
f
fus
¼
T
T
f
fcoll¼
¼
47.8
10
19
/s, or once every 0.67
10
10
years. So it may be said that the
