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Nucleosynthesis and formation of the elements
IA VIIIB
1.00 1
H 1
IIA IIIB IVB VB VIB VIIB 4.00 2
He 0
6.94 3
Li 1
9.01 4
Be 2
10.8 5
B 6
12.0 6
C –4 –2 0
4
14.0 7
N –3 0 3 5
16.0 8
O –2 0
19.0 9
F –1
20.2 10
Ne 0
23.0 11
Na 1
24.3 12
Mg 2
IIIA IVA VA VIA VIIA VIIIA IB IIB 27.0 13
Al 3
28.1 14
Si 4
30.1 15
P –3 5
32.1 16
S –2 0 4 6
35.5 17
Cl –1
40.0 18
Ar 0
39.1 19
K 1
40.1 20
Ca 2
45.0 21
Sc 3
47.9 22
Ti 4
50.9 23
V 5
52.0 24
Cr 3
54.9 25
Mn 4 3 2
55.8 26
Fe 2 3
58.9 27
Co 2 3
58.7 28
Ni 2
63.5 29
Cu 1 2
65.4 30
Zn 2
69.7 31
Ga 3
72.6 32
Ge 4
74.9 33
As 3,5
79.0 34
Se –2 0 4 6
79.9 35
Br –1
83.8 36
Kr 0
85.5 37
Rb 1
87.6 38
Sr 2
88.9 39
Y 3
91.2 40
Zr 4
92.9 41
Nb 3 5
95.9 42
Mo 4 6
98 43
Tc 7
101 44
Ru 3 4
103 45
Rh 2 3 4
106 46
Pd 2 4
108 47
Ag 1
112 48
Cd 2
115 49
In 3
119 50
Sn 4,2
122 51
Sb 3,5
128 52
Te –2 0 4 6
127 53
I –1
131 54
Xe 0
133 55
Cs 1
137 56
Ba 2
139 57
La 3
178 72
Hf 4
181 73
Ta 5
184 74
W 4 6
186 75
Re 7
190 76
Os 3 4
192 77
Ir 2 4 6
195 78
Pt 2 4
197 79
Au 1 3
200 80
Hg 2
204 81
Ti 1 3
207 82
Pb 2
209 83
Bi 3 5
209 84
Po 2 4
210 85
At –1
222 86
Rn 0
223 87
Fr 1
226 88
Ra 2
227 89
Ac 3
140 58
Ce 3
141 59
Pr 3
141 59
Nd 3
145 61
Pm 3
150 62
Sm 3
152 63
Eu 3
157 64
Gd 3
159 65
Tb 3
163 66
Dy 3
165 67
Ho 3
167 68
Er 3
169 69
Tm 3
173 70
Yb 3
175 71
Lu 3
232 90
Th 4
231 91
Pa 5
238 92
U 4 6
237 93
Np 4 5
244 94
Pu 4
243 95
Am 3
247 96
Cm 3
247 97
Bk
3 4
251 98
Cf 3
252 99
Es
257 100
Fm
258 101
Md
259 102
No
260 103
Lr
Cosmic abundance of the elements
Mass number
-2
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100
log
ab
on
da
nce
(ato
me
s / 1
06 Si)
H
He
Li
Be
B
Fe
Ca
Sc
CO
UTh
PbPt
Ni
Tc Pm
N
NeSiS
Nucleosynthesis
• Big Bang – ca 12 000 Ma
• Supernova – ca 5 000 Ma
• Condensation of matter and formation of the known elements . . .
In the seconds following theBig Bang
Condensation of matter into p and e–
Formation of the fuel of the stars . . . H et HeT 3 x 109 K
p + e– n + v1H + n 2H + 2H + p 3He + 3He + n 4He +
0E+00
3E+10
1 2 3
Z
Ab
un
dan
ce(a
tom
es /
106 S
i)H
He
1st Generation Stars - H fusion and production of 4He
1H + 1H 2H + + + v 0.422 MeV2H + 1H 3He + 5.493 MeV3He + 3He 4He + 1H + 1H 12.859 MeV
He Fusion in Red Giants (~ 106 to 107 years)4He + 4He 8Be8Be + 4He 12C +
12C burning (<1000 years)12C + 4He 16O12C + 12C 20Ne + 4He +
16O burning (<1 year)16O + 16O 28Si + 4He + 12C + 16O 24Mg + 4He +
End of a Red Giant's life: Si combustion:lasts about 1day
28Si + 4He 32S + 32S + 4He 36Ar + 36Ar + 4He 40Ca + 40Ca + 4He 44Ti + 44Ca + 2
44Ti + 4He 48Cr + 48Ti + 2
48Cr + 4He 52Fe 52Cr + 2
52Fe + 4He 56Ni + 56Fe + 2 56Ni / 56Fe + 4He impossible . . .
Nuclear binding energy maximum
• maximum at 56Fe• after, fusion becomes endothermic• nucleosynthesis beyond 56Fe is by neutron capture and by fission of nuclides with Z > 90 (uranium and transuranics)
http://www.chem.uidaho.edu/~honors/nucbind.html
Supernovaand 2nd generation stars
Supernova remnantsCas A in x-rays (Chandra)
Vela
SN1998bu
Remnant of SN386, with central pulsar (Chandra)
Cygnus Loop (HST): green=H, red=S+, blue=O++
Nucleosynthesis by n and p capture
-2
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100
log
ab
on
da
nce
(ato
me
s / 1
06 Si)
H
He
Li
Be
B
Fe
Ca
Sc
CO
UTh
PbPt
Ni
Tc Pm
N
NeSiS
Fe: producedin the final
stage of fusionElements > Fe:
neuton activationin supernova
Instable
CNO
Fissionable Elements F
Na
Mg
Cl
AlP
K
Ar
V
TiCrMnCo
Equilibriumburning
