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Nucleosynthesis and formation of the elements. Cosmic abundance of the elements. Mass number. 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 the Big Bang. - PowerPoint PPT Presentation
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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
abon
danc
e(a
tom
es /
106 S
i)
H
He
Li
Be
B
Fe
Ca
Sc
CO
UTh
PbPt
Ni
Tc Pm
NNeSi
S
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 nFormation 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
Abu
ndan
ce(a
tom
es /
106 S
i)H
He
Diagramme Hertzprung-Russel
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
2nd Generation Stars(Our sun today)
Fusion by CNO reaction
12C + 1H 13N + 13N 13C + + + v
13C + 1H 14N + 14N + 1H 15O +
15O 15N + + + v15N + 1H 12C + 4He
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
abon
danc
e(a
tom
es /
106 S
i)
H
He
Li
Be
B
Fe
Ca
Sc
CO
UTh
PbPt
Ni
Tc Pm
NNeSi
S
Fe: producedin the final
stage of fusionElements > Fe:
neuton activationin supernova
Instable
CNO
Fissionable Elements F
Na
Mg
ClAlP K
Ar
V
TiCrMnCo
Equilibriumburning
0.00001
0.0001
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
Li Be B C N F Na Mg Al Si P S Cl K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Rb Sr
ppm
CrustRiversSeawater
0.0000001
0.000001
0.00001
0.0001
0.001
0.01
0.1
1
10
100
1000
ppm
CrustRiversSeawater
