Transcript
Page 1: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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

Page 2: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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

Page 3: 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 . . .

Page 4: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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 +

Page 5: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

0E+00

3E+10

1 2 3

Z

Ab

un

dan

ce(a

tom

es /

106 S

i)H

He

Page 6: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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

Page 7: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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 +

Page 8: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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 . . .

Page 9: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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

Page 10: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

Supernovaand 2nd generation stars

Page 11: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

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++

Page 12: Nucleosynthesis and formation of the elements. Cosmic abundance of the elements Mass number

Nucleosynthesis by n and p capture

Page 13: Nucleosynthesis and formation of the elements. 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

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


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