Nuclear Physics Study

2009/08/01Grass

From CERN, Summer Student Program 2005

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Do you recognize me?

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Do you recognize me?

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Strong v.s. Electromagnetic

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Radioactivityb- decay: n p + e- + n

b+ decay: p n + e+ + n (e.g., 14O8 14N7 + e+ + n)

a decay: (e.g., 238U8 234Th90 + 4He2 )

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3a reaction : a+a+a 12Cap process : 14O+a 17F+p 18Ne 18Ne+a ...

Capture Process

Proton capture Neutron

capture

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The Liquid Drop ModelTheir interior densities are the sameTheir heats of vaporization are proportional to their masses.

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Magic number

See the movie…

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Shell Model

Including a spin-orbit interaction Predicted magic numbers

1st Shell: 2 states (n = 0, j = 1/2). 2=22nd Shell: 6 states (n = 1, j = 1/2 or 3/2). 8 = 2+63rd shell: 12 states (n = 2, j = 1/2, 3/2 or 5/2). 20 = 2+6+124th shell: 8 states (n = 3, j = 7/2). 28 = 2+6+12+85th shell: 22 states (n = 3, j = 1/2, 3/2 or 5/2; n = 4, j = 9/2). 50 = 2+6+12+8+22 6th shell: 32 states (n = 4, j = 1/2, 3/2, 5/2 or 7/2; n = 5, j = 11/2). 82 = 2+6+12+8+22+32 7th shell: 44 states (n = 5, j = 1/2, 3/2, 5/2, 7/2 or 9/2; n = 6, j = 13/2). 126 =

2+6+12+8+22+32+448th shell: 58 states (n = 6, j = 1/2, 3/2, 5/2, 7/2, 9/2 or 11/2; n = 7, j = 15/2).

184 = 2+6+12+8+22+32+44+58

the nuclear shell model is a model of the atomic nucleus which uses the Pauli exclusion principle to describe the structure of the nucleus in terms of energy levels.

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Nucleosynthesis Paths

The End

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The S-process acting in the range from Ag to Sb.

http://en.wikipedia.org/wiki/S-process

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