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1. Introduction: What is Nuclear Physics?It does not fit into the classical scheme (mechanics, acoustics, optics, …). Therefore:

Different principle:According to size (extension, energy, time): structure of matter

elementary particles, nuclear physics, atomic and molecular physicscondensed matter physics (soft-hard)(with increasing number of particles, leading to

„Many particle physics“)

Nuclear physics is governed by the strong force („quarks“), forwhich we do not have a simple, easy-to-handle mathematical form (like the Coulomb law). Adopt and apply (if possible) models and descriptions from other fields (shell model, concept of temperature, superconductivity, pairing).

And vice versa:Use methods and ideas originating from nuclear physics (elementaryparticle physics) in other fields.

1. Introduction: What is Nuclear Physics?It does not fit into the classical scheme (mechanics, acoustics, optics, …). Therefore:

Different principle:According to size (extension, energy, time): structure of matter

elementary particles, nuclear physics, atomic and molecular physicscondensed matter physics (soft-hard)(with increasing number of particles, leading to

„Many particle physics“)

Nuclear physics is governed by the strong force („quarks“), forwhich we do not have a simple, easy-to-handle mathematical form (like the Coulomb law). Adopt and apply (if possible) models and descriptions from other fields (shell model, concept of temperature, superconductivity, pairing).

And vice versa:Use methods and ideas originating from nuclear physics (elementaryparticle physics) in other fields.

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Technical Applications (e.g. energy production – fission-fusion -atomic bomb – nuclear power plant – navigation –topographical surveying, telecommunication)

Cosmology (e.g. Neutrinos from SN87A)

Astrophysics (e.g. Mars exploration: Mössbauerspectroscopy)

Solid state physics (methods originating from nuclear and particle physics, neutron scattering, synchrotron radiation, ion beam analytics)

Geology (e.g. age determination - chronology)

Archaeology, cultural heritage studies (museums)

Biology – medical application

Technical Applications (e.g. energy production – fission-fusion -atomic bomb – nuclear power plant – navigation –topographical surveying, telecommunication)

Cosmology (e.g. Neutrinos from SN87A)

Astrophysics (e.g. Mars exploration: Mössbauerspectroscopy)

Solid state physics (methods originating from nuclear and particle physics, neutron scattering, synchrotron radiation, ion beam analytics)

Geology (e.g. age determination - chronology)

Archaeology, cultural heritage studies (museums)

Biology – medical application

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Mars mission: Mössbauereffect on MarsMars mission: Mössbauereffect on MarsMars Exploration Rover MER

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Mars mission: Mössbauer effect on MarsMars mission: Mössbauer effect on Mars

Electromagnetic interaction (γ-decay, hyperfineinteraction)

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Neutron physicsMünchner Reaktor FRM I und II

Neutron physicsMünchner Reaktor FRM I und II

Fission, Transmutation for doping Si30→Si31→P31, radioactivity

(also at Helmholtz Zentrum Berlin in Wannsee former Hahn-Meitner-Institut)

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500 nm

Cu nanowire Nanowire transistor Filter production

1µm

beam incidence

Nano towers

Ion track technology

Ion beam modificationNon-destructive analysis

by high-energy Proton Induced X-ray Emission

Ion beam analysis

Radiation hardness

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Geology – Dating – ArchaeologyAccelerator- mass spectroscopyGeology – Dating – ArchaeologyAccelerator- mass spectroscopy

C-14 Dating on „ice-man“ Ötzi

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Sky disk of Nebra True or fake? Hostorical background?

Sky disk of Nebra True or fake? Hostorical background?

Copyright: Landesamt für Denkmalpflege und Archäologie Sachsen-Anhalt, Juraj Lipták

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MRT and PET(NMR nuclear magnetic resonance, PET Positron-Emission -

Tomography)

MRT and PET(NMR nuclear magnetic resonance, PET Positron-Emission -

Tomography)

hyperfine interaction physics of antimatter

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Smaller dimensions – higher energies

Compare light microscopy

E=hν=hc/λ c= νλ

E=p2/2m p=ħk=h/λ de Broglie-wavelength

Λ= ħc/mc2 Compton wavelength

Bigger „machines“ !

Accelerators – so-called machine Nobel prizes!!

E.O. Lawrence (Zyklotron) 1939J.D. Cockcroft und E.T.S. Walton (nuclear reactions at accelerators) 1951E. Segrè und O. Chamberlain (anti proton, Berkeley-accelerator) 1959R. Hofstadter (electron scattering at the nucleus, Stanford-accel.) 1961L. Alvarez (hydrogen-bubble chamber at accelerators) 1968B. Richter und S.C.C.Ting (fundamental particles, Stanford and DESY) 1976J.W. Cronin und V.L. Fitch (K-meson-decay) 1980C. Rubbia und S. van der Meer (weak bosons, CERN) 1984

Smaller dimensions – higher energies

Compare light microscopy

E=hν=hc/λ c= νλ

E=p2/2m p=ħk=h/λ de Broglie-wavelength

Λ= ħc/mc2 Compton wavelength

Bigger „machines“ !

Accelerators – so-called machine Nobel prizes!!

E.O. Lawrence (Zyklotron) 1939J.D. Cockcroft und E.T.S. Walton (nuclear reactions at accelerators) 1951E. Segrè und O. Chamberlain (anti proton, Berkeley-accelerator) 1959R. Hofstadter (electron scattering at the nucleus, Stanford-accel.) 1961L. Alvarez (hydrogen-bubble chamber at accelerators) 1968B. Richter und S.C.C.Ting (fundamental particles, Stanford and DESY) 1976J.W. Cronin und V.L. Fitch (K-meson-decay) 1980C. Rubbia und S. van der Meer (weak bosons, CERN) 1984

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1. Basics - TerminologyEnergy, stable and unstable nuclei, transformations by decay, - by reactions, decay law.

Useful units:

1 fm (femtometer) = 10-15 m speed of light (in vacuum) c = 2.998 · 1023 fm/scharge e = 1.602 · 10-19 C

e2/4 π є0 = 1.44 MeV fmfine structure constant α = e2/ ħc = 1/137combined with Planck‘s constant

ħc = 197.3 MeV fm

C-12 mass scale1 AME (amu) = 1/12 M (12C) = 931.478 MeV/ c2

relativistic mechanics:E = mc2 = γm0c2 p = γm0 v

scalar product of a 4-vector formed by energy and momentum (E, pc): → energy law (E, pc) 2 = E2 - p2 c2 = (m0c2 )2

β = v/cγ = 1/(1- β2) ½

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Masses of electron, nucleons, and some atoms.

particle Z N M (MeV) M (amu)

e 0 0 0.511 5.4858·10-4

p 1 0 938.279 1.00727647n 0 1 939.573 1.00866502H 1 1 1876.138 2.0141023H 1 2 2809.4527 3.0160493He 2 1 2809.4340 3.0160294He 2 2 3728.4287 4.0026037Li 3 4 7.016009Be 4 5 9.0121812C 6 6 12(Def.)16O 8 8 15.994915238U 92 146 238.0508

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Constitution of nuclei

Z proton number (element number)N neutron numberA mass number = Z + Nq charge state

Isotopes (Z const)Isotones (N const)Isobars (A const)Isomers (A,Z,N const)

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Bindung energy

The sum of the single masses is larger than the mass of the united(bound) system !

Def. 1: Electron binding energy (total) BZe(Z) , nuclear mass Mk(A,Z) and atomic mass M(A,Z)

Mk(A,Z) + Z me = M(A,Z) + BZe(Z) /c2

example hydrogen : BZ=1e(Z=1) = 13.6 eV

Def. 2: K-,L-, …electron binding energy, e.g. BeK(Z) ,

M+(A,Z) + me = M(A,Z) + BeK(Z) /c2

Def. 3: Nuclear binding energy Bk(A,Z) , B(A,Z), resp.Nuclear mass Mk(A,Z) , Atomic mass M(A,Z)

a. Z mp + N mn = Mk(A,Z) + Bk(A,Z) /c2

b. Z M(H) + N mn = M(A,Z) + B(A,Z) /c2

Def. 4: Separation energy: separating a part (a,z) out of (A,Z)

S(a,z) = [M(A-a,Z-z) + M(a,z) – M(A,Z)] c2 = Bk(A,Z) – [Bk(A-a,Z-z) + Bk(a,z)].

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Bindung energy

Def. 5: Q-value of a reaction or decay

Q = Sum before – sum after = {M(a) + M(A) – [M(B) + M(b)]} c2

Q > 0 exothermal, decay possible, release of energyQ < 0 endothermal, energy input needed

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Energy conditions in nuclear decaysFissionα-decayγ-decayβ-decay (in 4 different variants)p-decayC-14-decay

Decay law

Heisenberg uncertainty principle ∆E ∆t ≈ ħ

constant, characteristic decay probability λ („Tracer“ marker)

Fermi-rule λ= 2π/ ħ |<final state f | Hww |initial state i>|2 ρ(Ei – Ef)

Product of decay constant and actual number is called activity

single dN/dt = - λ N N = No · e - λt

sequential dNi/dt = λi-1 Ni-1 - λi Ni

N1 = No · e – λ1t

N2 = No · λ1 · (λ2 -λ1 )– 1 · (e – λ1t - e – λ2t )

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Radioactive decay chains for U-238 and Th-232

additional: Np-237 (“died out”), U-235 (4n+i, i=0,1,2,3)

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Auger-Electron Cascades

When slow highly charged ions approach a surface: formation and decay of hollow atoms (Stolterfoht et al., Phys. Rev.A 52(1995)445)

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Radioactive tracera) Photo luminescence (PL) of ZnS

b) Doping of CdTe, With radioactive Cd

Electrical detection(Wienecke et al., J. Cryst. Growth 161 (1996)82)

Radioactive tracera) Photo luminescence (PL) of ZnS

b) Doping of CdTe, With radioactive Cd

Electrical detection(Wienecke et al., J. Cryst. Growth 161 (1996)82)

Production of ‘deeply red’ copper centers in ZnS by radioactice decay of Zn-65

I. Broser and K. -H. FrankeJournal of Physics and Chemistry of Solids, 26(1965)1013

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Accelerator mass spectroscopyActivity: λ N

14C: λ = 1/8000 a concentration: 14C/ C-total = 1.2 ·10-12

background (typical) 1 count/min, comparable activity neededNumber of atoms = Activity x mean life

4 ·109 = 1 decay/min x 8000 a

small decay constants (long lifetime) it is better to countatoms rather than decays!

For C, chemistry helps (no stable negative 14N-ion), no interference with 14C (Ion source etc.)

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Accelerator - Mass spectroscopyAccelerator - Mass spectroscopy

Shroud of Turin

(W.Kutschera et al.)

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LITERATURE1) Ch. Berger, "Teilchenphysik", Springer Lehrbuch2) W. Demtröder, "Experimentalphysik 4", Springer Lehrbuch3) Th. Mayer-Kuckuk, "Kernphysik", Teubner Studienbücher4) P. Marmier, E. Sheldon, Physics of Nuclei and Particle, Academic Press, 19695) H. Frauenfelder, E.M. Henley, „Subatomic Physics", 1974, Prentice Hall, Englewood Cliffs

(deutsch Oldenburg 1996) 6) Chr. Lehmann, Interaction of Radiation with solids, series “Defects in Crystalline Solids”,

vol. 10, N-H P C 1977, Amsterdam7) G. Schatz, A. Weidinger, „Nuclear Condensed Matter Physics“, Wiley 1995 (deutsch Teubner)8) B. R. Martin, G. Shaw, „Particle physics“, Wiley, 1997, 2nd edition9) D. H. Perkins, “Introduction to high energy physics”, Cambridge, 2000, 4th edition10) G. Kane, “Modern elementary particle physics”, Addison Wesley, 1993, 2nd edition11) particle data book: http://pdg.lb.gov12) http://cdsmedia.cern.ch/img/CERN-Brochure-2008-001-Eng.pdf

Scriptum and excercises see http://users.physik.fu-berlin.de/%7Eag-heyn/ (FU, Fachbereich Physik, Forschung, exper. Gruppen, Heyn, homepage, teaching)

Adresses:Prof. Dr. M. P. Heyn Tel. 838-56160 email: maarten.heyn@physik.fu-berlin.deProf. Dr. H.-E. Mahnke Tel. 8062-2715 (HZB) email: mahnke@helmholtz-berlin.de

Practical course:Wednesday 12 - 13