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WS09/10 Mahnke 8.12.09
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.
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
Mars mission: Mössbauereffect on MarsMars mission: Mössbauereffect on MarsMars Exploration Rover MER
WS09/10 Mahnke 8.12.09
Mars mission: Mössbauer effect on MarsMars mission: Mössbauer effect on Mars
Electromagnetic interaction (γ-decay, hyperfineinteraction)
WS09/10 Mahnke 8.12.09
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)
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
Geology – Dating – ArchaeologyAccelerator- mass spectroscopyGeology – Dating – ArchaeologyAccelerator- mass spectroscopy
C-14 Dating on „ice-man“ Ötzi
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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)
WS09/10 Mahnke 8.12.09
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)].
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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 )
WS09/10 Mahnke 8.12.09
Radioactive decay chains for U-238 and Th-232
additional: Np-237 (“died out”), U-235 (4n+i, i=0,1,2,3)
WS09/10 Mahnke 8.12.09
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)
WS09/10 Mahnke 8.12.09
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
WS09/10 Mahnke 8.12.09
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.)
WS09/10 Mahnke 8.12.09
Accelerator - Mass spectroscopyAccelerator - Mass spectroscopy
Shroud of Turin
(W.Kutschera et al.)
WS09/10 Mahnke 8.12.09
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: [email protected]. Dr. H.-E. Mahnke Tel. 8062-2715 (HZB) email: [email protected]
Practical course:Wednesday 12 - 13