Research topics: Research topics


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Research topics:

  • Research topics:

  • Experimental and theoretical nuclear physics

  • Atomic physics

  • Ion beam analysis

  • Environmental science

  • Solid state physics

  • etc…





Nuclear reactions

  • Nuclear reactions

  • Main sequence stars: hydrogen burning

  • Conversion of 4 protons into one 4He

  • pp-chain(s)





Sun

  • Sun

















Barrier penetration  steeply (exponentially) dropping cross section

  • Barrier penetration  steeply (exponentially) dropping cross section

  • S-factor: smoother energy dependence

  • Contains nuclear physics

  • Easier to extrapolate





Low cross section  low count rate

  • Low cross section  low count rate

    • High intensity beams
    • Long measurements
    • Background reduction
  • Cosmic rays are difficult to avoid  let’s go underground

















74Se

  • 74Se

  • 78Kr

  • 84Sr

  • 92Nb

  • 92,94Mo

  • 96,98Ru

  • 102Pd

  • 106,108Cd

  • 113In

  • 112,114Sn

  • 120Te

  • 124,126Xe

  • 130,132Ba

  • 138La

  • 136,138Ce

  • 144,146Sm

  • 156,158Dy

  • 162Er

  • 168Yb

  • 174Hf

  • 180Ta

  • 180W

  • 184Os

  • 190Pt

  • 196Hg



Secondary process

  • Secondary process

  • Gamma-induced /mainly (,n)/ reactions on s- and r-process seed isotopes (-process)

  • High temperature needed: supernova explosions





~ 2000 isotopes ~ 20000 reactions

  • ~ 2000 isotopes ~ 20000 reactions

  • Mainly (,n), (,), (,p) reaction and beta decays

  • The models are

  • not able to

  • reproduce the

  • observed

  • p-isotope

  • abundances





Alpha-induced reactions: 5-15 MeV

  • Alpha-induced reactions: 5-15 MeV

  •  Cyclotron







Solar composition problem: contradiction between

  • Solar composition problem: contradiction between

    • Helioseismology (high precision)
    • Solar model, supported by neutrino detection (high precision)


Many astrophysical processes involve short-lived radioactive nuclei





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