Nuclear Astrophysics at the Darmstadt superconducting electron linear accelerator SDALINAC

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Nuclear Astrophysics at the Darmstadt
superconducting electron linear
acceleratorS-DALINAC

• N. Pietralla and K. Sonnabendfor the SFB 634
• Workshop on European Small-Scale Accelerator
  Facilities
• Aghios Nikolaos, Crete, Greece
• September 7th to 8th, 2007
• supported by the DFG under grant No. SFB 634

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Accelerator hall of the S-DALINAC
electron energies from 2 to 130 MeV available
cw and pulsed beam operation possible source
for polarized electron beams under construction
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HIPS High-intensity photon setup
Activation with continuous-energy bremsstrahlung
300 Ng
Ng 105 g / (keV s cm2)
photon energies up to 11 MeV available
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LCS Laboratory for counting and spectroscopy
Determination of activation yield with
g-spectroscopy
three low-energy photon spectrometers (LEPS)
four 30 and 40 HPGe detectors setups with
passive Cu and/or Pb shielding
complementation with x-ray detectors and
electron counters
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LCS Laboratory for counting and spectroscopy
Sample decay spectra LEPS versus HPGe
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NEPTUN High-resolution photon tagger
High-resolution cross section measurements
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NEPTUN High-resolution photon tagger
Determine (g,n) cross sections with 100 keV En
10 MeV
high-resolution cross section measurements
determination of angular momentum of
neutrons (g,p) and (g,a) in preparation
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QCLAM Large-acceptance spectrometer
(e,ex) experiments of astrophysical interest
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QCLAM Large-acceptance spectrometer
momentum resolution Dp/p 2 ? 10-4 solid
angle acceptance 35 msr max. central
momentum 200 MeV/c momentum acceptance
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clamshell dipole magnet (deflection angle
120) quadrupole magnet three multiwire
drift chambers plastic scintillation and
plexiglas Cherenkov counters
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QCLAM Large-acceptance spectrometer
Electron scattering at 180 deflection angle
momentum resolution Dp/p 2 ? 10-4 solid
angle acceptance 6.4 msr max. central
momentum 95 MeV/c momentum acceptance
-5 to 8
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QCLAM Large-acceptance spectrometer
Recent results on M1 deuteron break-up
high energy resolution and high selectivity of
M1 states precision test of modern theoretical
models (potential model, EFT) prediction of
p(n,g)d cross section at Big Bang energies
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QCLAM Large-acceptance spectrometer
Role of neutrino-induced reactions
high resolution (e,e) data ? M1 strength
distribution
? GT0 from shell-model calc.
? n-nucleus cross section
properties of pre-collapse core supernova shock
revivalexplosive nucleosynthesis

• branching ratios of 12C(e,e)
• electro-weak theory
• (n,n) cross sections
• nucleosynthesis of 9Be and 10B

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Experimental hall of the S-DALINAC