kerstin sonnabend, ikp, tu darmstadt s-dalinac - nuclear astrophysics nuclear astrophysics at the...
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Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
Nuclear Astrophysics at the Darmstadt superconducting electron linear accelerator
S-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
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
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
HIPS
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
HIPS – High-intensity photon setup
photon energies up to 11 MeV available
electrons
Emax
0 ≤ E ≤ Emax
0 ≤ E ≤ Emax
n
Au/Re - target
n
11B - target
N ≈ 105 / (keV s cm2)
≈ 300 · N
collimator
radiator
Activation with continuous-energy bremsstrahlung
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
LCS – Laboratory for counting and spectroscopy
– three low-energy photon spectrometers (LEPS)
– four 30% and 40% HPGe detectors
– setups with passive Cu and/or Pb shielding
Pb
Pb
Cu
Cu
LEPS LEPS
Pb Pb
Pb
HPGe
– complementation with x-ray detectors and electron counters
Determination of activation yield with -spectroscopy
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
LCS – Laboratory for counting and spectroscopy
Sample decay spectra: LEPS versus HPGe
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
NEPTUN – High-resolution photon tagger
High-resolution cross section measurements
detectorarray
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
NEPTUN – High-resolution photon tagger
– 14 liquid scintillator neutron detectors
– 8 additional 10B enriched liquid scintillator detectors
– high-resolution cross section measurements
– determination of angular momentum of neutrons
– (,p) and (,) in preparation
Determine (,n) cross sections with 100 keV ≤ En ≤ 10 MeV
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
QCLAM – Large-acceptance spectrometer
(e,e‘x) experiments of astrophysical interest
QCLAM
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
QCLAM – Large-acceptance spectrometer
– clamshell dipole magnet (deflection angle: 120°)
– quadrupole magnet
– three multiwire drift chambers
– plastic scintillation and plexiglas Cherenkov counters
– momentum resolution: p/p = 2 10-4
– solid angle acceptance: 35 msr
– max. central momentum: 200 MeV/c
– momentum acceptance: ±10%
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
QCLAM – Large-acceptance spectrometer
– momentum resolution: p/p = 2 10-4
– solid angle acceptance: 6.4 msr
– max. central momentum: 95 MeV/c
– momentum acceptance: -5% to +8%
Electron scattering at 180° deflection angle
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
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,)d cross section at Big Bang energies
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
QCLAM – Large-acceptance spectrometer
Role of neutrino-induced reactions
properties of pre-collapse core supernova shock revivalexplosive nucleosynthesis
– branching ratios of 12C(e,e‘) electro-weak theory (,‘) cross sections
nucleosynthesis of 9Be and 10B
– high resolution (e,e‘) data M1 strength distribution GT0 from shell-model calc. -nucleus cross section
Shell-Modeltotal
Orbital
Spin
52CrS-DALINAC
excitation energy / MeV
K. Langanke et al., PRL 20 (2004) 202501
B(M
1) /
N
B(M
1) /
N
Kerstin Sonnabend, IKP, TU Darmstadt S-DALINAC - Nuclear Astrophysics
Experimental hall of the S-DALINAC
QCLAM
NEPTUN
HIPS