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s ( E ) = S(E) e –2 ph E -1

Carlo Broggini INFN-Padova. LUNA, the Sun and the other stars. Stellar Energy+Nucleosynthesis. Hydrogen Burning. s (E star ) with E star << E Coulomb. s ( E ) = S(E) e –2 ph E -1. 2 ph = 31.29 Z 1 Z 2 m/E. m = m 1 m 2 / ( m 1 + m 2 ). . Reaction Rate(star) . F (E) s (E) dE. s.

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s ( E ) = S(E) e –2 ph E -1

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  1. Carlo Broggini INFN-Padova LUNA, the Sun and the other stars • Stellar Energy+Nucleosynthesis • Hydrogen Burning • s(Estar) with Estar << ECoulomb s(E) = S(E) e–2phE-1 2ph = 31.29 Z1Z2m/E m = m1m2 / (m1+m2)  Reaction Rate(star) F(E) s(E) dE s Meas. Extrap. Gamow Peak S(E) Maxwell Boltzmann s

  2. Laboratory for Underground Nuclear Astrophysics Beam: H,He Voltage Range :50-400 kV Output Current: ~1 mA Absolute Energy error ±300 eV Beam energy spread: <100 eV Long term stability (1 h) : 5 eV Terminal Voltage ripple: 5 Vpp Ge detector

  3. Hydrogen burning in the Sun @15*106 degrees: 6*1011 kg/s of H He +0.7% MH E H+2H burning in proto-stars @106 degrees Resonance? activation=prompt gamma s at low energy with 4% error

  4. 3He (3He,2p)4He Q = 12.86 MeV Epmax= 10.7 MeV Suppression of 7Be and 8B e due to a resonance? smin=20 fb (2 events/month) No resonance at the Gamow peak Neutrino oscillations

  5. 14N(p,g)15O Q=7.3 MeV £ turnoff •  F  S1,14 cno Blue Red • Globular Cluster Age Surface colour AgeCluster=F(£turnoff) S(0)=3.5-1.6+0.4 keV b (Ad98) S(0)=3.2-0.8+0.8 keV b (An99) £to=F(S1,14)

  6. 278 “High” energy: solid target + HpGe 7556 1/2+ 7297 14N(p,g)15O 7276 7/2 + gamma spectrum of 14N(p,g)15O at 140 keV beam energy 14N+p 6859 5/2 + -21 6793 3/2 + - 504 6176 3/2 - 5241 5/2 + 5183 1/2 + Low energy: gas target + BGO 15O 0 1/2 - beam energy 90 keV

  7. St(0)=1.57±0.13 keV b *½cno from the Sun * Globular Cluster age +1Gy * more C at the surface of AGB Solar composition problem: Z/X ~0.024 ~ 0.018 SSM predictions disagree with Helioseismology results cno=f(Z,S14), ~30% decrease from high to low metallicity From a measurement of cno from the Sun Metallicity of the Sun core (C+N) Photosphere and core metallicity equal?

  8. LUNA beyond the Sun:isotope production in the hydrogen burning shell of AGB stars (~30-100 T6), Nova nucleosynthesis (~100-500 T6) and BBN 15N(p,g)16O Q=12.13 MeV 25Mg(p,g)26Al Q=6.3 MeV 17O(p,g)18F Q=5.6 MeV 2H(α,g)6LiQ=1.47 MeV 17O(p,α)14N Q=1.2 MeV 22Ne(p,g)23Na Q=8.8 MeV 18O(p,g)19F Q=8.0 MeV 18O(p,α)15N Q=4.0 MeV 23Na(p,g)24Mg Q=11.7 MeV ............

  9. LUNA beyond the Hydrogen burning: 3.5 MV accelerator mainly devoted to Helium-Burning (in stars: ~100 T6, ~105 gr/cm3) 12C(a,g)16Othe most important reaction of nuclear astrophysics: production of the elements heavier than A=16, star evolution from He burning to the explosive phase and ratio C/O 13C(a,n)16O, 22Ne(a,n)25Mgthe stellar sources of the neutrons responsible for the S-process (a,g) on14N, 15N, 18O…… June 2012: accelerator+site preparation financed by the Italian Ministry of University and Research with 2.8 ME ‘Starting the LUNA-MV Collaboration’, LNGS, February 6th-8th 2013

  10. 3He (3He,2p)4He: sdown to 16keV • no resonance within the solar Gamow Peak • 3He(,g)7Be: 7Be ≈promptg Cross section measured with 4% error • 14N(p,g)15O: sdown to70keV • cnoreduced by  2 with 8% error Sun core metallicity • Globular cluster age increased by 0.7-1 Gy • More carbon at the surface of AGB stars • 15N(p,g)16O: sdown to70 keV, reduced by  2 • 25Mg(p,g)26Al: first measurement of the 92 keV resonance, • strength ωγ=(2.9±0.6)x 10-10 eV • 17O(p,g)18F: rate uncertainty @ Novae temperature reduced to 5% • uncertainty on 18O, 18F and 19F less than 10% (from 40-50%) • Future:Hydrogen and Helium burning (3.5 MV accelerator)

  11. 3He(,g)7Be Q=1.6 MeV • Solar Neutrinos: 7Be,8B • F  S34 • BBN 7Li

  12. s down to 93 keV • 7Be ≈ prompt g • S34(0) = 0.567  0.018 keV barn

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