1 / 13

Exploring Stellar Nucleosynthesis Beyond Hydrogen Burning with LUNA

LUNA project studies stellar energy and nucleosynthesis, focusing on hydrogen burning reactions and isotope production in stars. The project investigates various nuclear astrophysics phenomena to enhance our understanding of stellar evolution and the universe.

chun
Download Presentation

Exploring Stellar Nucleosynthesis Beyond Hydrogen Burning with LUNA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

  2. Laboratory for Underground Nuclear Astrophysics Voltage Range :50-400 kV Output Current: 1 mA (@ 400 kV) 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. p + p  d + e+ + ne d + p  3He + g pp chain 3He +3He  a+2p 3He +4He  7Be + g 7Be +p  8B + g 7Be+e- 7Li + g +ne 7Li +p  a + a 8B 2a + e++ ne Proto-stars and BBN 85% In search of the resonance 6% prediction of 7Be solar neutrino flux, opacity dominant error source

  4. 3He (3He,2p)4He Q = 12.86 MeV Epmax= 10.7 MeV Suppression of 7Be and 8B ? min = 0.02 pb

  5. 14N(p,g)15O Q=7.3 MeV E<1.20 MeV  E<1.73 MeV •  F S1,14  cno • Globular Cluster Age S(0)=3.5-1.6+0.4 keV b (Ad98) S(0)=3.2-0.8+0.8 keV b (An99)

  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)=1.61±0.18 keV b *½cno from the Sun * Globular Cluster age +1Gy * more C at the surface of AGB 2005: solar composition problem New study with a ‘clover’ detector of the capture to the ground state St(0)=1.57±0.13 keV b 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 sdown to70keVreducedby factor 2 15N(p,g)16O Q=12.13 MeV down to92keV resonance:the lowest ever directly measured resonance strength 25Mg(p,g)26Al Q=6.3 MeV 2H(α,g)6LiQ=1.47 MeV 17O(p,g)18F Q=5.6 MeV 18O(p,g)19F Q=8.0 MeV 22Ne(p,g)23Na Q=8.8 MeV 23Na(p,g)24Mg Q=11.7 MeV ............

  9. LUNA beyond the Hydrogen burning: 3.5 MV accelerator @Gran Sasso 12C(a,g)16Othe ‘Holy Grail’ of nuclear astrophysics 13C(a,n)16O, 22Ne(a,n)25Mgthe stellar sources of the neutrons responsible for the S-process (a,g) on14N, 15N, 18O…… - Letter of Intent to LNGS 2007 - Round Table @LNGS 2/2011 http://luna.lngs.infn.it/ Proposal

  10. 3He (3He,2p)4He: sdown to 16 keV • no resonance within the solar Gamow Peak • 3He(,g)7Be: 7Be ≈promptg ΔΦ(Be) reducedto 6% • 14N(p,g)15O: s down to 70 keV • 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: s down to 70 keV, reduced by  2 • 25Mg(p,g)26Al: first measurement of the 92 keV • resonance • Future:Hydrogen burning in shell, Helium burning

  11. LUNA INFN - Laboratori Nazionali del Gran Sasso D.Bemmerer,C.Broggini,A.Caciolli,P. Corvisiero,H.Costantini, Z.Elekes, A.Formicola, Z. Fülöp, G.Gervino,A.Guglielmetti, C.Gustavino, G. Gyurky, G. Imbriani, M.Junker, A.Lemut, M.Marta,C.Mazzocchi,R.Menegazzo, P.Prati, V.Roca, C.Rolfs, C.RossiAlvarez,E.Somorjai, O.Straniero,F.Strieder, F.Terrasi,H.P.Trautvetter •INFN : Genova, LNGS, Milano, Napoli, Padova, Torino •Inst.Physik mit Ionenstrahlen, Ruhr-Universität Bochum •Forschungszentrum Dresden-Rossendorf •Atomki Debrecen

  12. 3He(,g)7Be Q=1.6 MeV • Solar Neutrinos: 7Be,8B • F  S34 • BBN 7Li

  13. s down to 93 keV • 7Be ≈ prompt g • S34(0) = 0.567  0.018 keV barn • ΔΦ(B) reduced to 11% • ΔΦ(Be) reducedto 6% (dominant error source: opacity) Borexino

More Related