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Nara, June 03 Solar neutrino production rates by heavy ion reactions T. Motobayashi (RIKEN) 7 Be(p, ) 8 B reaction pp chain in the sun direct measurement of S 17 c.f. Snover Indirect methods Coulomb dissociation ”ANC” method 8 B Coulomb dissociation experiments RIKEN - 1, 2, MSU MeV/nucleon GANIL - 1, MeV/nucleon Summary / discussions

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Nara, June 03

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1990

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Nara, June 03 8 B+ 208 Pb 7 Be+p+ 208 Pb (C.D.) virtual photon theory or DWBA 8 B( ,p) 7 Be (abs.) detailed balance 7 Be(p, ) 8 B (capt.) large thick target (intermediate energy) experiments with R.I. beams Coulomb dissociation

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Nara, June 03 detailed balance virtual photon number (intermediate energy) thick target charged particle detection indirect i.e. nucl. force / higher order / E2

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Nara, June 03 E rel <= p p, p 7Be, p-Be E rel : Independent of E in E rel =200 keV p+X, T 0 =100 AMeV, E rel =1 MeV, =0.5 deg. v=1%

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Nara, June RIKEN ~50 MeV/nucleon

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Nara, June 03 RIKEN-I (94) RIKEN-2 (98)

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Nara, June 03 Questions Nuclear contribution (E1) small but l=2 ? Higher order effects Different multipolarities 7 Be(p, ) 8 B E1 + M1 (4-15 %) + E2 ( 1%) 208 Pb( 8 B,p 7 Be) 208 PbE1 + E2 (4-15 %) + M1( 1%) angular ( 8 ) distribution angular correlation

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Nara, June 03

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RIKEN-2 small E2 (l=2)

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Nara, June 03 microstrip 2 x PPAC (2nd GSI 254 MeeV/nucleon

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Nara, June 03 E rel (MeV) d /dE (mb/MeV)

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Nara, June 03 transverse momentum distributions consistent with small E2 contribution

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Nara, June 03 azimuthal- / polar-angle distributions

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Nara, June 03 S 17 (eV b) Coulomb dissociationrecent direct capture (+ GSI-2)

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Nara, June 03 parallel momentum distribution (MSU) Davids et al., Phys. Rev. Lett. 81 (1998) 2209

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Nara, June 03 possible corrections Multipolarities E1 dominance: OK in 90% for Coul. Diss. E2 : controversy ? angular distribution (RIKEN) small P // distribution (MSU) 10-15% Angular correlation (GSI) small M1: only at the resonance Nuclear contribution 1% (E1) microscopic calc. large ? (E2) <- collective form factor --> calc.w. microscopic f.f. / CDCC / exp. Higher order effects Post Coulomb acceleration: small multistep excitation: E1-E2 interference --> dynamical calc. / CDCC

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Nara, June 03 C > N C ~N l = 1 l = 2

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Nara, June 03 Asymptotic Normalization Coefficient (ANC) Method 7 Be(p, ) 8 B 7 Be(d,n 8 B tail amplitude of w.f.: weak potential parameter dependence

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Nara, June 03 Analysis: Ogata, Yahiro, Iseri, Kamimura Phys. Rev. C 67 (2003)

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Nara, June 03 S 17 at E=0 RIKEN-1 RIKEN-2 GSI-1 GSI-2 MSU Beijing TAMU-1 TAMU-2 Ogata et al. (2003)

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Nara, June 03 Summary Indirect determination of S 17 Coulomb dissociation ANC in 10-15% agreement with direct-capture results For better accuracy control of reaction mechanism nuclear force higher-order process E2-related corrections RI-beam theory experiment

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