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From (DIRCA to) NABONA to CIRCE

C hallenge for L aboratory nuclear- A strophysics in U nderground and S urface 2009 : CLAUS2009. From (DIRCA to) NABONA to CIRCE The path of the Naples-Caserta The story of an exciting scientific Nuclear Astrophyiscs group process and human experience

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From (DIRCA to) NABONA to CIRCE

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  1. Challenge for Laboratory nuclear-Astrophysics in Underground and Surface 2009: CLAUS2009 From (DIRCA to) NABONA to CIRCE The path of the Naples-Caserta The story of an exciting scientific Nuclear Astrophyiscs group processand human experience Filippo Terrasi CIRCE - Environmental Science Department, Second University of Naples, Caserta and INFN, Naples, Italy G. Oliviero

  2. The beginning of the story ….. a “gentle” reaction g A A It was “only” 35 years ago !!

  3. Proton resonant and direct capture on 28Si. Nucl. Phys. A324(1979)1. May 1978 – EPS Conference - Hvar “…. I don’t like to come to Italy: there are too many germans”

  4. 1977: installation of the TTT3 tandem in Naples Theoreticalphysicsdept ZOO Accelerator building The path of another process ….?

  5. 1978: Bernard Gonsior’s sabbatical in Naples The hard case of 40Ca(p,g) Proton direct capture on 40Ca. Nucl. Phys. A394(1983)405.

  6. 1977: installation of HVEC TTT-3 tandem accelerator 1986: start of the AMS project; installation of sputtering source and switching magnet 1987: construction and installation of Wien filter and final detector 1990: modification of analysing magnet vacuum chamber; installation of side Farady cups ……… Non dedicated “home made” AMS system at the Dept. of Physics of the University of Naples “Federico II” (limited throughput and accuracy):

  7. The second part of the story: • The number of germans in Italy decreased • A meeting in Naples with Gianni, Piero and Claus • A discussion in Bochum drawing in the snow • ( Lucio’s PhD in Bochum) • A workshop at LNGS The NABONA experiment NAples BOchum Nuclear Astrophysics

  8. Water Cherenkov chlorine gallium • The solar neutrino problem before SNO • no proof for • oscillations • nuclear solution? pp 13N 15O pep 7Be 7Be 8B hep

  9. Bad absolute cross section factor 3 in S(0) High g background delayed a detection; indirect methods (CB) Problems: 1) Target production and control (stoichiometry) 2) 7Be activity (Eg=.478 MeV, T1/2 = 53 d Ecm Ex(MeV) Jp ER=640 keV 0.78 1+ DC-0 7Be+p Q=0.14 MeV g.s. Jp Ex(MeV) 2+ 8B (t =0.77 s) 2+ EC delayed a-decay g.s. 0+ 2a 8Be INVERSE KINEMATICS REACTION: 1H (7Be, g) 8B Use the AMS system as a recoil separator RIB gas target

  10. p(7Be,g)8B Ecm = 1 MeV 7Be cathode produced by 7Li(p,n) reaction and hot chemistry purification • Ir=fqerNbNpleffNs(Eeff) Singles ! 7BeO- • IS=NbNpleffbWlabscm,b(q,Eeff) Wcm/Wlab s(Eeff)  Ir/ Is (rel. meas.!) F3+=15% HV=2.418 MV 7Be3+ 8 Me V er = 100 3% Beam suppression: 10-10 F4+=67% 7Be4+ F5+=652% (Dp/p)wf=2.6% 8B5+ p=5mbar 8B (Dp/p)sw=1.9% lb=3768mm

  11. 7Be(p,g)8B 990keV The NaBoNA experiment DEres[channel] “leaky” beam 8B recoils .. .. ... ... . . .. What about a coffee tedesco ? “Give him a chance” ! “it’s 7 a.m; we should tell our wives we’ll be late for dinner” Eres[channel] L. Gialanella et al.; Europhys. Jou. A7(2000)303

  12. H(7Be,g)8B reaction: measurement of s(Ecm=0.99 MeV) absolute normalization point for S(E): • 7Be beam 107-108 pps; q=4+ • H2 windowless gas target p=5 mbar • Independent measurement of sel.sc.(q) • Recoil Mass separator transmission: (100±3)% (p(12C,g)13N test measurement) • Recoil Mass Separator suppression factor 1010 • Average 8B charge state from charge state distribution vs. p • N8B = 13 ± 4 (28% statistical error) sR(0.99MeV) = 400 ± 120 nb Large stastistical error but first direct model-independent measurement S17(0) = 16 ± 5 eV b

  13. From NABONA to ERNA Radioactive qr>qb Stable qr<qb low Q-value high Q-value Enhanced angular acceptance Enhanced momentum acceptance Enhanced beam suppression Beam purification Compact (jet) gas target Modified optics (4” gaps) Diapositiva 23 Different layout (WF+mag+WF) Diapositiva 24 Purification W.F.’s on beam line Diapositiva 25 0.2° 1.2°

  14. ERNA at Bochum

  15. Κίρκη Aeaea island Dosso Dossi (Giovanni di Niccolo Luteri)"Circe", c. 1522-1524, canvas, Galleria Borghese, Rome Circe and Odysseus

  16. 29/01/2005 2/02/2005 28/01/2005 25/01/2005 3/02/2005 19/01/2005 28/02/2005 14/02/2005 17/1/2005 14/02/2005 … . 15/01/2005 Center forIsotopicResearch onCultural and Environmental heritage a s e r t a DSA-SUN

  17. Carbon 14 dating at CIRCE Precision <.3% Machine background >62 ka Throughput several hundreds samples/year Accelerator: NEC-Pelletron (3MV)

  18. Carbon 14 dating at CIRCE

  19. Another path ….

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