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Nuclear Physics @ CMAM

Nuclear Physics @ CMAM. Olof TENGBLAD IEM - CSIC. Nuclear Physics Beam Line. Formation of 12 C and 7 Be. Break-up Study of following the reactions 10 B( 3 He,p) 12 C* & 11 B( 3 He,d) 12 C*. Cross section Study of 3 He( 4 He, g ) 7 Be. R&D for future detectors.

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Nuclear Physics @ CMAM

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  1. Nuclear Physics @ CMAM Olof TENGBLAD IEM - CSIC O. Tengblad: CMAM 10 year’s anniversary March 2013

  2. Nuclear Physics Beam Line Formation of 12C and 7Be Break-up Study of following the reactions 10B(3He,p)12C* & 11B(3He,d)12C* Cross section Study of 3He(4He,g)7Be R&D for future detectors O. Tengblad: CMAM 10 year’s anniversary March 2013

  3. Nuclear Structure & Astrophysics • “Exact” A-body calculations possible for A12 • Shell-model states • Molecular-cluster states • We can cover from drip-line to drip-line • Break-up mechanism not fixed by kinematics • Sequential? • Direct? • Crucial for bridging the • A=5 and A=8 gaps in Big Bang and Stellar nuclear synthesis. 12C & The triple alpha process 4He + 4He ↔ 8Be 8Be + 4He ↔ 12C + γ + 7.367 MeV a clustering O. Tengblad: CMAM 10 year’s anniversary March 2013

  4. 1953 1957 1958 1966 12C - The Cosmic Connection O. Tengblad: CMAM 10 year’s anniversary March 2013

  5. Morinaga’s Idea for rotational bands in n nuclei O. Tengblad: CMAM 10 year’s anniversary March 2013

  6. 12C measured @ ISOLDE, JYFL & KVI Measured with high segmentation  decay mechanism / branching Experiment 2002-2004 Measured with implantation method  total energy Experiment april 2006 O. Tengblad: CMAM 10 year’s anniversary March 2013

  7. The Triple Alpha Process r3aGrad e-Q/kT Revised rates for the stellar triple- process from new measurement of 12C resonances Fynbo et.al. Nature 433 (2005) 136-139 (IF: 29,273) O. Tengblad: CMAM 10 year’s anniversary March 2013

  8. A+a  C*  B*+b p 10B 13N*    11B d How to produce the 12C* States @ CMAM 9B* 3He @ 4.9 MeV + 12C* OR 3He @ 8.5 MeV + + 12C* O. Tengblad: CMAM 10 year’s anniversary March 2013

  9. Ea Ep Waggoner et al., NPA 88(1966)81 3He (@ 2,45 MeV)+10B  p O. Tengblad: CMAM 10 year’s anniversary March 2013

  10. back strips a1 4 3 2 1 a2 1 2 3 4 front strips Can we do it better today? • Detection system Developments in Si detectors, especially of the DSSSD the high segmentation of the detectors makes it possible to detect all particles, has improved tremendously the multi particle coincidence detection probability, and thus made possible to kinematically reconstruct each event. • Computer power and analysis capability. • Event by event detection combined with MonteCarlo simulations including both theory and the actual set-up makes possible to extract information about decay mode, branching ratios and other physics parameters. 50x50 mm2 16 front x 16 back strips 3x50mm2 O. Tengblad: CMAM 10 year’s anniversary March 2013

  11. 11B(3He,d) 10B(3He,p) Reaction Studies 3He @ 4.9 and 8.5 MeV Targets: 18.9 mg/cm2 10B 4 mg/cm2 C-backing 22.0 mg/cm2 11B 4 mg/cm2 C-backing  = 38% of 4 O. Tengblad: CMAM 10 year’s anniversary March 2013

  12. Particle Identification 3He + 11B d + 12C* a d p O. Tengblad: CMAM 10 year’s anniversary March 2013 12 DE

  13. E12C (MeV) Ei() (MeV) p +  +  + a coincidences  Excitation Energy in 12C reconstructed Esum=3/2*E1+0.092 MeV SE 12C* 1 8Be(0+) 2 3 We can deduce the partial branching ratios for each level in 12C* via the 0+ and 2+ states in 8Be O. Tengblad: CMAM 10 year’s anniversary March 2013

  14. g-decay of the T=1 level @ 15.11 MeV 3He+10B p+3 punch- throughs 12C excitation Summing 3a 3He+11B d+3 3He+11B n+p+3 12C excitation energy from proton O. Tengblad: CMAM 10 year’s anniversary March 2013

  15. p 10B Indirect Detection of g-decay 3He @ 4.5 MeV g • 17mg/cm2 • (+3 mg/cm2) 15.11 1+ 15.11 1+ 12C* g • The proton gives initial populated resonance in 12C 12.71 1+ • This state can emit g and populate a lower excited state 11.83 2- • The 3alphas give resonance populated in 12C after g-decay ≈10 0+ 7.65 0+ a a a 12C a+a+a 7.65 0+ 12C* O. Tengblad: CMAM 10 year’s anniversary March 2013

  16. g-decay of the T=1 level @ 15.11 MeV M. Alcorta et.al. Phys. Rev. C86, 064306 , (2012) 15.11 1+ 12.71 1+ 11.83 2- ≈10 0+ 7.65 0+ a+a+a M. Alcorta et al, NIM A605, 318-325 (2009) O.S. Kirsebom et al, Phys.Lett B680, 44-49 (2009) Thesis de Martin Alcorta 2010 12C O. Tengblad: CMAM 10 year’s anniversary March 2013

  17. Summary: what have we learned Observation of g-decay and a-decay of T=1 15.11 MeV state 15.11 1+ 15.11 1+ 15.11 1+ g-decay of T=0 12.71 MeV state observed to Hoyle state and to the broad 10 MeV state 14.08 4+ 14.08 4+ E,G 13.35 4- 4- 13.35 (2-) E,G 12.71 1+ 12.71 1+ 13.35 4- Improved measurements of energy and widths for known states 11.1/11.2 0+,2+ 11.83 2- 11.83 2- E,G 11.1/11.2 0+,2+ 12.71 1+ 11.83 2- Branching ratios of decay through the 8Be(gs) were measured for natural parity states 10.84 1- 10.84 1- E,G ≈10 (0,2+) ≈10 (0,2+) 10.84 1- 9.64 3- 9.64 3- G Studied the decay mechanism of the 12.71 MeV resonance using Dalitz plots 9.64 3- 7.65 0+ 7.65 0+  14.08 4+ 4.44 2+ 4.44 2+ Dalitz plots used to determine Jp of 13.35 MeV resonance g.s. 0+ g.s. 0+ 12C 12C Thesis de Martin Alcorta 2010 O. Tengblad: CMAM 10 year’s anniversary March 2013

  18. Nuclear Physics Beam Line Formation of 12C and 7Be Break-up Study of following the reactions 10B(3He,p)12C* & 11B(3He,d)12C* Cross section Study of 3He(4He,g)7Be R&D O. Tengblad: CMAM 10 year’s anniversary March 2013

  19. Motivation for the 3He(4He,γ)7Be cross section measurement • 3He(4He,γ)7Be → source of uncertainty in determining the high energy solar neutrino flux from the reaction 7Be(p,γ)8B • 2.The reaction plays an important role in the 7Li abundance Available data on the astrophysical S factor shows a significant scatter and persistent discrepancy → 0.53(5) keV b used in SSM and 0.54(9) keV b used SBBN for S34(0) O. Tengblad: CMAM 10 year’s anniversary March 2013

  20. Possible experiment 3He(4He,γ)7Be • Activity- 478 keV : • 7Be decays to 7Li • BR=10.45 (4) % • T1/2=53.29 (7) days • Simple setup Prompt-: DC 429, 429  0 Complicated Setup O. Tengblad: CMAM 10 year’s anniversary March 2013

  21. Experimental set-up at CMAM Npbychargeintegration Ntbyenergyloss Target: 4He respectivley3He Scattering foil: 1 mm thick Ni foil Beam: 3He respectively4He Energy: 4 MeV 1+ 7Be Delayed Gamma measurement Nt=9.966 ·1018· l·P/(T+T0) NpbyMonitoring O. Tengblad: CMAM 10 year’s anniversary March 2013

  22. 3He(4He,g)7Be cross section study by induced gradiation • ~900 cts. in 478 peak. • 6 days of counting Thesis Mariano Carmona Gallardo 2013 M. Carmona-Gallardo, et.al. Phys. Rev. C86, 032801, (2012) O. Tengblad: CMAM 10 year’s anniversary March 2013

  23. Nuclear Physics Beam Line Life of stars Formation of12C and 7Be Study of 10B(3He,p)12C* & 11B(3He,d)12C* Study of 4He(3He,g)7Be & 3He(4He,g)7Be Death of stars D. Galaviz Redondo, Centro de Física Nuclear da Universidade de Lisboa Production ofp-nuclei 197Au(a,n)200Tl reaction cross section R&D O. Tengblad: CMAM 10 year’s anniversary March 2013

  24. p-process Studies Production of most rare nuclei in the solar system Proton capture the p-nuclei Photon-disintegration reactions involved in the astrophysical p-process: (γ,n), (γ,p) & (γ,α) Nucleonsynthesis of the 35 stable p-rich nuclei, which cannot be reached in normal Neutron capture process Photon-disintegration: p-process (,n) Experiments to improve knowledge on α-nuclear potentials for astrophysical applications + () D. Galaviz Redondo, Centro de Física Nuclear da Universidade de Lisboa

  25. Production & study ofp-nuclei Radiative α-capture reactions (α,p), (α,n) & (α ,γ) on proton-rich nuclei Optimum energy for CMAM Astrophysical energy region Gamow-peak 6-12 MeV Au-Mo-Au γ p α-beam Eα = 5-15 MeV Iα= 1µA n γ α Si-detector 197Au(a,n)200Tl α-Intensity: 197Au(α,α)197Au 197Au(α,γ) reactions D. Galaviz Redondo, Centro de Física Nuclear da Universidad de Lisboa

  26. 10 h after end of activation T1/2 (Tl) = 25.84 +/-0.24 h D. Galaviz Redondo, Centro de Física Nuclear da Universidad de Lisboa O. Tengblad: CMAM 10 year’s anniversary March 2013

  27. Nuclear Physics Beam Line Formation of 12C and 7Be Break-up Study of following the reactions 10B(3He,p)12C* & 11B(3He,d)12C* Cross section Study of 3He(4He,g)7Be R&D for future detectors Monolithic Si -telescope Phoswich – Scintillator telescope O. Tengblad: CMAM 10 year’s anniversary March 2013

  28. Detectors: DSSSD  monolithic Si telescope DSSSD + PAD Monolithic DE 1 mm + E 500 mm DE 40 mm + E 500 mm 5x5 cm2 16x16 strips á 3mm 256 pixel detectors á 3x3=9 mm2 32 electronic channels Detector area: 5x5 cm2 64 pixel detectores á 3x3=9 mm2 128 electronic channels Solid angle 20% of the DSSSD and 4 times more electronics needed!! O. Tengblad: CMAM 10 year’s anniversary March 2013

  29. Monolithic DE-E telescope DE 1 mm + E 500 mm DE (N+) E detector (N-) 1 mm N+ Detector DE 500 mm N- Detector E Front cathode 0.5 µm Rear cathode 0.5 mm O. Tengblad: CMAM 10 year’s anniversary March 2013

  30. monolithic Si telescope @ CMAM E FWHM 80 KeV DE Rutherford Scattering 27Al Beams of 27Al & 23Na @ CMAM green  30 MeVblue  25 MeVred  20 MeVyellow  15 MeVdark blue  10 MeV 23Na O. Tengblad: CMAM 10 year’s anniversary March 2013

  31. “Gamma beam” test bench beam: protones de 1 MeV target: teflon 19F(p,αg)16O O. Tengblad: CMAM 10 year’s anniversary March 2013

  32. LaBr3 LaCl3 D E1 D E2 E 30 50 mm Phoswich for high Energy Gamma and Proton detection • Two crystals of different materials with one unique readout?  Optically compatible O. Tengblad: CMAM 10 year’s anniversary March 2013

  33. PHOSWICH RESPONSE TO 60Co 60Co 60Co 60Co FWHM 2.9% LaBr3 LaCl3 60Co LaCl3 FWHM 3.4% Nº cuentas Nº cuentas LaBr3 Energía (canal) Energía (canal) O. Tengblad: CMAM 10 year’s anniversary March 2013

  34. Phoswich: 1st results  it works Tengblad et.al. Nucl. Instr. and Meth. A704 , 19-26, (2013 ) + FWHM 4 % ENERGY SPECTRUM WITH GATE B PHOSWICH TEMPORAL SPECTRUM O. Tengblad: CMAM 10 year’s anniversary March 2013

  35. Future Reactions studies @ CMAM Difficult to compare previous results Uncertainties associated to thickness and composition of the target } 170(p, γ)18F 170(p, α)14N expeiments in inversekinematics p(170,18F)g p(170,14N)α LaBr3+LaCl3 Phoswich 9x { 15x15 mm2 x (40+60)mm } crystals 3-1% resolution, 40% photopeak efficiency 0-20 MeV ISOLDE/JYFL Si-Ball: 36x4 quadrants of 1 mm Si L.M. Fraile & J.Äystö, NIMA513 (2003) 28 O. Tengblad: CMAM 10 year’s anniversary March 2013

  36. Summary The Nuclear Physcis Line at CMAM is operational since 2005 I have shown that there are still some reactions especially of Astrophysical interest that can be performed at a 5 MV accelerator Our experimental activity has given rise to 2 thesis, 6 articles in Peer Reviewed Journals, and various conference contributions Further we have been using the accelerator for R&D activity for our experiments at international nuclear physics facilities around the world O. Tengblad: CMAM 10 year’s anniversary March 2013

  37. Collaborators • M. Alcorta, A. Becerril, M.J.G. Borge, J.A. Bris, M. Carmona-Gallardo, • M. Cubero, E. Nacher, M. Madurga, A. Perea, D. Galaviz Redondo, • J. Sanchez del Rio, O. Tengblad, • Instituto Estructura de la Materia, CSIC, Madrid, Spain • H.O.U. Fynbo, O. Kirsebom, S. Hyldegaard, K. Riisager • Department of Physics and Astronomy, Århus University, Denmark • B. Jonson, T. Nilsson, G. Nyman • Fundamental Physics, Chalmers Univ. of Technology, Göteborg,Sweden • N.S. Bondili, B. R. Fulton, C. Aa Diget • University of York, United Kingdom. • M. Hass, V. Kumar & G. Haquin, Y. Nir-El, Z. Yungreis • the Weizmann inst & Soreq Research Center, Yavne, Israel • A. Muños Martín, A. Maira Vidal • Centro de Micro Analisis de Materiales, UAM, Madrid, Spain O. Tengblad: CMAM 10 year’s anniversary March 2013

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