Nuclear Physics CMAM Olof TENGBLAD IEM CSIC O
Nuclear Physics @ CMAM Olof TENGBLAD IEM - CSIC O. Tengblad: CMAM 10 year’s anniversary March 2013 1
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 O. Tengblad: CMAM 10 year’s anniversary March 2013 2
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. 12 C & The triple alpha process 4 He + 4 He ↔ 8 Be + 4 He ↔ 12 C + γ + 7. 367 Me. V clustering O. Tengblad: CMAM 10 year’s anniversary March 2013 3
12 C - The Cosmic Connection 1953 1957 1958 1966 O. Tengblad: CMAM 10 year’s anniversary March 2013 4
Morinaga’s Idea for rotational bands in n nuclei O. Tengblad: CMAM 10 year’s anniversary March 2013 5
12 C 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 6
The Triple Alpha Process Q/k. T r 3 Grad e- Revised rates for the stellar triple-�process from new measurement of 12 C resonances Fynbo et. al. Nature 433 (2005) 136 -139 (IF: 29, 273) O. Tengblad: CMAM 10 year’s anniversary March 2013 7
How to produce the 12 C* States @ CMAM 9 B* A+a 3 He C* @ 4. 9 Me. V B*+b p + 10 B 13 N* 12 C* OR 3 He @ 8. 5 Me. V + 11 B O. Tengblad: CMAM 10 year’s anniversary March 2013 d + 12 C* 8
Waggoner et al. , NPA 88(1966)81 3 He (@ 2, 45 Me. V) + 10 B p E O. Tengblad: CMAM 10 year’s anniversary March 2013 Ep 9
Can we do it better today? § Detection system u 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 Monte. Carlo simulations including both theory and the actual set-up makes possible to extract information about decay mode, branching ratios and other physics parameters. O. Tengblad: CMAM 10 year’s anniversary March 2013 back strips 1 4 3 2 1 2 3 4 front strips 50 x 50 mm 2 16 front x 16 back strips 3 x 50 mm 2 10
Reaction Studies 3 He 11 B(3 He, d) 10 B(3 He, p) @ 4. 9 and 8. 5 Me. V Targets: 18. 9 mg/cm 2 10 B 4 mg/cm 2 C-backing 22. 0 mg/cm 2 11 B 4 mg/cm 2 C-backing O. Tengblad: CMAM 10 year’s anniversary March 2013 = 38% of 4 11
Particle Identification 3 He + 11 B d+ Reaction products 12 C* Q-Value (Me. V) 14 N + 20. 74 13 C +p 13. 19 12 C +d 10. 46 10 B + 9. 12 12 C +n+p 8. 24 6 Li + 2 4. 66 9 Be +p+ 2. 54 5 He + p + 2 0. 07 11 B + 3 He 0. 00 11 C +t -2. 00 d p O. Tengblad: CMAM 10 year’s anniversary March 2013 DE 12
p + �+ �+ a coincidences � Excitation Energy in 12 C reconstructed Esum=3/2*E 1+0. 092 Me. V E 12 C (Me. V) SE 12 C* 1 8 Be(0+) 2 3 Ei( ) (Me. V) We can deduce the partial branching ratios for each level in 12 C* via the 0+ and 2+ states in 8 Be O. Tengblad: CMAM 10 year’s anniversary March 2013 13
3 He+10 B p+3 punchthroughs 3 He+11 B d+3 n+p+3 12 C excitation Summing 3 -decay of the T=1 level @ 15. 11 Me. V 12 C excitation energy from proton O. Tengblad: CMAM 10 year’s anniversary March 2013 14
Indirect Detection of -decay 3 He @ 4. 5 Me. V 15. 11 12. 71 1+ 1+ 11. 83 2 - ≈10 0+ p 10 B 17 mg/cm 2 (+3 mg/cm 2) • The proton gives initial populated resonance in 12 C • This state can emit and populate a lower excited state • The 3 alphas give resonance populated in 12 C after -decay 12 C* 7. 65 12 C 0+ O. Tengblad: CMAM 10 year’s anniversary March 2013 15
-decay of the T=1 level @ 15. 11 Me. V M. Alcorta et. al. Phys. Rev. C 86, 064306 , (2012) M. Alcorta et al, NIM A 605, 318 -325 (2009) O. S. Kirsebom et al, Phys. Lett B 680, 44 -49 (2009) O. Tengblad: CMAM 10 year’s anniversary March 2013 15. 11 1+ 12. 71 1+ 11. 83 2 - ≈10 0+ 7. 65 0+ 12 C Thesis de Martin Alcorta 2010 16
Summary: what have we learned 15. 11 1+ 14. 08 4+ 13. 35 (2 -) 15. 11 1+ E, G 14. 08 4+ E, G 13. 35 4 - 4 - 12. 71 1+ 11. 83 2 - E, G 10. 84 1 - E, G ≈10 (0, 2+) 9. 64 3 - 7. 65 0+ 4. 44 g. s. G 11. 83 211. 1/11. 2 0+, 2+ 10. 84 19. 64 3 - 7. 65 0+ 2+ 4. 44 2+ 0+ g. s. 0+ 12 C O. Tengblad: CMAM 10 year’s anniversary March 2013 1. Observation of -decay and -decay of T=1 15. 11 Me. V state 2. -decay of T=0 12. 71 Me. V state observed to Hoyle state and to the broad 10 Me. V state 3. Improved measurements of energy and widths for known states 4. Branching ratios of decay through the 8 Be(gs) were measured for natural parity states 5. Studied the decay mechanism of the 12. 71 Me. V resonance using Dalitz plots 6. Dalitz plots used to determine Jp of 13. 35 Me. V resonance Thesis de Martin Alcorta 2010 17
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 O. Tengblad: CMAM 10 year’s anniversary March 2013 18
Motivation for the 3 He(4 He, γ)7 Be cross section measurement 1. 3 He(4 He, γ)7 Be → source of uncertainty in determining the high energy solar neutrino flux from the reaction 7 Be(p, γ)8 B 2. The reaction plays an important role in the 7 Li abundance 3. Available data on the astrophysical S factor shows a significant scatter and persistent discrepancy → 0. 53(5) ke. V b used in SSM and 0. 54(9) ke. V b used SBBN for S 34(0) O. Tengblad: CMAM 10 year’s anniversary March 2013 19
Possible experiment 3 He(4 He, γ)7 Be b) Activity- 478 ke. V : 7 Be decays to 7 Li BR=10. 45 (4) % T 1/2=53. 29 (7) days Simple setup a) Prompt- : DC 429, 429 0 Complicated Setup O. Tengblad: CMAM 10 year’s anniversary March 2013 20
Experimental set-up at CMAM Np by charge integration Nt by energy loss 4 He 3 He 7 Be Target: respectivley Delayed Scattering foil: 1 mm thick Ni foil Gamma Nt=9. 966 · 1018· l·P/(T+T 0) Np by 3 4 Beam: He respectively He Monitoring measurement + Energy: 4 Me. V 1 O. Tengblad: CMAM 10 year’s anniversary March 2013 21
3 He(4 He, g)7 Be cross section study by induced g� radiation Thesis Mariano Carmona Gallardo 2013 • ~900 cts. in 478 peak. • 6 days of counting M. Carmona-Gallardo, et. al. Phys. Rev. C 86, 032801, (2012) O. Tengblad: CMAM 10 year’s anniversary March 2013 22
Nuclear Physics Beam Line Life of stars Formation of 12 C and 7 Be Study of 10 B(3 He, p)12 C* & 11 B(3 He, d)12 C* Study of 4 He(3 He, g)7 Be & 3 He(4 He, g)7 Be Death of stars D. Galaviz Redondo, Centro de Física Nuclear da Universidade de Lisboa Production of p-nuclei 197 Au(a, n)200 Tl reaction cross section R&D O. Tengblad: CMAM 10 year’s anniversary March 2013 23
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) Photon-disintegration: p-process + ( ) Nucleonsynthesis of the 35 stable p-rich nuclei, which cannot be reached in normal Neutron capture process ( , n) Experiments to improve knowledge on α-nuclear potentials for astrophysical applications D. Galaviz Redondo, Centro de Física Nuclear da Universidade de Lisboa 24
Optimum energy for CMAM Astrophysical energy region Gamow-peak 6 -12 Me. V Radiative α-capture reactions (α, p), (α, n) & (α , γ) on proton-rich nuclei Au-Mo-Au γ α-beam Eα = 5 -15 Me. V Iα= 1µA α γ p n 197 Au( , n)200 Tl Si-detector α-Intensity: 197 Au(α, α)197 Au(α, γ) reactions D. Galaviz Redondo, Centro de Física Nuclear da Universidad de Lisboa 25
10 h after end of activation T 1/2 (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 26
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 Monolithic Si -telescope Phoswich – Scintillator telescope O. Tengblad: CMAM 10 year’s anniversary March 2013 27
Detectors: DSSSD monolithic Si telescope DSSSD + PAD Monolithic DE 1 mm + E 500 mm DE 40 mm + E 500 mm 5 x 5 cm 2 16 x 16 strips á 3 mm Detector area: 5 x 5 cm 2 256 pixel detectors á 3 x 3=9 mm 2 64 pixel detectores á 3 x 3=9 mm 2 128 electronic channels 32 electronic channels Solid angle 20% of the DSSSD and 4 times more electronics needed!! O. Tengblad: CMAM 10 year’s anniversary March 2013 28
Monolithic DE-E telescope DE 1 mm + E 500 mm DE (N+) E detector (N-) 1 mm N+ Detector DE Front cathode 0. 5 µm O. Tengblad: CMAM 10 year’s anniversary March 2013 500 mm NDetector E Rear cathode 0. 5 mm 29
monolithic Si telescope @ CMAM Rutherford Scattering DE E FWHM 80 Ke. V 27 Al Beams of 27 Al & 23 Na @ CMAM green 30 Me. V blue 25 Me. V red 20 Me. V yellow 15 Me. V dark blue 10 Me. V O. Tengblad: CMAM 10 year’s anniversary March 2013 23 Na 30
“Gamma beam” test bench beam: protones de 1 Me. V target: teflon 19 F(p, α )16 O O. Tengblad: CMAM 10 year’s anniversary March 2013 31
p Phoswich for high Energy Gamma and Proton dete Two crystals of different materials with one unique readout? Optically compatible La. Br 3 La. Cl 3 D E 1 E 30 Materials D E 2 50 mm Energy Light yield Resolution (photons/ (at 662 ke. V γ) ke. V) (%) Decay time (ns) λemision La. Br 3 2. 9 63 16 380 nm La. Cl 3 3. 8 49 28 350 nm O. Tengblad: CMAM 10 year’s anniversary March 2013 32
PHOSWICH RESPONSE TO 60 Co Nº cuentas La. Cl 3 FWHM 3. 4% Nº cuentas 60 Co FWHM 2. 9% La. Br 3 La. Cl 3 La. Br 3 Energía (canal) O. Tengblad: CMAM 10 year’s anniversary March 2013 Energía (canal) 33
Phoswich: 1 st results it works Tengblad et. al. Nucl. Instr. and Meth. A 704 , 19 -26, (2013 ) FWHM 4 % + ENERGY SPECTRUM WITH GATE B PHOSWICH TEMPORAL SPECTRUM O. Tengblad: CMAM 10 year’s anniversary March 2013 34
Future Reactions studies @ CMAM 170(p, γ)18 F 170(p, α)14 N } Difficult to compare previous results Uncertainties associated to thickness and composition of the target expeiments in inverse kinematics 17 18 p( 0, F) p(170, 14 N)α ISOLDE/JYFL Si-Ball: 36 x 4 quadrants of 1 mm Si L. M. Fraile & J. Äystö, NIMA 513 (2003) 28 La. Br 3+La. Cl 3 Phoswich 9 x { 15 x 15 mm 2 x (40+60)mm } crystals 3 -1% resolution, 40% photopeak efficiency 0 -20 Me. V O. Tengblad: CMAM 10 year’s anniversary March 2013 35
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 36
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 37
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