Study of two neutron transfer reaction and resonant

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Study of two neutron transfer reaction and resonant elastic scattering induced by 11 Li,

Study of two neutron transfer reaction and resonant elastic scattering induced by 11 Li, with the MAYA active target. Seminar ISOLDE 06/10/10 -1 -

Outline 1. MAYA@TRIUMF : Transfer & resonant reactions with 11 Li - Motivations -

Outline 1. [email protected] : Transfer & resonant reactions with 11 Li - Motivations - The active target MAYA - The TRIUMF experiment 2. [email protected] : Possible experiments - Technical issues - Possibilities Seminar ISOLDE 06/10/10 -2 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE • Halo occurrence condition(s) low binding energy low

Motivations Experimental setup Results Conclusion [email protected] • Halo occurrence condition(s) low binding energy low angular momentum (1) • N=7 parity inversion 10 Li (G. S. ) : s-state (2) s-p mixing in 11 Li (3) • 11 Li coulomb dissociation strong correlations K. Riisager et al. , Nucl. Phys. A 548, 393 (1992) H. Simon et. al. , Nucl. Phys. A 791, 267 (2007) (3) H. Simon et. al. , Phys. Rev. Lett. 83, 496 (1999) (4) T. Nakamura et. al. , Phys. Rev. Lett. 96, 252502 (2006) (1) (2) Seminar ISOLDE 06/10/10 -3 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Study of “low energy” reactions induced by 11

Motivations Experimental setup Results Conclusion [email protected] Study of “low energy” reactions induced by 11 Li on a proton target - 2 neutron transfer reaction. angular distribution : strength of the correlation - 1 neutron transfer reaction. angular distribution : spectroscopy of the halo. - Elastic scattering. angular distribution : density distribution Reactions with losely bound nucleus at low energy - Resonant elastic scattering. excitation function : 12 Li Isobaric Analog States Couplings! N. Keeley and V. Lapoux, Phys. Rev. Lett. 77, 014605 (2008) A. Lemasson et al. , accepted in Phys Rev. C Seminar ISOLDE 06/10/10 -4 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Study of “low energy” reactions induced by 11

Motivations Experimental setup Results Conclusion [email protected] Study of “low energy” reactions induced by 11 Li on a proton target - 2 neutron transfer reaction. angular distribution : strength of the correlation - 1 neutron transfer reaction. angular distribution : spectroscopy of the halo. Good angular coverage - Elastic scattering. angular distribution : density distribution - Resonant elastic scattering. excitation function : 12 Li Isobaric Analog States + Thick target Active target (detection/ reaction ) Seminar ISOLDE 06/10/10 -5 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE ISAC II up to 5000 pps 11 Li

Motivations Experimental setup Results Conclusion [email protected] ISAC II up to 5000 pps 11 Li @ 5 A Me. V 0° beamline with PPAC detector and the active target MAYA Seminar ISOLDE 06/10/10 -6 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE C. E. Demonchy et al. , Nucl. Instrum.

Motivations Experimental setup Results Conclusion [email protected] C. E. Demonchy et al. , Nucl. Instrum. Methods A 573, 145 (2007) Seminar ISOLDE 06/10/10 -7 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE A two dimensional charge – one dimensional time

Motivations Experimental setup Results Conclusion [email protected] A two dimensional charge – one dimensional time projection chamber Cathode recorded pattern 2 dimensions Wire recorded time 3 rd dimension Seminar ISOLDE 06/10/10 -8 -

Motivations Experimental setup Results Light particles + high energy Si / Cs. I 2

Motivations Experimental setup Results Light particles + high energy Si / Cs. I 2 solid identification stages + 1 gaseous stage Conclusion [email protected] Medium energy PADS / Si Large identification dynamics! Seminar ISOLDE 06/10/10 -9 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Charge distribution : “ The recorded charge distribution

Motivations Experimental setup Results Conclusion [email protected] Charge distribution : “ The recorded charge distribution is the result of the convolution of the charge distribution created by a point-source and the hexagonal geometry of the pads, all along the charged particles tracks and weighted by their energy losses. ” YMAYA (mm) A simulation is necessary to develop the reconstruction algorithms and to estimate the geometric efficiency 160 80 0 90 180 Seminar ISOLDE 06/10/10 Depth (mm) - 10 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Two experiments – Two setups “Thin” target :

Motivations Experimental setup Results Conclusion [email protected] Two experiments – Two setups “Thin” target : fixed energy “Thick” target : fixed c. m. angle (670 mbar – 7. 6 mg/cm 2) (150 mbar - 1. 7 mg/cm 2) excitation functions angular distributions angle-angle correlations energy-energy correlations Seminar ISOLDE 06/10/10 - 11 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Mass measurement by Q-value measurement : 1 H(11

Motivations Experimental setup Results Conclusion [email protected] Mass measurement by Q-value measurement : 1 H(11 Li, 9 Li)t corrélations énergie-énergie corrélations angle-angle S 2 n (11 Li) = 363(22) ke. V T. Roger et al. , Phys. Rev. C 79, 031603(R) (2009) Can be extended to unbound nuclei Seminar ISOLDE 06/10/10 - 12 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Angular distribution @ 4. 3 A Me. V

Motivations Experimental setup Results Conclusion [email protected] Angular distribution @ 4. 3 A Me. V - Very close to Rutherford unusual behavior (qgrazing = 10°) - Global Optical Potentials : Fail! Need to increase Wd et diminish awd Surface peaked absorption! (breakup + transfer, compound nucleus) Seminar ISOLDE 06/10/10 - 13 -

Motivations Experimental setup Results Conclusion 3 A Me. V MAYA@ISOLDE 4. 3 A Me.

Motivations Experimental setup Results Conclusion 3 A Me. V [email protected] 4. 3 A Me. V transitions to 9 Li (GS) & 9 Li* (2. 69 Me. V) DWBA/CRC calculation required Seminar ISOLDE 06/10/10 - 14 -

Motivations Experimental setup Results Conclusion CCBA calculations (I. J. Thompson) 11 Li: s 2

Motivations Experimental setup Results Conclusion CCBA calculations (I. J. Thompson) 11 Li: s 2 & p 2 10 Li [email protected] E 11 G. S. Rm rms (s 1/2)2 wt (p 1/2)2 wt (Me. V) (fm) (%) p sequential P 0 -0. 33 3. 05 3 94 s P 2 -0. 32 3. 39 31 64 P 3 0. 33 3. 64 45 51 simultaneous 9 Li (g. s. ) I. J. Thompson et al. (Phys. Rev. C 49, 1904 (1994)) 3 A Me. V 4. 3 A Me. V I. Tanihata et al. , Phys. Rev. Lett. 100, 192502 (2008) Configuration mixing! Seminar ISOLDE 06/10/10 - 15 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Angular distribution @ 4. 3 A Me. V

Motivations Experimental setup Results Conclusion [email protected] Angular distribution @ 4. 3 A Me. V (integrated over 10 Li states) Contribution of 9 Li(cont. ) (minor) Hard to identify the populated CRC state calculation needed! Seminar ISOLDE 06/10/10 - 16 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Kinematics reconstruction with the energy/energy (range) correlations VERTEX

Motivations Experimental setup Results Conclusion [email protected] Kinematics reconstruction with the energy/energy (range) correlations VERTEX TOTAL PATH BEAM HEAVY VERTEX TOTAL PATH Seminar ISOLDE 06/10/10 - 17 -

Motivations Experimental setup Results Conclusion 150° cm MAYA@ISOLDE 175° cm Resonance @ Ecm ≈

Motivations Experimental setup Results Conclusion 150° cm [email protected] 175° cm Resonance @ Ecm ≈ 3 Me. V Possible IAS of 12 Li (T=3 state observed in 12 Be: Charity et al. ) R. J. Charity et al. , Phys. Rev. C 76, 064313 (2007) R matrix calculation to assign a spin Seminar ISOLDE 06/10/10 - 18 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE R-Matrix calculations • E < 2 Me. V

Motivations Experimental setup Results Conclusion [email protected] R-Matrix calculations • E < 2 Me. V Rutherford • Hard sphere phase shifts Cross section too high 1 level approximation not valid Complex phase shifts VB 11 Li+p optical potential needed! All the processes are interconnected! Seminar ISOLDE 06/10/10 - 19 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Breit Wigner fit: Incoherent sum of Coulomb et

Motivations Experimental setup Results Conclusion [email protected] Breit Wigner fit: Incoherent sum of Coulomb et BW Er = 3. 0 Me. V Gtot = 1. 1 Me. V Seminar ISOLDE 06/10/10 - 20 -

Motivations Experimental setup Our result: Results Conclusion MAYA@ISOLDE Y. Aksyutina : s state @

Motivations Experimental setup Our result: Results Conclusion [email protected] Y. Aksyutina : s state @ 1. 5 Me. V Er = 3. 0 Me. V Gtot = 1. 1 Me. V Y. Aksyutina et al. , Phys. Lett. B 666, 430 (2008) Gsp @ 3 Me. V: l = 0 : 7. 58 Me. V No positive parity states l = 1 : 5. 28 Me. V below 6. 5 Me. V (E*=3. 5 Me. V) l = 2 : 1. 91 Me. V + B. A. Brown, Private Communication s state with S = 0. 14 = d state with S = 0. 57 d state compatible with CXMSM calculations (Z. X Xu et al. submitted to Phys. Rev. C) Seminar ISOLDE 06/10/10 - 21 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE + Elastic scattering angular distribution. ≈ Rutherford up

Motivations Experimental setup Results Conclusion [email protected] + Elastic scattering angular distribution. ≈ Rutherford up to 90° cm: coupling to transfer and breakup channels + 1 n and 2 n transfer angular distributions @ 3 A and 4. 3 A Me. V First calculations indicate a strong correlation between the halo-neutrons + Mass of 11 Li by Q-value measurement + 11 Li(p, p)11 Li excitation function at 150° and 175° cm possible T=3 state in 12 Be Interconnected processes! Need global treatment with CRC & CDCC Complete study - ideal study with active targets - ideal case for Coupled Reaction Channel calculations Seminar ISOLDE 06/10/10 - 22 -

MAYA@TRIUMF Collaborators T. Roger , H. Savajols, M. Caamaño, P. Roussel-Chomaz GANIL, Bd Henri

[email protected] Collaborators T. Roger , H. Savajols, M. Caamaño, P. Roussel-Chomaz GANIL, Bd Henri Becquerel, BP 55027, 14076 Caen Cedex 05, France W. Mittig and H. Wang NSCL, MSU, East Lansing, MI 48824 -1321, USA I. Tanihata, M. Alcorta, D. Bandyopadhyay, R. Bieri, L. Buchmann, B. Davids, N. Galinski, D. Howell, W. Mills, R. Openshaw, E. Padilla-Rodal, G. Ruprecht, G. Sheffer, A. C. Shotter, M. Subramanian, M. Trinczek, and P. Walden TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V 6 T 2 A 3, Canada R. Kanungo and A. Gallant Saint Mary’s University, 923 Robie St. , Halifax, Nova Scotia B 3 H 3 C 3, Canada M. Notani and G. Savard ANL, 9700 S. Cass Ave. , Argonne, IL 60439, USA I. J. Thompson LLNL, L-414, P. O. Box 808, Livermore CA 94551, USA ++ MAYA’s Technical Staff as : J. F. Libin, P. Gangnant, C. Spitaels, L. Olivier & G. Lebertre Seminar ISOLDE 06/10/10 - 23 -

MAYA@ISOLDE: possible experiments Seminar ISOLDE 06/10/10 - 24 -

[email protected]: possible experiments Seminar ISOLDE 06/10/10 - 24 -

Motivations Experimental setup Results - MAYA: slow gazeous detector Conclusion MAYA@ISOLDE Pile-up above 1

Motivations Experimental setup Results - MAYA: slow gazeous detector Conclusion [email protected] Pile-up above 1 ion/10 µs - MAYA dynamics from p(11 Li, 9 Li)t @ 4. 3 A Me. V – 150 mbar C 4 H 10 CM = 35° E 9 Li = 53. 9 Me. V Et = 1. 4 Me. V <d. E/dx>9 Li = 26 ke. V/mm CM = 145° E 9 Li = 19. 1 Me. V Et = 36. 3 Me. V <d. E/dx>t = 1. 5 ke. V/mm Dynamics ≈ 20 Upgrade of GASSIPEX : threshold 100 m. V 30 m. V Seminar ISOLDE 06/10/10 - 25 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Possible solution : mask the beam Transparency tunable

Motivations Experimental setup Results Conclusion [email protected] Possible solution : mask the beam Transparency tunable (0 – 10%) Artificially increases the dynamics E. Kahn, J. Gibelin E 548 a (GANIL): 68 Ni(d, d’) dynamics ≈ 100 Seminar ISOLDE 06/10/10 - 26 -

Motivations Experimental setup Results Conclusion MAYA@ISOLDE Pulsed beam from EBIS : Instantaneous maximum intensity!

Motivations Experimental setup Results Conclusion [email protected] Pulsed beam from EBIS : Instantaneous maximum intensity! if Ipps>103 : on 1 µs Imax ≈ 103 Ipps If the beam track is needed: (resonant reaction, precise transfer reactions) limited to 102 – 103 pps Else: theoretically no restriction BUT: 132 Sn beam @ 105 pps into 150 mbar C 4 H 10 : 1. 7 x 107 e- /mm/1µs Very close to the sparking limit… Seminar ISOLDE 06/10/10 - 27 -