ALTO scientific program toward SPIRAL2

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1 ALTO scientific program toward SPIRAL2 David Verney IPN Orsay RIB availability, intensity and purity R&D RIB developments Instrumentation and detectors : already available, under development, projects Physics : Proposals and LoI received so far by the ALTO PAC

2 Tandem building Institut de Physique Nucléaire Campus of the Paris Sud University Orsay (France) Page 2/

3 March 2012 green light from French nuclear safety authorities May 13 th 2013 formal inauguration May th nd Workshop on the Physics at ALTO Page 3/

4 Tandem/ALTO general layout Stable beams line 320 BACCHUS line 410 ISOL Driver Line 210 SPLIT POLE ISOL Production cave ISOL Mass separator and Low energy RIB lines line 420 ORGAM (MINIBALL 2014) cluster/ molecular/ droplets beams Radioactive beam lines Stable beam without spectrometer Stable beam with spectrometer Page 4/

5 ALTO=ISOL installation based on photo-fission: the first of its kind in the world e-linac 10 µa 50MeV (former 1 st section of the LEP injector) BEDO beta decay spectroscopy secondary beam lines POLAREX nuclear orientation on line TIS vault ~5.10^11 fissions/s PARRNe mass separator Target Ion-source ensemble kicker - bender identification station Page 5/

6 ALTO=ISOL installation based on photo-fission: the first of its kind in the world Measured productions yields at the detection point on line with the PARRNe mass separator electrons -> gamma induced fission nominal intensity: Production pps /10 µa e- 10 μa ~ fissions/s Stable Systematic yield measurements made in June 2006 Hot plasma ion source 100 na electrons 50 MeV Page 6/

7 Beam diversity at ALTO The variety of the physics program at ALTO strongly depends on RIB availability, intensity and purity Semi refractory Lanthanide Region (slow release from UCx) refractory Semi refractory o C Ni Cu point de fusion point d'ebullition Ge Ga Ni Sr Cu Zn Ge As RbSr Zn Ga AsSeBr Br Kr Rb Y Zr Nb Mo Tc Ru Rh Nb Mo Y Zr Tc Ru Rh Pd LaCePr NdPm Sn Ag In Pd Sb Sm Eu Ag Cd In Sn Sb Te Cd La Ce PrNdPmSm CsBa Eu Te I Xe CsBa Z65 An ambitious scientific program at ALTO toward SPIRAL2 goes hand in hand with an ambitious R&D program for RIB developments in a European ISOLDE-SPES-SPIRAL2 context Page 7/

8 Low energy radioactive ion beam lines The variety of the physics program at ALTO strongly depends on available LERIB lines and their instrumentation PARRNe mass separator room (formerly line 110 of the Tandem) Max number of measurement positions : 6 PARRNe mass separator Identification station (existing) POLAREX TETRA New line: 2014 project TAS project BEDO/TETRA (existing) SPECOLOR project Page 8/

9 Separator room : present configuration new tape station : BEDO PARRNe mass separator kicker-bender PARRNe mass separator focal plane Page 9/

10 A hint on RIB developments at ALTO Recent progress and short term perspective

11 RIB developments at ALTO R&D program on the fluorination of Lanthanides Lanthanide Region o C Ni Cu point de fusion point d'ebullition Ge Ga Ni Sr Cu Zn Ge As RbSr Zn Ga AsSeBr Br Kr Rb Y Zr Nb Mo Tc Ru Rh Nb Mo Y Zr Tc Ru Rh Semi refractory (slow release from UCx) Pd LaCePr NdPm Sn Ag In Pd Sb Sm Eu Ag Cd In Sn Sb Te Cd La Ce PrNdPmSm CsBa Eu Te I Xe CsBa Z65 Strong physics motivation: study of mid-shell effects B(E2) measurements fast timing Program led by B. Roussière (IPN Orsay), collaboration CSNSM (France), Tandar (Argentina) and INRNE (Bulgaria) first fast-timing experiment at ALTO with low-intensity e - beam on 137,139 Cs Eur. Phys. J. A (2011) 47: 106 Page 11/

12 RIB developments at ALTO R&D program on the fluorination of Lanthanides IPN Chemists, engineers and physicists N. Barré-Boscher, M. Cheikh Mhamed, S. Essabaa, C. Lau, B. Roussière, A. Said, S. Tusseau-Nenez SIHL off-line mass separator Strategy : Fasten the release of Ln by formation of LnF n + molecular beams Tests : the different parameters: injected fluoride gas target temperature source type Target made of Lanthanide oxides mixed in graphite powder

13 RIB developments at ALTO R&D program on the fluorination of Lanthanides Mass scan CF4 inlet tube flow max compatible with good running conditions:~6 x 10-3 bar.l/s La Pr Measurements performed with hot plasma (Febiad) and surface (W) ion sources Eu Ho High correlation between the valence of the Ln and the observed ions (Ln +, LnF + or LnF 2 + ). Reliable T control 1 st on-line experiment 2014 (before summer) fast timing measurements Page 13/

14 RIB developments and R&D in ISOL science UCx developments at IPN - ALTO ENSAR JRA02, ActILab: Actinide ISOL Target R&D Laboratory CERN-ISOLDE GANIL-SPIRAL2 INFN- SPES IPN- ALTO Laboratory of Chemical Sciences, Univ. of Rennes (France) for the synthesis of samples and microstructural characterizations (SEM) ICMMO-Orsay for SEM observations and XRD measurements on non-radioactive samples Objectives: Today : ALTO, fissions / sec Tomorrow : SPIRAL2 >10 13 fissions / sec Future : EURISOL, fissions / sec Nowadays The most widely used ISOL targets = uranium carbide + graphite (UCX), mostly UC2 Concentration of 238 U ~ 3 g/cm3 Operate at temperatures ranging from C to C How to increase the RIB intensities? Increasing the primary beam Increasing uranium density higher production rate of FPs IPN Chemists, engineers and physicists N. Barré-Boscher, M. Cheikh Mhamed, E. Cottereau, S. Essabaa, C. Lau, B. Roussière, A. Said, S. Tusseau-Nenez BUT that cannot be the end of the story: favor the FPs releases, particularly crucial for the short-lived species Controlling the porosity Reducing the thickness of pellets Page 14/

15 RIB developments and R&D in ISOL science UCx developments at IPN - ALTO Carburation lab SIHL off-line mass separator 15 MV MP Tandem Strategy : Measure the release properties of pellets after irradiation Control and characterize : the different parameters: UCx synthesis method porosity microstructure physicochemical properties Densest samples Porous samples Page 15/

16 RIB developments and R&D in ISOL science UCx developments at IPN - ALTO Deuteron Tandem beam Irradiation time 20 min Cooling time 30 min Heating 1700 C during 30 min Secondary vacuum Cooling to 70 C in 10 min The furnace for heating test is home made. Calibration by melting of Pt More on the method in: B. Hy et al., NIM B 288 (2012) 34 Page 16/

17 RIB developments and R&D in ISOL science UCx developments at IPN - ALTO Results from gamma spectrometry Clearly, diffusion and effusion are correlated with the porosity / pore size distribution of the sample Nano tubes Originally proposed by Lisa Biasetto et al. INFN Page 17/

18 Log Differential Intrusion (ml/g) Differential Intrusion (ml/g/µm) Log Differential Intrusion (ml/g) Differential Intrusion (ml/g/µm) He pycnometry PARRNe : r eff = 8.1 g.cm -3 P open = 32 % SEM observations Cracks on surface Hg porosimetry UC 2 graphite 0,14 0,12 0,1 0,08 0,06 0,04 0, Cracks ,25 0,2 0,15 0,1 0,05 1 Pore diameter (µm) 0 1 Porosity near UC 2 aggregats Porosity near graphite 0,1 0,1 Pore diameter (µm) 0,01 0,01 0,001 CNT : r eff = 8.5 g.cm -3 P open = 59 % UC 2 Network of CNT + UC 2 UC 2 is growing on CNT 1,2 1 0,8 0,6 0,4 0,2 Porosity near UC 2 aggregats 3,5 3 2,5 2 1,5 1 0,5 0 1 Porosity near CNT 0,1 Pore diameter (µm) 0,01 0,001 Release measurements : ,1 Pore diameter (µm) 0,01 First on-line measurement yields from a novel ACTILAB conceived UC(nano) target at ALTO First trimester ,001

19 RIB developments and R&D in ISOL science Laser ionized RIBs at ALTO The ALTO laser ion source RIALTO (Resonant Ionization at ALTO) Installation supervised by S. Franchoo with the help of R. Li, D. Yordanov (from 1/10/13) with the collaboration of ISOLDE: V. Fedosseev, B. Marsh, T. Goodacre Univ. Manchester: K. Flanagan Univ. Mainz: T. Kron, K. Wendt Mezzanine of the mass separator/rib zone The on-line laser installation validated in 2011 with the production of Ga beams. 2012: Upgrade 2 new lasers (Radiant Dyes). 2013: Reference cell (in progress...) Zn off line OK (on line run in 2 weeks from now) 2014 and beyond: suppression of surface ionized species using the LIST technique + development of requested beams: Cu, Sn (ISOLDE scheme) Ge, Se (difficult to very difficult) Laser beams are driven some 17 m away down to the TIS Page 19/

20 RIB developments and R&D in ISOL science Laser ionized RIBs at ALTO Page 20/

21 RIB developments and R&D in ISOL science Laser ionized RIBs at ALTO Validated with Ga beams: 287/297 nm nm Next run with Zn beams: 214 nm nm nm (f tripling) starting October 14th 2013 Laser schemes and optics settled with the support of ISOLDE-CERN EdgeWave pump laser (532 nm, 100 W, 10 KHz, 10 ns) 2 Radiant Dyes Narrowscan lasers ( nm) BBO doubling units ( nm) Page 21/

22 RIB developments and R&D in ISOL science Laser ionized RIBs at ALTO Design: engineering office of the Accelerators Division of IPN Tests: R&D group of ALTO Collaboration with Mainz University: T. Kron and K. Wendt Page 22/

23 Recent progress in the instrumentation of the secondary beam lines + short term perspectives

24 Progress in the instrumentation of the secondary beam lines beta-decay spectroscopy in the N=50 region experiments in the 78 Ni region at the PARRNe mass separator (Tandem/ALTO) Ga79 As82 Ge79 Ge80 Ge81 Ge85 Ge86 Ga80 Ga82 Zn81 Ga83 Zn82 Present limit of structure knowledge (at least few excited states are known) hot plasma ionization (1 µa deuteron primary beam) O. Perru PhD def. 10 th December 2004 Eur. Phys. J. A 28, 307 (2006) surface ionization (2-4 µa electron primary beam) M. Lebois PhD def. 23 th September 2008 PRC 80, (2009) B. Tastet PhD def. 13 th May 2011 Ga84 hot plasma ionization (1 µa deuteron primary beam) PRC 76 (2007) laser ionization To be done in October 2013 PhD A. Etile PRC 87, (2013) D. Testov PhD def. November 2013 laser ionization (10 µa electron primary beam) K. Kolos PhD def. September 2012 Accepted in PRC (2013) Page 24/

25 Progress in the instrumentation of the secondary beam lines beta-decay spectroscopy in the N=50 region new tape station : BEDO kicker-bender PARRNe mass separator focal plane PARRNe mass separator build up ion collection decay ion beam deviated time Mylar tape Large volume Ge detector (EUROGAM-1 French-UK loan pool) plastic scintilator Ge CLOVER (proto EXOGAM ) etotal (photo-peak 1.3MeV) ~2% T1/2 measurement: tape motion cycling Triggerless DAQ 400ps resolution time stamping Page 25/

26 Progress in the instrumentation of the secondary beam lines BEDO : BEta Decay studies at Orsay ancilary plastic BGO Compact geometry (max γ efficiency) γ background suppression BGO crystals 4π-β Ge 4p beta Ge β energy loss Compton Ge Ge plastic scintillator collection point Page 26/

27 Progress in the instrumentation of the secondary beam lines BEDO : BEta Decay studies at Orsay 4 EXOGAM small prototypes Source-cap distance = 5 cm measured e g (1 MeV) = 5-6 % (previous system 1-2%) beam entrance sensitivity 0.1 pps up to 5 Ge detectors 6 plastic detectors Anti-Compton belt Page 27/

28 Progress in the instrumentation of the secondary beam lines BEDO : BEta Decay studies at Orsay BEDO setup in gamma mode 4 small EXOGAM clovers gamma BEDO setup in neutron mode Dubna neutron detector TETRA (1 st physics exp. last year) neutron fast timing mode LaBr3 LaBr3 Ge BaF2 LaBr3 Distances / source : Ge detectors BGO shields Ge = 40 mm LaBr3 = 25 mm BaF2 et LaBr3 = 40 mm Plastique = 25 mm ~90 3 He tubes borated polyethylene shielding Page 28/

29 Direct b-delayed neutron emission measurement of 84 Ga with TETRA 83 As T 1/2 =13.4 s b 84 As T 1/2 =4.2 s b-n 83 Ge T 1/2 = 1.85 s b 84 Ge T 1/2 =0.954 s b-n b 84 Ga T 1/2 =0.085s Pn( 84 Ge)=10.2(9) B.Pfeiffer et al. Prog. Nucl. Energy 41, 39 (2002) others: 10.8(6), 9.5(20), 9(3) Pn D. Testov PhD work and Orsay- Dubna collaboration Yu Penionzhkevich, V. Smirnov and E. Sokol n g g g n Pn=70(15) K.-L.Kratz et al. Z.Phys. A340, 419 (1991) and B.Pfeiffer et al. Prog. Nucl. Energy 41, 39 (2002) Pn=80(15) C.J.Gross et al. Acta Phys.Pol. B40, 447 (2009) Pn=47(10) J.A.Winger et al Proc.4th. Intern. Conf. Fission and Properties of Neutron-Rich Nuclei, Sanibel Island, Florida (2007); Pn=74(14) J.A.Winger PRC 81, (2010) TETRA detector at BEDO setup: - 4Pi neutron detector 90 counters 3 He 7 atm [measured eff. 63±5% (on line)] - 4p beta detector - 1 Ge detector - movable tape

30 Progress in the instrumentation of the secondary beam lines TETRA and BEDO in sequential mode dipole ON -> towards BEDO TETRA dipole OFF -> towards TETRA BEDO BEDO TETRA RIB on tape decay tape motion RIB on tape decay Collaboration IPN-FLNR Orsay-Dubna Expected on line June 2014

31 experiments scheduled with TETRA and BEDO in the period > 2015 (PAC accepted proposals) 132 Sn region β-γ and β-n experiments Didierjean et al. Lozeva et al. mid-shell Ln s β-γ fast-timing Roussière et al. n-rich Se β-γ and β-n experiments Kurtukian Nieto et al. n-rich Ge β-γ and β-n experiments Duchêne et al. N=50 β-γ experiments Etile Verney et al. Astier et al Page 31/

32 Medium term projects

33 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO Physics at the right arm of the kicker-bender TETRA POLAREX TAS BEDO SPECOLOR (project) D. Yordanov et al Page 33/

34 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO Dilution Refrigerator Vertical beam line ALTO beam Page 34/

35 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO Low Temperature Nuclear Orientation AND Nuclear Magnetic Resonance Ge Detector The detail of the shape of the angular distribution depends on the particular transition: spins of the nuclear states involved, transition multipolarities, and also on the environment of the nuclei like the total magnetic field and the temperature. The good frequency -> the magnetic moment Provided the magnetic field and the temperature are known Hyperfine information Nuclear thermometer Page 35/

36 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO PolarEx Rejuvenation of the dilution cryostat Thermometry Electronics Acquisition control Preparation on the ALTO site Structure and platforms Faisceaulogie and beam line design letters of intent received OFF line measurements at CSNSM OFF line measurements at ALTO ON line measurements at ALTO Collaboration CSNSM Orsay: A. Astier, G. Audi, S. Cabaret, A. Etilé, C. Gaulard, G. Georgiev, S. Roccia LPSC Grenoble: G. Simpson IPN Orsay: F. Ibrahim, D. Verney INM : L. Risegari University of Tennessee, University of Oxford N.J. Stone University of Maryland,University of Oxford J.R. Stone University of Novi Sad : M. Veskovic J. Nikolov

37 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO Possible and/or interesting measurements at ALTO N=50 Z= Sn N=82 78 Ni Z=28 Page 37/

38 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO LoI for the OFF Line phase : example Measurement of the magnetic moment of 77Ge Properties of neutron-rich nuclei between N = 40 and N = 50 shell closures Ge 45 with J p =7/2 + This level could easily be reproduced by Coriolis-coupling model or 2d 5/2 contribution to the wave function measurement : < 1 Lost of collectivity, no permanent deformation? 1 Similarity with Se 45? n Coriolis mixing? This measurement will allow the first direct evidence of the stability of deformation enhanced by Z=32 effect Page 38/

39 Progress in the instrumentation of the secondary beam lines Nuclear orientation on line: the POLAREX project at ALTO LoI for the ON line study: example 134Sb*, 136I*, 137I* Measurement of magnetic moment of isomeric states 132 Magnetic properties of nuclei close to 50 Sn 82 to test neutron-proton interactions in shell-model calculations Shell-model calculations unable to reproduce this drop measurements of 134 Sb*, 136 I*, 137 I* Level systematics of the neutron-rich odd-mass Sb isotopes J. Shergur et al., Phys. Rev. C65, (2002) Energy of the pd 5/2 orbit drops unexpectedly for Sb (N=82) and I (N=82) Page 39/

40 Progress in the instrumentation of the secondary beam lines TAS: Total Absorption Spectroscopy program Physics at the right arm of the kicker-bender TETRA POLAREX TAS BEDO SPECOLOR (project) Page 40/

41 Progress in the instrumentation of the secondary beam lines TAS: Total Absorption Spectroscopy program Pandemonium effect**: TAS Technique Due to the use of Ge detectors to measure the decay schemes: lower efficiency at higher energy underestimate of β branches towards high energy excited states: overestimate of the high energy part of the FP β spectra Solution: Total Absorption Spectroscopy (TAS) Big cristal, 4π => A TAS is a calorimeter! Picture from A. Algora ** J.C.Hardy et al., Phys. Lett. B, 71, 307 (1977) 12 BaF 2 covering ~4π Detection efficiency of γ ray cascade ~ 100% Si detector for β 41 TAGS developed by the Valencia team (Spain, B. Rubio, J.L. Tain, A. Algora et al.) : Proceedings of the Int. Conf. For nuclear Data for Science and technology (ND2013)

42 Progress in the instrumentation of the secondary beam lines TAS: Total Absorption Spectroscopy program More on TAS: Z. Issoufou s talk, this session Page 42/

43 Progress in the instrumentation of the secondary beam lines TAS: Total Absorption Spectroscopy program Existing TAS measurements 146 Gd 2 nd FP 100 Sn Superallowed A~74 N~Z 1 st FP A. Algora, B. Rubio, J.-L. Taín IFIC-Valencia Page 43/

44 Progress in the instrumentation of the secondary beam lines TAS: Total Absorption Spectroscopy program Possible TAS measurements at ALTO 100 Sn 146 Gd 2 nd FP 1 st FP 132 Sn 78 Ni Proposed TAS measurements Nuclear magic nuclei Astrophysics: r-process Fundamental physics Reactor physics, Decay Heat Reactor antineutrino spectra Page 44/

45 Proposed ALTO The TAS Collaboration: J. Agramunt 1, A. Algora 1, J. Äystö 4, V.M. Bui 2, D. Cano-Ott 5, C. Domingo-Pardo 1, V. Eloma 4, E. Estévez 1, T. Eronen 4, M. Fallot 2, W. Gelletly 3, G. Giubrone 1, J. Hakala 4, A. Jokinen 4, M.D. Jordan 1, A. Kankainen 4, E. Mendoza 5, F. Molina 1,,I. Moore 4, S.E.A. Orrigo 1, A. Pérez 1, Zs. Podolyák 3, H. Penttilä 4, A. Porta 2, P. H. Regan 3, S. Rice 3, J. Rissanen 4, B. Rubio 1,J.L. Taín 1, E. Valencia 1, C. Weber 4, A. Zakari 2 + IGISOL people 1 IFIC, CSIC-Univ. Valencia, Valencia, Spain 2 Subatech, CNRS/IN2P3, Univ. Nantes, EMN, Nantes, France 3 Univ. Surrey, Guilford, UK 4 IGISOL, Univ. Jyväskylä, Finland 5 Ciemat- Madrid, Spain Experiment proposals for ALTO with different steps: Phase 1 ( ): Test experiment: install the Valencia-Surrey ALTO (12 BaF 2 ) & use the existing beam line, for nuclei of interest that could be easily selected Phase 2 ( ): more challenging cases that desserve to develop new selection patterns with the Laser ion source, in parallel development of a dedicated TAS beam line Phase 3 ( ): Synergy with the BEDO and TETRA devices, for beta-n emitters and going for more exotic isotopes => common measurement campaigns with complementary beam lines? In parallel, ideas for new detector developments combining higher resolution with efficiency: a set of LaBr 3 or CeBr 3, for ALTO then SPIRAL2. Page 45/

46 Rome was not built in a day R&D on RIB developments LE (no post acc.) physics program closely connected R&D and physics at ALTO paves the way towards SPIRAL2 phase 2 (initiate some parts of the physics program, train the next generation of nuclear physicists to the ISOL technique, prepare the instruments and methodologies etc)