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Structure evolution towards 78 Ni : challenges in the interpretation of hard-won experimental data solved by simple means David Verney, IPN Orsay FUSTIPEN Topical Meeting -- « Recent Advances in the Nuclear Shell Model » -- June 19-20, 2014, GANIL, Caen An introduction to the N=50 shell effect/evolution towards 78 Ni How and why the subject was introduced in Orsay What we have learned ? Selection of results (from Orsay and elsewhere) : collectivity and evidence of intruder states in the 78 Ni region
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Page 2 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 An introduction to the N=50 shell effect/evolution towards 78 Ni
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Page 3 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 The 78 Ni region in 2014: the final cut (?) Age of the pionneers: mid 80’s TRISTAN(Brookhaven)/ OSIRIS(Studsvik) “Is the region above 78Ni doubly magic ?” r-process consequences Fogelberg, J.C. Hill, J.A. Winger and others The final cut ? : ca 2014 RIKEN direct study of 78 Ni By Kratz et al. PRC 38 (1988) Waiting point nucleus at N=50 80 Zn « » very busy decade dormance Second golden age : ca 2004 Yrast (LNL,Euroball) /Coulomb exc. (ISOLDE,ORNL) /Masses (JYFL,ISOLDE) /transfer (ORNL,ISOLDE) /Radioactivity(ORNL,Orsay) “Is N=50 a good magic number?” r-process + structure consequences
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Page 4 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 The persistence of N=50: the core-breaking states 32 p 1/2 g 9/2 d 5/2 neutrons 50 O. Sorlin, M.G. Porquet Prog. Part. Nucl. Phys. 61 (2008) 602 N=50 gap extrapolation → 78 Ni =3.0(5) MeV After a decade : no (serious) evidence was found for shell quenching down to Z=30 in the low energy data (radioactivity and coulomb excitations studies). But:
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Page 5 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 The question of the size of the gap at N=50: what masses say using data taken from AME2012 [including Hakala et al. PRL101 052502 (2008)] collective origin theoretically : Bender et al. Phys. Rev. C 78, 054312 (2008) maximum influence of beyond mean-field correlations = S 2n (52)-S 2n (50) extracted from Bender et al. Phys. Rev. C 78, 054312 (2008) d 5/2 – g 9/2 (MeV) Ni ZnGe SeKrSr Duflo Zuker gap PRC59 (1999) 90 Zr =4,7 MeV Duflo Zuker gap 78 Ni =5,7 MeV « standard » « graphical » local minimum at Z=32 Zr K. Heyde et al. Phys. Let. B176 (1986) NPA466 (1987) 189 « standard » « graphical »
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Page 6 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 K. Sieja and F. Nowacki, Phys. Rev. C 85, 051301R (2012) minimum in gap The question of the size of the gap at N=50: shell model
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Page 7 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 NPA466 (1987) 189 Z S n (Z,N)-S n (Z,N+1) S n (Z,N)-S n (Z,N extr ) N N+1 N+3 N+5 N+7 neutron number (Koopmans theorem) gap in the single particle levels 50 j’ j j’ = S n (Z,N) but S n (Z,N+1) is not a good prescription for for the evaluation of j one has to estimate j’ and j in the same nucleus j — j’ = S n (Z,N) —S n (Z,N extr ) then the good prescription becomes : The question of the size of the gap at N=50: back to core-breaking states p 1/2 g 9/2 d 5/2 neutrons 50 K. Heyde et al. graphical method NPA466 (1987) 189 There are more things than monopole effects in the red curve …
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Page 8 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 K. Sieja and F. Nowacki, Phys. Rev. C 85, 051301R (2012) The question of the size of the gap at N=50: back to core-breaking states Fusion-fission experiment accepted for AGATA@GANIL campaign (spokespersons G. Duchêne and G. De Angelis) search for core-breaking Yrast states in 80 Zn
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Page 9 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 figures taken from Bender et al. Phys. Rev. C 78, 054312 (2008) N=50 vs Z=50 situations
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Page 10 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 How and why the subject was introduced in Orsay (experimental context)
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Page 11 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Zn81 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) +PhD A. Etile CSNSM ongoing surface ionization (2-4 µA electron primary beam) M. Lebois PhD – def. 23 th September 2008 PRC 80, 044308 (2009) B. Tastet PhD – def. 13 th May 2011 PRC 87, 054307 (2013) D. Testov PhD – def. 17 th January 2014 laser ionization (10 µA electron primary beam) K. Kolos PhD – def. September 2012 PRC 88, 047301 (2013) Ga84 Ga83Ga82 Ga85 Ga80Ga79Ge80Ge79Ge81Ge85Ge86 As82 hot plasma ionization (1 µA deuteron primary beam) PRC 76 (2007) 054312 -decay spectroscopy at the PARRNe mass separator (Tandem/ALTO) Zn82 And “spin-off” elsewhere: -LNL :Plunger + AGATA + PRISMA -RIKEN: EURICA, MINOS campaigns accepted : GANIL Plunger + AGATA + VAMOS LoI: SPES, SPIRAL2 phase 2
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Page 12 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Tandem building Institut de Physique Nucléaire Campus of the Paris Sud University Orsay (France)
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Page 13 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 ALTO=ISOL installation based on photo-fission (the first of its kind in the world) PARRNe mass separator e-LINAC 10 µA 50MeV (former 1 st section of the CERN LEP injector) TIS vault >~1.10^11 fissions/s Target Ion-source ensemble kicker - bender secondary beam lines POLAREX nuclear orientation on line identification station BEDO beta decay spectroscopy and the only facility in France providing fission fragments as mass separated RIBs (prefiguring for a time SPIRAL2.2)
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Page 14 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 plastic scintilator Large volume Ge detector (EUROGAM-1 French-UK loan pool) Ge CLOVER (proto EXOGAM ) Mylar tape beam total photo-peak 1.3MeV) ~2% T1/2 measurement: tape motion cycling Triggerless DAQ 400ps resolution time stamping time decay ion beam deviated build up ion collection Detection setup and movable tape
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Page 15 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 β energy loss Compton collection point Ge plastic scintillator 4π-β4π-β Ge ancilary plastic BGO 4 beta BEDO : BEta Decay studies at Orsay Strategy for optimal detection Compact geometry (max γ efficiency) γ background suppression BGO crystals
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Page 16 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 BEDO : BEta Decay studies at Orsay construction completed – commissioning beam time in 2012 Anti-Compton belt 4 EXOGAM small prototypes Source-cap distance = 5 cm evaluated (1 MeV) = 3-4 % (previous system 1-2%) sensitivity 0.1 pps up to 5 Ge detectors 6 plastic detectors beam entrance
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Page 17 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 What we have learned ? Selection of results, collectivity and evidence of intruder states in the 78 Ni region
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Page 18 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Zn81 surface ionization B. Tastet PhD – def. 13 th May 2011 PRC 87, 054307 (2013) laser ionization (10 µA electron primary beam) K. Kolos PhD – def. September 2012 PRC 88, 047301 (2013) D. Testov PhD – def. 17 th January 2014 Ga84 Ga83Ga82 Ga85 Ga80Ga79Ge80Ge79Ge81Ge85Ge86 As82 Zn82 -decay spectroscopy around the Z=32 “curiosity”
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Page 19 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 isomerism in the N=49 line (3-5) Hoff & Fogelberg NPA368 (1981) 8+ 6+ 4+ 2+ 0+ ( g 9/2 -2 ) 8+ seniority isomer populated in DIC ●Makishima et al PRC 59 (1999) ●Podolyak et al Int. J. Mod phys E 13 (2004) ●H. Mach et al J. Phys. G 31 (2005) → T 1/2 =2.95(6) ns existence of second beta decaying state with I~7 suspected ISOLDE experiment, laser spectroscopy : two long lived states in 80 Ga I=3 and I=6 (negative parity from shell model) B. Cheal et al., PRC 82 (2010) 051302R
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Page 20 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Study of 80 Ga→ 80 Ge beta decay hits per 0.5 keV Energy (keV)
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Page 21 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 etc… Over the 75 γ-rays previously attributed to the 80 Ga decay, the decay time of 67 individual β-delayed γ- activities were measured the apparent half life of 30 levels could be determined Study of 80 Ga→ 80 Ge beta decay
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Page 22 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 measured half-life in seconds T1/2=1.687 0.011s Singh Nuclear Data sheets 105 (2005) 223 apparent half-life of the 80 Ge levels longer lived shorter lived Hoff & Fogelberg 235 U ALTO 238 U Study of 80 Ga→ 80 Ge beta decay
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Page 23 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 80 Ga longer shorter 80 Ge A (apparent half life) L longer lived state contribution shorter lived state contribution levels of 80 Ge S 10,80,60,40,20 F (indirect feeding apparent half life) Study of 80 Ga→ 80 Ge beta decay
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Page 24 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 80 Ga longer shorter T 1/2 = 1.9 0.1 s T 1/2 = 1.3 0.2 s 3―3― 6―6― Study of 80 Ga→ 80 Ge beta decay
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Page 25 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 M. Honma et al., Phys. Rev. C 80, 064323 (2009) B.A. Brown private communication, as first used in D. V. et al. Phys. Rev. C 76, 054312 (2007) JUN45 JJ4B multiplets close to the 0(6) limit of IBM
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Page 26 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Kumar model-independent n-body moments [Kumar PRL28, 249 (1972)] intrinsic shapes of SM eigenstates JUN45JJ4B shell model calculations and transcription into intrinsic shapes
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Page 27 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 microscopic origin of the collective features JUN45 JJ4B f 5/2 p 3/2 p 1/2 g 9/2 f 5/2 p 3/2 p 1/2 g 9/2 collective gamma-soft configurations f 5/2 p 3/2 p 1/2 g 9/2 non-collective quasi-particle like configurations ℓ=2 quadrupole components of the interaction pairing components of the interaction ► the energy proximity of f 5/2 and p orbits ( ℓ=2) seems to be the key ingredient energy separation between f 5/2 and p 3/2 in 79 Cu : ~1 MeV in JUN45 390 keV in JJ4B
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Page 28 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Triaxiality at Z=32
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Page 29 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 76 Ge 0 + 2 ? Triaxiality at Z=32 and possible intruder 2p-2h 0+ states at N=48 “triaxial features” evolution of the 0 + 2 state energy
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Page 30 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 80 Ge from M. Honma et al., Phys. Rev. C 80, 064323 (2009)
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Page 31 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Zn81 laser ionization (10 µA electron primary beam) K. Kolos PhD – def. September 2012 PRC 88, 047301 (2013) Ga84 Ga83Ga82 Ga85 Ga80Ga79Ge80Ge79Ge81Ge85Ge86 As82 Zn82 -decay spectroscopy around the Z=32 “curiosity”
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Page 32 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Lebois et al. Kolos et al. Study of 84 Ga 53 84 Ge 52 decay
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Page 33 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 (0 —,1 — ) Study of 84 Ga 53 84 Ge 52 decay
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Page 34 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 84 Ga 53 84 Ge 52 : addressing the collectivity development beyond N=50 0 0+ 2+ 710 1744 4+ 6+ 3095 1542 22+22+ 1934 02+02+ 2838 23+23+ HFB-5DCH Gogny D1S Delaroche et al. Bruyères-le-Châtel, available online, S. Hilaire M. Girod
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Page 35 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 84 Ga 53 84 Ge 52 : addressing the collectivity development beyond N=50 K. Kolos PRC 88, 047301 (2013) Shell model calculations
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Page 36 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 0 0+ 2+ 769 1584 4+ 6+ 2900 1530 22+22+ 42+42+ 2130 2002 31+31+ 2812 51+51+ 1768 02+02+ 2150 24+24+ 2603 43+43+ 1873 23+23+ 2360 32+32+ 346 370 405 269 166 229 231 599 77 137 145 0 0+ 2+ (1+,2+) (0+,1+,2+) 3502 (1+,2+) EXP 2228 1389 624 JJ4B(proton-proton)+Sieja et al PRC 79, 064310 (2009) (°) = 0 0+ 2+ 710 1744 4+ 6+ 3095 1542 22+22+ 1934 02+02+ 2838 23+23+ HFB-5DCH Gogny D1S
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Page 37 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 A bit deeper into the problem of intruder states: odd isotones N=49 What we have learned ? Selection of results collectivity and evidence of intruder states in the 78 Ni region
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Page 38 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Zn81Ga84 Ga83Ga82 Ga85 Ga80Ga79Ge80Ge79Ge81Ge85Ge86 As82 Zn82 PhD A. Etile (CSNSM Orsay) ongoing first data taken with the new -decay spectroscopy setup BEDO (BEDO commissioning) odd-odd nuclei: -detailed spectroscopy: stopped beam experiments - -decay very selective as allowed GT transitions e-e→o-o practically exclusively 0+→1+ A bit deeper into the problem of intruder states: the case of the odd-odd N=49 isotones
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Page 39 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 By Kratz et al. PRC 38 (1988) Waiting point nucleus at N=50 80 Zn By Winger et al. PRC 36 (1987) « » The anomalous occurrence of low lying 1+ states in the odd-odd N=49 isotone 80 Ga → historically launched the problematic of a possible vanishing of the N=50 shell effect
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Page 40 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Winger et al. PRC 36 (1987) Fig. taken from Kratz et al. PRC 38 (1988) RPA calculations, with significant quadrupole deformation (ε 2 =0.26) produce naturally an enormous amount of 1+ states (2QP states, Nilsson labeled), which was found satisfactory (!) in a similar study Winger et al removed the parenthesis only at much higher energy
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Page 41 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 In the observation of the beta decay of an even-even to an odd-odd nucleus : one cannot (in principle) “miss” the lowest 1+ states (only 0+→1+ beta transitions are allowed in n-rich nuclei) Q window Eidens et al (1970) Hoff & Fogelberg (1981) Winger et al (1987) note the huge increase in the number of states populated by beta decay between 82As and 80Ga -- is it real ? is there an important structure effect at play ?
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Page 42 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 H. Gausemel et al., Phys. Rev. C 70, 037301 (2004) 3.4(9) 80(20) 1.6(5) 0.35(9) B(%) log ft 5.7(2) 4.2(2) 5.3(2) 5.8(2) 3.5(5) 8.50(6) 1.45(2) <1 100(3) (0-,1-) (0,1) Study of 82 Ge→ 82 As beta decay (Still a bit preliminary)
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Page 43 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 what are the proton-neutron configurations one can expect at low energy ? → let’s start with the zero-order coupling O-ν even-even semi-magic core O-O O-π E-E proton open shell (proton quasi-particles) neutron closed shell (neutron holes and intruder states) odd-proton N=50 nucleus (taken from experimental level scheme) odd-neutron N=49 nucleus (taken from experimental level scheme) odd-odd N=49 nucleus (we hope to describe)
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Page 44 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Neutron states Omnipresence of positive parity (intruder) states First hinted at from transfer reaction data [e.g. Detorie et al PRC18 (1978)] First systematics proposed by Hoff & Fogelberg NPA 368 (1981) emphasized in Meyer et al. PRC 25 (1982) since then everybody has been quiet on the subject 1p-2h states 2 + p 1/2 -1 or f 5/2 -1,p 3/2 -1 ? 78 Zn(d,p) R. Orlandi et al. (REX-ISOLDE) 79-80 Cu -decay M. Niikura (EURICA RIKEN)
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Page 45 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 A. Pfeiffer et al. NPA 455 (1986) 381 Proton states
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Page 46 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 from beta-decay D.V. et al. PRC 76, 054312 (2007) Proton states 5/2 assignment to ground state unambiguously confirmed from laser spectroscopy measurements Cheal et al PRL 104, 252502 (2010) N.B. We will know more soon: 79 Cu has been populated in 80 Zn(p,2p) reaction at RIKEN recently (PhD work in Orsay under the supervision of S. Franchoo)
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Page 47 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 82As is the first N=49 isotone for which low-spin negative parity (0- and 1-) states appear below the first 1+ state Unperturbed positions of the proton-neutron configurations in the odd-odd N=49 isotones normal positive parity intruder negative parity
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Page 48 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Include 2d 5/2, 3s 1/2, 2d 3/2 on top of the fp-g valence space → very challenging for shell model, not yet available → what can be done ? → in a first approach, one can use a much less computationally demanding solution: core-particle coupling model → our job was facilitated and encouraged by : (1)The description of odd N=49 nuclei down to 85 Kr, including 2d 5/2, 3s 1/2, 2d 3/2 has already been done: Kitching Z. Phys. 258 (1973) ; Bhattacharya & Basu J. Phys. G 5 (1979) (2)Hoffmann-Pinther & Adams [NPA229 (1974)] have already treated the odd-odd case within the Thankappan-True [Phys. Rev. 137 (1965)] schematic approach Core QP π QP ν C - π C - ν π-ν interaction experimental values fit to the odd nuclei strength adjusted on 86Rb
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Page 49 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 experimental coupled to 0 + coupled to 2 + in agreement with identifications made by Dawson et al. Phys. Rev. 181 (1969)
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Page 50 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 experimental coupled to 0 + coupled to 2 + 3.4(9) 80(20) 1.6(5) 0.35(9) B(%) log ft 5.7(2) 4.2(2) 5.3(2) 5.8(2) 3.5(5) 8.50(6) 1.45(2) <1 100(3) (0-,1-) (0,1) only states coupled to 2 + 2 + core coupled states ? (clearly) π p 3/2 ν p 1/2 -1 intruder π f 5/2 ν d 5/2
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Page 51 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 Winger et al. PRC 36 (1987) Fig. taken from Kratz et al. PRC 38 (1988) RPA calculations, with significant quadrupole deformation (ε 2 =0.26) produce naturally an enormous amount of 1+ states (2QP states, Nilsson labeled), which was found satisfactory (!) in a similar study Winger et al removed the parenthesis only at much higher energy
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Page 52 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
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Page 53 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 The 78 Ni region in 2014: the final cut (?) Age of the pionneers: mid 80’s TRISTAN(Brookhaven)/ OSIRIS(Studsvik) “Is the region above 78Ni doubly magic ?” r-process consequences Fogelberg, J.C. Hill, J.A. Winger and others Second golden age : ca 2004 Yrast (LNL+Euroball) /Coulomb exc. (ISOLDE,ORNL) /Masses (JYFL+ISOLDE) /transfer (ORNL,ISOLDE) /Radioactivity(ORNL+Orsay) “Is N=50 a good magic number?” r-process + structure consequences Third golden age : ca 2014 RIKEN + elsewhere direct study of 78 Ni + around very busy decade dormance towards an even busier decade Conclusions the question of the gap minimum Z=32, its microscopic origin and general consequences : we have just scratched the subject rapid energy increase of the p1/2 hole states below Z=32 (N=40 gap) Below Z=32, even at low energy, there is no hope shell model calculations can do a good job without including some external orbits (obvious statement but cruel necessity for experimentalists’ interpretations) importance of the triaxial degree of freedom AND the intruder states
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Page 54 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 backup slides
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Page 55 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 90’s ending, beginning 2000’s, ISOL activity back at IPN: PARRNe converter (C) deuteron beam (1µA 26 MeV) fast neutrons 1+ ion source Fission Fragments target (10^9 fissions/s) 238 U fission mass separator detection from P.W.Lisowski et al, OECD/NEA Report NEANDC-305 'U' 1991 p.177 Thesis Nicolas Pauwels IPN Orsay initially a R&D test bench for the SPIRAL2 project « Production d’Atomes Radioactifs Riches en Neutrons » it all began with…
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Page 56 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 exploratory photofission experiment at CERN arrival of the LINAC cavity from decommissioned LEP injector construction of the LINAC bunker RF system First e-beam extracted UCx target on line with e-beam – production yields measurements Commissioning : tests and radiation safety measurements TIS vault 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 1999 1998 building of the low energy beam lines + laser ion source 2011 2012 2013 green light from French nuclear safety authorities BEDO commissioning first laser ionized RIB 83Ga -> 83Ge -decay 81Zn -> 81Ga -decay 84Ga -> 84Ge -decay initial idea of a R&D test bench for the SPIRAL2 project at the Orsay Tandem INAUGURATION ISOL available at TANDEM PARRNe mass-separator on line
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Page 57 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 BEDO LINO laser spectroscopy POLAREX TAS TETRA nuclear orientation on line (CSNSM) Total Absorption Spectroscopy (Subatech Nantes, IFIC Valencia) Pn measurements (IPN/FLNR) The ISOL installation at ALTO short and medium term projects
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Page 58 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 first experimental hint of proton evolution towards 78 Ni along the N=50 line very temptative, preliminary etc p3/2 f5/2 exactly consistent with Pfeiffer et al. NPA 455 (1986) 381 who provided sp energies, QP energies and v 2. proton ESPS (MeV) Z (N=50) g9/2 p1/2 Fermi level f7/2 allows to explain the J of 80 Ga and 80m Ga ISOLDE experiment, laser spectroscopy : two long lived states in 80 Ga J=3 and J=6 B. Cheal et al., PRC 82 (2010) 051302 extrapolation GaAsBrCuRb Page 58/ Verney – IPN Orsay Shell Model as Unified View of Nuclear Structure – 8-10 Oct. 2012
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Page 59 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 p3/2 f5/2 g9/2 p1/2 JW Lis JUN45 JJ4B Ji et Wildenthal Phys. Rev. C 38, 2849 (1988) A.F. Lisetskiy et al Phys. Rev. C 70, 044314 (2004) M. Honma et al Phys. Rev. C 80, 064323 (2009) A. Brown priv. com. used in Verney et al Phys. Rev. C 76, 054312 (2007) may be useful for shell model calculations in the 78 Ni region fitted SPE result from monopole migration (realistic N-N interactions) Sieja & Nowacki Phys. Rev. C 81, 061303(R) (2010) SN this work Page 59/ Verney – IPN Orsay Shell Model as Unified View of Nuclear Structure – 8-10 Oct. 2012
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Page 60 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
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Page 61 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 g 9/2 p 1/2 Z=37 Z=35 Z=33 Z=31 Z=29 N=49 78Ni 78Cu 80Ga 82As 84Br 86Rb N=50 p3 f5 ●●●●●● ●●●○ p3 f5 ●●●●●● ● p3 f5 ●●●●●○ p3 f5 ● ○○○ p3 f5 ●●●○○○ Z=38 88Sr p 3/2 f 5/2 90Zr p 1/2 g 9/2 d 5/2 s 1/2 d 3/2 p 3/2 f 5/2 86 Rb Dawson et al. Phys. Rev. 181 (1969) 2,3,4,5,6,7 3,4,5,6
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Page 62 Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014 g 9/2 p 1/2 Z=37 Z=35 Z=33 Z=31 Z=29 N=49 78Ni 78Cu 80Ga 82As 84Br 86Rb N=50 f 5/2 -1 g 9/2 -1 p 3/2 -1 g 9/2 -1 f 5/2 -1 g 9/2 -1 p 3/2 +1 g 9/2 -1 f 5/2 -1 g 9/2 -1 p 3/2 +1 g 9/2 -1 f 5/2 +1 g 9/2 -1 p 3/2 +1 g 9/2 -1 f 5/2 +1 g 9/2 -1 p 3/2 +1 g 9/2 -1 p3 f5 ●●●●●● ●●●○ p3 f5 ●●●●●● ● p3 f5 ●●●●●○ p3 f5 ● ○○○ p3 f5 ●●●○○○ p3/2 turns into particle character f5/2 turns into particle character Z=38 88Sr p 3/2 f 5/2 90Zr p 1/2 g 9/2 N=49 d 5/2 s 1/2 d 3/2 p 3/2 f 5/2
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