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Experiments with rare isotopes The limits of experiments at the limits of stability Thomas Glasmacher Michigan State University.


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Experiments with rare isotopes The limits of experiments at the limits of stability Thomas Glasmacher Michigan State University The 2nd LACM-EFES-JUSTIPEN Workshop Joint Institute for Heavy Ion Research, Oak Ridge, Tennessee, USA Oak Ridge National Laboratory January 23-25, 2008
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Slide 1

Explores different avenues regarding uncommon isotopes The points of confinement of examinations at the cutoff points of solidness Thomas Glasmacher Michigan State University The second LACM-EFES-JUSTIPEN Workshop Joint Institute for Heavy Ion Research, Oak Ridge, Tennessee, USA Oak Ridge National Laboratory January 23-25, 2008

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Calculated noticeable Nature Insight Experiment Theory Measured discernible Progress Our common objective: To add to a prescient hypothesis of nuclear cores and their responses Optimize progress by contributing assets admirably: Measure observables that can (on a fundamental level) be figured Calculate observables that (on a fundamental level) can be checked in tests

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Rare isotopes are a shrewd venture and Tasks for experimenters Stable cores are very much depicted with shut shell cores as key benchmarks Rare isotopes show proof for vanishing of standard shell crevices, appearance of new shell holes, decrease of twist circle power, impact of continuum states Experimental errand: Quantify changes experienced in uncommon isotopes and measure with characterized assurance observables that are measurable and can be utilized to separate between speculations

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Facts of life for experimentalists responded shaft bar target N obs/e = N R = N T × N B × s N obs watched reactions e location effectiveness N R response rate N T nuclear thickness of target N B pillar rate s cross segment

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Facts of life for experimentalists responded bar target Build more proficient finders Make more bar Given by nature N obs/e = N R = N T × N B × s Use focuses with additionally scrambling focuses N obs watched reactions e identification productivity N R response rate N T nuclear thickness of target N B bar rate s cross area

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Stopped bar tests Possible trials and nature of observables rely on upon number of bar particles Discovery (couple of particles aggregate) Half live (couple of ten particles) Mass (couple of hundred particles) Fast bar tests Possible investigations and nature of observables rely on upon glow Interaction radii (couple of particles every hour) g-variables (several particles for each second) Fast bar tests (cont’d) Excited state energies, move lattice components Elastic and inelastic disseminating (ten particles for every second) Electromagnetic Hadronic Lifetimes from g - beam line shapes (many particles every second) Occupation numbers Nucleon evacuation Single nucleon (particles every second) Two-nucleon (many particles every second) Multi-nucleon (several particles for every second) Nucleon option (many particles every second) Experimental observables in examinations with in-flight delivered uncommon isotope bars

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S800 investigation line Stopped bar test: Discovery of new isotopes close to the n - dripline: 40 Mg, 42 Al, 43 Al, 44 Si 1990: GANIL Guillemaud-Mueller et al ., Z. Phys. A 332, 189 1997: GANIL Tarasov et al ., Phys. Lett. B 409, 64 1999: RIKEN Sakurai et al ., Phys. Lett. B 448, 180 2002: RIKEN Notani et al ., Phys. Lett. B 542, 49 GANIL Lukyanov et al ., J. Phys. G 28, L41 2007: NSCL Tarasov et al , Phys. Rev. C 75 (2007) 064613; Baumann et al , Nature 449 (2007) 1022 2007 4 x 10 17 48 Ca bar particles Two-stage separator (one-stage did not give adequate tidy up) First perception of 40 Mg (3 occasions), 42 Al, 43 Al

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Stopped pillar trial: Mass estimation Stop quick outlandish shafts in gas cell, concentrate, and utilization in investigations Penning trap mass estimations of uncommon isotopes delivered in-flight: Since Summer 2005: 33 Si, 29 P, 34 P 37 Ca, 38 Ca 40 S, 41 S, 42 S, 43 S, 44 S 63 Ga, 64 Ga 64 Ge, 65 Ge, 66 Ge 66 As, 67 As, 68 As, 80 As 68 Se, 69 Se, 70 Se, 81 Se, 81m Se 70m Br, 71 Br 66 As: T 1/2 = 96 ms LEBIT:  m  20 keV,  m/m  3x10 - 7 20-fold enhanced masses in district discriminating to rp process 38 Ca: T 1/2 = 440 ms, 0 +  0 +  + - emitter new contender for the test of the preserved vector current (CVC) theory ME LEBIT = - 22058.53(28) keV d m = 280 eV, d m/m=8 · 10 - 9 AME 03:  m = 5 keV G. Bollen et al . Phys. Rev. Lett. 96 (2006) 152501

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C. Thibault et al : PRC 12 (1975) 646 31,32 Na, nearby increment of S 2n  N=20 shell hole diminished X. Campi et al : NPA 251(1975) 193 clarified by misshapening through filling of n (f 7/2 ) C. Detraz et al : PRC19 (1979) 164 32 Na  32 Mg b-rot, low 2 + in 32 Mg E. Warburton et al : PRC 41 (1990) 1147 Z=10-12 and N=20-22 have ground state wavefunctions overwhelmed by n (sd) - 2 (fp) +2 setups T. Motobayashi et al : PLB 346 (1995) 9 vast B(E2;0 +  2 + ) in 32 Mg See likewise 29 Na V. Tripathi et al . Phys. Rev. Lett. 94 (2005) 162501 (2005) 31 Mg G. Neyens et al . Phys. Rev. Lett. 94 (2005) 022501 (2005) 27 Ne A. Obertelli et al ., Phys. Lett B 633 (2006) 33 28 Ne H. Iwasaki et al. , Phys.Lett. B 620 (2005) 118 34 Al P. Himpe, G. Neyens et al . Phys.Lett. B 658 (2008) 203 Exploring the limits of Island of Inversion Single-neutron evacuation to search for negative equality states, demonstrating the vicinity of f 7/2 interloper designs in the ground condition of the guardian: ( 30 Mg, 29 Mg+ g ) ( 26 Ne, 25 Ne+ g ) ( 28 Ne, 27 Ne+ g ) ( 38 Si, 36 Mg+ g ) two-proton evacuation

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25 Ne level structure known A.T. Reed et al ., PRC 60 (1999) 024311 S. Padgett et al., PRC 72 (2005) 064330 25 Ne is very much portrayed in sd shell with no confirmation for gatecrasher states underneath 3 MeV No proof for interloper setups in the ground state wave capacity of 26 Ne N=20 32 Mg 33 Mg 34 Mg - 1n 31 Na 32 Na 33 Na 25 Ne 26 Ne 27 Ne 28 Ne 29 Ne 30 Ne 31 Ne 32 Ne Single-neutron expulsion from 26,28 Ne and 30 Mg J.R. Terry et al. , Phys. Lett. B 640 (2006) 86

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32 Mg 33 Mg 34 Mg - 1n 31 Na 32 Na 33 Na 25 Ne 26 Ne 27 Ne 28 Ne 29 Ne 30 Ne 31 Ne 32 Ne sd shell takes into account interloper setups Single-neutron expulsion from 26,28 Ne and 30 Mg

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energized states  = 0,1 10.3 10.4 10.5 10.3 10.4 10.5 Single-neutron expulsion from 26,28 Ne and 30 Mg Ground states for 28 Ne, 30 Mg have critical 2 h w f 7/2 gatecrasher arrangements See additionally 31 Mg G. Neyens et al . Phys. Rev. Lett. 94 (2005) 022501 (2005) 27 Ne A. Obertelli et al ., Phys. Lett B 633 (2006) 33 J.R. Terry et al. , Phys. Lett. B 640 (2006) 86

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36 Mg g.s. overwhelmed by 2 h w setups Monte-Carlo Shell Model (MCSM) estimations: SDPF-M cooperation of Y. Utsuno, T. Otsuka et al . N=20 38 Si + Reaction hypothesis: J.A. Tostevin and B.A. Cocoa, PRC 74, 064604 (2006), p n p n p n 38 Si: no noteworthy interloper arrangements in g.s. 36 Mg: MCSM predicts solid gatecrasher admixtures for the low-lying states 2p knockout from 38 Si comes to just 0h w parts in 36 Mg Comparison of measured cross segments and those computed expecting the number of inhabitants in 0h w segments of the last states by the direct 2p knockout response: Only 32(8)% and 38(8)% of the w.f. of the g.s. also, 2 + state, separately, are 0h w segments, the rest is proposed to be of interloper character Intruder mastery places 36 Mg inside the “Island of Inversion” A Gade et al ., Phys. Rev. Lett. 99, 072502 (2007)

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Many examinations at GANIL (MUST identifier) Some trials at MSU Thin focus to dodge precise and vitality straggeling of low-vitality protons Proton dispersing in reverse kinematics Normal kinematics Inverse kinematics F. Deface é chal et al. , PRC 60 (1999) 034615 p( 56 Ni,p’) at GSI G. Kraus et al. , PRL 73 (1994) 1773

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Inelastic diffusing to gauge move rates: Thick-target g - labeled inelastic proton dispersing Pioneering trial at RIKEN p ( 30 Ne, 30 Ne g ) Y. Yanagisawa et al . PLB 566 (2003) 84 Hydrogen has the most dissipating focuses per vitality misfortune Inelastic p disseminating utilizing two mixed drink shaft settings to study chains of isotopes open in a reliable methodology Determine energized state energies and collectivity towards N =28 Univ. Tokyo, RIKEN, Rikkyo Univ., Michigan State Univ. joint effort Z Sulfur 40 Si Silicon RIKEN/Kyushu/Rikkyo LH 2 target: H. Ryuto et al ., NIM A 555 (2005) 1 30 mm width 9 mm thick, ostensible Negligible contaminant responses 36 Si N

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Evolution of 2 + energies towards N =28 40 Si Above Z =20 Ti, Cr and Fe 986(6) keV Below Z =20 Si, S and Ar 1.5 million 40 Si bar particles s p,p’ = 20(3) mb ~30 checks in the photopeak Low vitality characteristic of neutron collectivity in 42 Si Discovery of low-lying 2 + state in 42 Si at GANIL B. Bastin, S. Gr é vy et al. PRL 99 , 022503 (2007) C.M. Campbell et al. , PRL 97 (2006) 112501

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Two extra g - beams in discontinuity channel 42P-p-n States at 1.62(1) MeV and 1.82(1) MeV? Insufficient insights to test if the two moves are in occurrence Independent of the grouping, the second energized state is low in vitality In the shell model second energized state is ph-excitation crosswise over N =28 Low vitality backings narrowing of the N =28 hole in 40 Si Higher energized states in 40 Si C.M. Campbell et al. , PRL 97 (2006) 112501

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Evolution and character of collectivity Prior information from F. Marã©chal et al , PRC 60 , 034615 (1999) P.D. Cottle et al ., PRL 88 , 172502 (2002) N Enhanced collectivity towards N=28 in silicon Sulfur moves from vibrational mid-shell to rotational towards N=28 Silicon vibrational mid-shell Rotational point of confinement Sulfur Silicon Vibrational cutoff C.M. Campbell Ph.D. PLB 652 (2007) 169

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Traditionally performed in typical kinematics at lower bar energies, e.g. ( d , n ), ( 3 He, d ), ( a , t ), … At higher energies force less very much coordinated Trick: Pickup of an emphatically bound nucleon S