58 Ni(p, n) 58 Cu E p = 160 MeV 58 Ni( 3 He, t) 58 Cu E = 140 MeV/u Counts Excitation Energy (MeV) Comparison of (p, n) and ( 3 He,t) ０ o spectra Y. Fujita et al., EPJ A 13 (’02) 411. H. Fujita et al., PRC 75 (’07) J. Rapaport et al. NPA (‘83) GTGR

*GT (  ) : Important weak response, simple operator Yoshitaka FUJITA (Osaka Univ.) New Era of Nuclear Physics in the Cosmos RIKEN August 25-26, 2008 Nuclear Weak and EM Response Studied by Intermediate-energy Nuclear Reactions ( 中間エネルギー核反応による原子核弱電磁応答）   -decay : absolute B(GT), but only low-lying states ( -induced reactions: no chance !)  CE reaction : relative B(GT), but highly excited region

*GT (  ) : Important weak response, simple operator *E1 : Important electro-magnetic response  (  ’) [NRF] : up to particle threshold  (g, n) : above particle threshold  inelastic SC. at 0 o : Coulomb Ex. + Nucl. Ex. Yoshitaka FUJITA (Osaka Univ.) New Era of Nuclear Physics in the Cosmos RIKEN August 25-26, 2008 Nuclear Weak and EM Response Studied by Intermediate-energy Nuclear Reactions ( 中間エネルギー核反応による原子核弱電磁応答）   -decay : absolute B(GT), but only low-lying states ( -induced reactions: no chance !)  CE reaction : relative B(GT), but highly excited region

mainly by  &  Langanke & Martinez-Pinedo Rev.Mod.Phys.75(’04)819 (A,Z)=nuclei in the Fe, Ni region  -decay, e-capture, -induced reactions Balantekin & Fuller J.Phys.G 29(’03)2513 Crucial Weak Processes during the Core Collapse Gamow-Teller (GT) transitions

Simulation of  -decay spectrum

Direct Reactions with Light Projectiles Projectile 3 He Target Coulomb Excitation Elastic Scattering Inelastic Scattering Pick-up Stripping Charge-exchange Similarity with  decay! by Berta Rubio |i>  |f>  -int. Ejectile t

 -decay & Nuclear Reaction  GT  -decay tra. str. = B(GT) : reduced GT transition strength (matrix element) 2 *Nuclear (CE) Reaction Cross-section = reaction mechanism x operator x structure =(matrix element) 2 A simple reaction mechanism should be achieved ! we have to go to high incoming energy

 -decay & Nuclear Reaction  GT  -decay strength = B(GT) : reduced GT transition strength (matrix element) 2 *Nuclear (CE) Reaction cross-section = reaction mechanism x operator x structure =(matrix element) 2 A simple reaction mechanism should be achieved ! we have to go to high incoming energy Study of Weak Response of Nuclei by means of Strong Interaction ! using  -decay as a reference

***Derivation of B (GT) strength***

B (GT) derivation

Nucleon-Nucleon Int. : E in dependence at q =0 V  VV VV VV central-type interactions Simple one-step reaction mechanism at intermediate energies! Energy/nucleon Strength Love & Franey PRC 24 (’81) 1073

N.-N. Int. :  & Tensor-  q-dependence  TT largest at q=0 ! larger than others ! Love & Franey PRC 24 (’81) 1073

B (GT) derivation

58 Ni(p, n) 58 Cu E p = 160 MeV 58 Ni( 3 He, t) 58 Cu E = 140 MeV/u Counts Excitation Energy (MeV) Comparison of (p, n) and ( 3 He,t) ０ o spectra Y. Fujita et al., EPJ A 13 (’02) 411. H. Fujita et al., PRC 75 (’07) J. Rapaport et al. NPA (‘83) GTGR

**Connection between  -decay and ( 3 He,t) reaction** by means of Isospin

Nucleon & Coin = Coin back front = Nucleon isospin T=1/2, 3/2, … T z =1/2T z = -1/ Si Al 14 T z = (1/2)N + (-1/2)Z *z-component: conserved

Nuclei & Coin = Coin back front = Nuclei isospin T=1 triplet Mg 14 T z = +1T z = Si 12 T z = Al 13 Symmetry in 1)structure 2)transitions

Transitions in real & isospin space (T=1) Mg Si Al 13 T z =-1 T z = 0 T z =+1

26 Mg Z=12, N=14 26 Al Z=13, N=13 26 Si Z=14, N=12 T=1 symmetry : Structures & Transitions

26 Mg(p, n) 26 Al & 26 Mg( 3 He,t) 26 Al spectra R. Madey et al., PRC 35 (‘87) 2001 Y. Fujita et al., PRC 67 (‘03) Prominent states are GT states and the IAS ! IAS, 0 +

B(GT) values from Symmetry Transitions (A=26) Y. Fujita et al., PRC 67 (‘03)   -decay ( 3 He,t)

26 Mg( 3 He,t) spectra

Relationship: Decay and Width Heisenberg’s Uncertainty Priciple Width  E *if:Decay is Fast, then:Width of a State is Wider ! *if  t = sec   E ~100 keV (particle decay  t = sec   E ~ 1 eV (fast  decay)

Importance of Isospin : in p-decay of 26 Al

26 Mg( 3 He,t) spectra Information on: Excitation Energy Transition Strength Decay Width

B(GT) values from Symmetry Transitions (A=34) normalized Y. Fujita et al., PRC 75 (’07)

High-resolution Experiment -beam matching techniques- （ dispersion matching techniques)

RCNP Ring Cyclotron Good quality 3 He beam (140 MeV/nucleon)

Grand Raiden Spectrometer Large Angle Spectrometer 3 He beam ( 3 He, t) reaction

Beam line WS-course at RCNP T. Wakasa et al., NIM A482 (’02) 79. Dispersion Matching Techniques

Matching Techniques

RCNP, Osaka Univ. Dispersion Matching Techniques were applied!  E=150 keV  E=30 keV

Supernova Cycle

 important Langanke & Martinez-Pinedo Rev.Mod.Phys.75(’04)819 (A,Z)=nuclei in the Cr, Mn, Fe, Co, Ni region pf -shell Nuclei ! Crucial Weak Processes during the Core Collapse Balantekin & Fuller J.Phys.G 29(’03)2513

GT strengths in A=42-58 GT-GR

**Derivation of “absolute” B(GT) values  -decay: T 1/2 and absolute B(GT) values but only for the low-lying states *( 3 He,t) reaction: highly-excited states can be accessed but only the relative B(GT) values Let’s combine these data !

Mirror nuclei 46 Ti 50 Cr 54 Fe 50 Fe 54 Ni 46 Cr ß+ ( 3 He,t) N=Z T=1 Isospin Symmetry in pf-shell Nuclei Ni Fe 28 T z =0 T z =1 T z =-1 Leuven Valencia Surrey Osaka GSI by B. Rubio

Nuclei & Coin = Coin back front = Nuclei isospin T=1 triplet Cr 26 T z = +1T z = Fe 24 T z = Mn 25

Isospin Symmetry Transitions: 50 Cr( 3 He,t)  50 Mn   -decay 50 Fe Q EC =8.152(61) MeV T 1/2 =0.155(11) s (Z,N)=(24,26)(25,25)(26,24) B(GT)=0.60

**Reconstruction of  decay from ( 3 He,t) ---assuming isospin symmetry ---

Simulation of  -decay spectrum relative intensities of  -decay feeding are deduced ! Y. Fujita et al. PRL 95 (2005)

Absolute B(GT) values -via reconstruction of  -decay spectrum-  -decay experiment T 1/2 =0.155(11) s GT tra. to the 0.65 MeV state New value B(GT)=0.50(13) *20% smaller than deduced in the  -decay: 0.60(16) Absolute intensity: B(GT) Y. Fujita et al. PRL 95 (2005) B(F)=N-Z Relative feeding intensity from ( 3 He,t) t i =partial half-life

Mirror nuclei 46 Ti 50 Cr 54 Fe 50 Fe 54 Ni 46 Cr ß+ ( 3 He,t) N=Z T=1 Isospin Symmetry in pf-shell Nuclei Ni Fe 28 T z =0 T z =1 T z =-1 Leuven Valencia Surrey Osaka GSI CNS by B. Rubio

54 Ni  -decay measurement 54 Ni S p =4.35 Q =8.800  + decay g.s. IAS at Louvain la Neuve (ISOL facility) at GSI (FRS facility) T 1/2 =0.115(4) s

Absolute B(GT) values in 54 Ni  -decay -via reconstruction of  -decay spectrum-  -decay exp. at LLN (Belgium) T 1/2 =0.115(4) s New value B(GT)=0.46(8) Absolute intensity: B(GT) B(F)=N-Z Relative feeding intensity from ( 3 He,t) t i =partial half-life B(GT) : 1 st 1 + state at MeV *old  -decay value : 0.68(16) ( assuming no higher Ex states) * 54 Fe(p,n) 54 Co value : 0.74(5)

54 Ni  -decay measurement 54 Ni S p =4.35 Q =8.800  + decay g.s. IAS at Louvain la Neuve (ISOL facility) at GSI (FRS facility) Accurate ratio of  -ray intensity

GSI: RISING set up - active stopper campaign - 3-layors of DSSD active stopper FRS

GSI RISING set up Active Beam Stopper Campaign July-August, 2007

RCNP, Osaka (b) (a) RISING, GSI

RCNP, Osaka RISING, GSI B(GT) ( 3 He,t) B(GT)  -decay Comparison *B(GT) values using T 1/2 =115 ms （ Louvain)

Mirror nuclei 48V48V 52 Mn 56 Co 52 Co 56 Cu 48 Mn ++ ( 3 He,t) N=Z T = 2 Isospin Symmetry in pf-shell Nuclei Ni Cr 28 T z =0 T z =1 T z =-1 52 Ni T z =2 T z =-2 52 Cr 48 Cr 52 Fe 56 Ni 56 Fe 56 Zn 48 Ti 48 Fe by Y. Fujita, B. Rubio How is the T 1/2 value?

Comparison: (p, n) and ( 3 He,t) IAS g.s. 52 Cr(p, n) 52 Mn Ep =120 MeV D. Wang et al., NP A480 (’88) 285

 -decay simulation x R 2 / 2 for IAS (correction of coupling constant) f-factor

 -decay Half-life T 1/2 -via reconstruction of  -decay spectrum- abs. B(GT) distribution from ( 3 He,t) B(F)=N-Z

52 Ni  -decay Half-life T1/2  -decay exp. (C. Dossat et al., NPA 792, 18 ’07 ) T 1/2 = 40.8(2) ms GANIL abs. B(GT) distribution [ 52 Cr( 3 He,t)] Q EC =11.88 MeV [  -decay + IMME (‘06)] B(F)=N-Z Isospin symmetry estimation T 1/2 = 39 (3) ms SM cal. (PRC 57, 2316, ’98) T 1/2 = 50 ms Mass formula (T. Tachibana et al.) T 1/2 = 35 ms Uncertainty of the Q-value should still be considered !

The Layer Structure of Nature (Snake of Uroboros) What are other connections between the world of Nuclear Physics & Astrophysics?

E1 Coulomb Excitation dipole excitation

E1-distribution: Low-lying & GDR Low-lying region: studied by (  ’) [NRF] Higher-Ex region: studied by (  n) Gent data Livermore data 58 Ni( ,  ’) 58 Ni(  n) 68

Livermore data 58 Ni(p, p’), 160 MeV at 0 o Livermore data 58 Ni(  n) 8 (p, p’) & ( , n) IUCF data

26 Mg( ,  ’) FZR NRF data

26 Mg(p, p’) A. Tamii et al.. RCNP

26 Mg(p, p’) & E1 Good proportionality !

E-field: Time dependence E max = z 1 e  Intensity dI(  )/d  | max = (c/2  )(z 1 e  ) 2 (p, p’) 300 MeV  =1.3, z=1 Intensity=1.69(c/2p)e2 ( 3 He, 3 He’) 160 MeV/u g=1.17, z=2 Intensity=5.48(c/2  )e 2

Summary * Weak response of Nuclei was studied by using Strong Int. --Charge Exchange Reaction-- * Isospin Symmetry was introduced. * High resolution of the ( 3 He,t) reaction allowed the comparison of analogous transitions * Absolute B(GT) strengths were derived. * High resolution (p, p’) and/or ( 3 He, 3 He’) allows the study of B(E1) strengths. Collaboration of Experimentalists and Theorists is very important!

High-Resolution Collaborations Bordeaux (France) :  decay GANIL (France) :  decay Gent (Belgium) : ( 3 He, t), (d, 2 He), (  ’), theory GSI, Darmstadt (Germany) :  decay, theory ISOLDE, CERN (Switzerland) :  decay iThemba LABS. (South Africa) : (p, p’), ( 3 He, t) Jyvaskyla (Finland) :  decay Koeln (Germany) :  decay, ( 3 He, t), theory KVI, Groningen (The Netherlands) : (d, 2 He) Leuven (Belgium) :  decay LTH, Lund (Sweden) : theory Osaka University (Japan) : (p, p’), ( 3 He, t), theory Surrey (GB) :  decay TU Darmstadt (Germany) : (e, e’), ( 3 He, t) Valencia (Spain) :  decay Michigan State University (USA) : theory, (t, 3 He) Muenster (Germany) : (d, 2 He), ( 3 He,t) Univ. Tokyo and CNS (Japan) : theory,  decay