Breakup effects of weakly bound nuclei on the fusion reactions
Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy...
Transcript of Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy...
![Page 1: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/1.jpg)
![Page 2: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/2.jpg)
Heavy-ion fusion reactionsfor superheavy elements
1. H.I. sub-barrier fusion reactions2. Coupled-channels approach and barrier distributions3. Application to superheavy elements4. Hot fusion reactions of a deformed target5. Summary and discussions
Recent review article: K. Hagino and N. Takigawa, Prog. Theo. Phys.128 (‘12)1061.
Kouichi HaginoTohoku University, Sendai, Japan
New Frontiers in Nuclear Physics and Astrophysics-1, Akdeniz Univ., Antalya, Turkey, May 28 – June 1, 2018
![Page 3: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/3.jpg)
cf. Bohr ‘36
PT P+T
Fusion reactions: compound nucleus formation
compound nucleus
energy production in stars
nucleosynthesis superheavy elements
Fusion and fission: large amplitude motions of quantum many-body systems with strong interaction
microscopic understanding: an ultimate goal of nuclear physics
![Page 4: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/4.jpg)
fusion reactions in the sub-barrier energy region
1. Coulomb force : long range, repulsive2. Nuclear force : short range, attractive Coulomb barrier
Fusion reactions: compound nucleus formation
![Page 5: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/5.jpg)
Why sub-barrier fusion?
two obvious reasons:
superheavy elements
cf. 209Bi (70Zn,n) 278NhVB ~ 260 MeVEcm
(exp) ~ 262 MeV
83Bi
30Zn
113Nh 111Rg
fusion α decay
November, 2016
![Page 6: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/6.jpg)
Why sub-barrier fusion?
two obvious reasons:
nuclear astrophysics(nuclear fusion in stars)
cf. extrapolation of data
LOGARITMICSCALE
⇓
direct measurements
E0 Ecoul
Coulomb barrier
σ(E)
non-resonant
resonance
extrapolation needed !
figure: M. Aliotta
![Page 7: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/7.jpg)
Why sub-barrier fusion?
Two obvious reasons:discovering new elements (SHE)nuclear astrophysics (fusion in stars)
Other reasons: reaction mechamism
strong interplay between reaction and nuclear structure cf. high E reactions: much simpler reaction mechanism
many types of intrinsic degrees of freedom
energy dependence of tunneling probabilitycf. alpha decay: fixed energy
H.I. fusion reaction = an ideal playground to study quantum tunneling with many degrees of freedom
many-particle tunneling
![Page 8: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/8.jpg)
potential model: V(r) + absorption
cf. seminal work:R.G. Stokstad et al., PRL41(‘78) 465
Discovery of large sub-barrier enhancement of σfus
![Page 9: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/9.jpg)
154Sm 16O
θ
154SmEffects of nuclear deformation
154Sm : a typical deformed nucleus
![Page 10: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/10.jpg)
154SmEffects of nuclear deformation
154Sm : a typical deformed nucleus
154Sm 16O
θ
Fusion: strong interplay betweennuclear structure and reaction
deformation
![Page 11: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/11.jpg)
enhancement of fusion cross sections: a general phenomenon
strong correlation with nuclear spectrum→ coupling assisted
tunneling
potential model
![Page 12: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/12.jpg)
Coupled-channels method: a quantal scattering theory with excitations
many-body problem
still very challenging
![Page 13: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/13.jpg)
TDHF simulation
“ab-initio”, but no tunneling
TDHF = Time Dependent Hartree-Fock
S. Ebata, T. Nakatsukasa, JPC Conf. Proc. 6 (‘15) 020056
C. Simenel, EPJA48 (’12) 152
16O + 208Pb
![Page 14: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/14.jpg)
coupling
0+ 0+
0+ 0+
2+ 0+
Coupled-channels method: a quantal scattering theory with excitations
many-body problem
still very challenging
two-body problem, but with excitations(coupled-channels approach)
scattering theory with excitations
![Page 15: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/15.jpg)
Fusion barrier distribution [Rowley, Satchler, Stelson, PLB254(‘91)]
c.c. calculations
K.H., N. Takigawa, PTP128 (‘12) 1061
C.C. approach: a standard tool for sub-barrier fusion reactionscf. CCFULL (K.H., N. Rowley, A.T. Kruppa, CPC123 (‘99) 143)
singlechannel
![Page 16: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/16.jpg)
Fusion barrier distribution (Rowley, Satchler, Stelson, PLB254(‘91))
K.H., N. Takigawa, PTP128 (‘12) 1061a nice tool to understand the reaction dynamics
Data: J.R. Leigh et al., PRC52 (‘95) 3151
Vb
![Page 17: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/17.jpg)
Recent application to SHE : Quasi-elastic B.D.
48Ca + actinide target → SHE hot fusion reactions
= deformation reaction dynamics with barrier distributions?
fusion
quasi-elastic
Quasi-elastic scattering: reflected flux at the barrier a sum of elastic, inelastic,
and transfer easier to measure than
captureQuasi-elastic barrier distribution
H. Timmers et al., NPA584(’95)190K.H. and N. Rowley, PRC69(’04)054610
![Page 18: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/18.jpg)
T. Tanaka et al.,JPSJ 87 (‘18) 014201
S. Mitsuoka et al.,PRL99 (‘07) 182701
86Kr+208Pb
S.S. Ntshangase et al., PLB651 (‘07) 27
previous attempts
GARIS
![Page 19: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/19.jpg)
Analysis for a hot fusion reaction 48Ca + 248Cm
48Ca + 248Cm → 296116Lv*
K.H. and T. Tanaka (2017)(T. Tanaka et al., JPSJ 87 (‘18) 014201)
single-channel calculation (spherical 248Cm)
![Page 20: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/20.jpg)
Analysis for a hot fusion reaction 48Ca + 248Cm
48Ca + 248Cm (β2 = 0.297, β4 = 0.04) → 296116Lv*
K.H. and T. Tanaka (2017)
248Cm 48Ca
θ
[β2 and β4 from P. Moller]
![Page 21: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/21.jpg)
Analysis for a hot fusion reaction 48Ca + 248Cm
48Ca + 248Cm (β2 = 0.297, β4 = 0.04) → 296116Lv*
K.H. and T. Tanaka (2017)
1n transfer48Ca + 248Cm → 49Ca + 247Cm (Qgg = -1.06 MeV)
0+
3-
48Ca
4.5 MeV
![Page 22: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/22.jpg)
compound nucleus
re-separation(quasi-fission)
Connection to the ER cross sections
barrierdistribution
![Page 23: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/23.jpg)
Connection to the ER cross sections48Ca + 248Cm → 296
116Lv*
notion of compactness:D.J. Hinde et al., PRL74 (‘95) 1295
= more compact at the touching
→ favorable for CN
![Page 24: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/24.jpg)
CN
ER
Quasi-fission
fusion-fission
n
Tl
PCN
Wsuv
Extension of the fusion-by-diffusion modelK.H., arXiv: 1803.02036
Fusion-by-diffusion modelW.J. Swiatecki et al., Acta Phys. Pol. B34 (‘03) 2049
PRC71 (‘05) 014602
simplified C.C.
statistical model
diffusion of a 1D parabolic barrier (inner barrier)
![Page 25: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/25.jpg)
E
Pcap: quantummechanics
thermal fluctuation
2-body potential1-body potential
compoundnucleus heat up
re-separation
![Page 26: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/26.jpg)
CN
ER
Quasi-fission
fusion-fission
n
Tl
PCN
Wsuv
diffusion of a 1D parabolic barrier
sinj
sssd sinj
∆VVfiss(s)
Langevin in the overdamped limit:
![Page 27: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/27.jpg)
θ = π/2 (side collision)s(0)
inj
sinj sssd s(0)injsinj
∆VVfiss(s)
Extension of the fusion-by-diffusion modelK.H., arXiv: 1803.02036
![Page 28: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/28.jpg)
Extension of the fusion-by-diffusion modelK.H., arXiv: 1803.02036
![Page 29: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/29.jpg)
![Page 30: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/30.jpg)
![Page 31: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/31.jpg)
Summary and discussionsReaction dynamics for SHE formation reactions Recent measurement of barrier distributions with GARIS 48Ca + 248Cm coupled-channels analysis notion of compactness: ER formation
with side collisions
Open problems reaction dynamics?
quantum theory for friction
more data coming soon
cf. M. Tokieda and K.H., PRC95 (‘17) 054604
![Page 32: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/32.jpg)
Quantum friction
a quantization: Kanai model E. Kanai, PTP 3 (1948) 440)
time-dep. wave packet approach
∆E=5 MeV
M. Tokieda and K.H., PRC95 (‘17) 054604
classical eq. of motion
![Page 33: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/33.jpg)
Summary and discussionsReaction dynamics for SHE formation reactions Recent measurement of barrier distributions with GARIS 48Ca + 248Cm coupled-channels analysis notion of compactness: ER formation
with side collisions
Open problems reaction dynamics?
quantum theory for friction shape evolution with a deformed target?
how does the deformation disappear during heat-up? towards island of stability
more data coming soon
reaction dynamics with neutron-rich beams?
cf. M. Tokieda and K.H., PRC95 (‘17) 054604
![Page 34: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/34.jpg)
112113114115
165 170 175 180 185
neutron-rich beams: indispensable
how to deal with low beam intensity?
reaction dynamics of neutron-rich beams? capture: role of breakup and (multi-neutron) transfer? diffusion: neutron emission during a shape evolution? survival: validity of the statistical model?
structure of exotic nucleimore studies are required
Towards the island of stability
![Page 35: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/35.jpg)
formation of SHE
reaction dynamics
chemistry of SHE the origin of (S)HE
interdisciplinary SHE science with physics, chemistry, and astronomy
Nuclear Physics (RIBF/FRIB)
Astrophysics
structure of SHE
![Page 36: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/36.jpg)
FUSION20
Kouichi Hagino (co-chair) Tohoku UniversityKatsuhisa Nishio (co-chair) JAEA
November 16-20, 2020Shizuoka, Japan
![Page 37: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/37.jpg)
![Page 38: Heavy-ion fusion reactionshagino/talks/NNPA2018.pdf · Heavy-ion fusion reactions. for superheavy elements. 1. H.I. sub-barrier fusion reactions 2. Coupled-channels approach and barrier](https://reader033.fdocuments.net/reader033/viewer/2022053106/6070434883804b74df57600e/html5/thumbnails/38.jpg)