Heavy-ion Fusion and Fission Study at JAEA

Katsuhisa Nishio

Advanced Science Research Center

Japan Atomic Energy Agency

Tokai, JAPAN

IWM-EC, 2014, Catania, Italy

K. Nishio, H. Ikezoe, S. Mitsuoka, I. Nishinaka, H. Makii, Y. Wakabayashi, K. Hirose, K. Tsukada, M. Asai, Y. Nagame, A. Kimura, H. Harada

S. Hofmann, D. Ackermann, F.P. Heßberger, S. Heinz, J. Khuyagbaatar, B. Kindler, V.F.Comas J.A. Heredia, I. Kojouharov, B. Lommel, R. Mann, B. Sulignano, Ch.E. Düllmann, M.Schädel

S. Antalic, S. Saro

T. Ohtsuki, K. Hagino

A.G. Popeko, A.V. Yeremin, A. Svirikhin

Y. Watanabe

A. Yakushev, A. Gorshkov, R. Graeger, A. Türler

Y. Aritomo

A. Andreyev, D. Jenkins

S. Chiba

S. Yan N. Tamura, S. Goto

Tokai Campus, JAEA Tokyo

Tandem facility

J-PARC

Experimental Nuclear Physics Program at JAEA

◆ Fusion-Fission Study for Heavy-element Synthesis

◆ Multi-nucleon transfer-induced Fission and Surrogate Reaction

◆ Structure study for nuclei around 100Sn using JAEA Recoil Mass

Separator

◆ Neutron TOF measurement for fission and neutron-capture study

Tandem Facility

J-PARC

Contribution to Fukushima Issues

◆ New surveillance detector for criticality of melted fuel at

Fukushima power plant.

JAEA Tandem facility

20 MV Tandem accelerator (20UR) Super-conducting Booster Liniac ECR Ion Source on the terminal

Magnetic Spectrometer

Booster Liniac Recoil Mass Separator

Ge-detector array

ISOL ( p + 238U)

Radioactive target materials can be used Th, U, Np, Pu, Np, Am, Cm, Cf

Scattering Chamber

Fusion-Fission Study for Heavy Element

Synthesis

Super-heavy Nuclei

中性子数 　N

DbSg

BhHs

Mt

Rg

118

陽子数　Ｚ

Ds

Cn113

150 155 160 165 170 175 180 185

100

105

110

115

120

184

162

108

114

Cold Fusion (GSI,RIKEN)

Pb, Bi Targets

α

sf

EC

β-

Deformed Shell

120 48Ca + Actinide Target Nuclei

(FLNR)

Spherical Shell

Understanding for fusion using actinide target nuclei are

important to explore SHN

Neutron Number

Pro

ton

Nu

mb

er

Heavier Element

Using Radioactive Nuclei

Missing Region

14 92 108 108 0 34S + 238U 272Hs* 268Hs + 4 1n

Quasifission Fusion- Fission

1 atom

~ 3×1011

3.0×1011 6.6×1012

6.3×1012

(3) Evaporation (2) Fusion CN (1) Contact

Three steps for hｅａｖｙ-element synthesis

Fusion probability

Actinide Pb,Bi

z

A. Iwamoto, Nucl.Phys.A, 596 (1996) 329.

Orientation effects of target nucleus

Equatorial

High energy (above barrier)

Polar

Low energy (sub-barrier)

Effects of Nuclear Deformation on Fusion

Neutron

132Sn

238U

Pro

ton

Fusion-fission and Quasi-fission

78Ni

208Pb

274Hs (Z=108)

0

1

2

3

-150

-100

-50

0

50

-0.5

0.0

0.5

Pote

ntial E

ne

rgy 238U

Quasi-fission

36S

0

+

-

Fusion

Compund

Nucleus

Potential by Y. Aritomo

In-Beam Fission Measurement

Multi-Wire Proportional Counter

MWPC2 MWPC1

238U

Fission Fragment 1

Fission Fragment 2

238U target

200 mm

120 mm

5 mm

30Si, 31P, 36,34S, 40Ar, 40,48Ca Beams

Elab=179.0 MeV

100

101

102

103

Elab=173.4 MeV

100

101

102

103

Elab=167.8 MeV

100

101

102

103

Elab=162.2 MeV

100

101

102

103

Elab=156.5 MeV

100

101

102

103

Elab=150.9 MeV

100

101

102

103

Elab=145.3 MeV

100

101

102

103

Elab=140.8 MeV

fold (deg)

Eve

nts

100 110 120 130 140 150 160 170 180 190 20010

010

110

210

3

30Si + 238U

Folding Angle Distribution

Folding angle, θfold

Events

Nucleon-transfer Induced Fission Beam

FF 1 FF 2

Beam-like

θfold 238U-like

Full Momentum Transfer Fission Beam

FF 1 FF 2

θfold 268Sg

Orientation effects on fragment mass distributions in 36S + 238U

K. Nishio et al., Phys. Rev. C, 77 (2008) 064607.

Quasifission One-dimensional

Model

Deformation of 238U

Fission Fragment Mass Distributions

Low Incident Energy

High Incident Energy

238U

Fragment Mass Excitation Energy of CN

Cro

ss s

ection t

o p

roduce f

ragm

ents

(m

b)

Quasifission K. Nishio et al., Phys. Rev. C, 77, 064607 (2008).

K. Nishio et al., Phys. Rev. C, 82, 044604 (2010).

78 200 90 178

0

1

2

3

-150

-100

-50

0

50

-0.5

0.0

0.5

Dynamical calculation of nuclear shape – Fluctuation dissipation model －

Pote

ntia

l Energ

y (M

eV

)

272Hs

Quasifission

Fusion 238U

34S

CN

Fission Two center shell model

( 3 dimension )

V. Zagreabev, J. Phys. G, 31, 825 (2005).

Y. Aritomo et al., Nucl.Phys. A753, 152 (2005).

Y. Aritomo, Phys.Rev.C, 80, 064604 (2009).

Langevin Equation

Quasifission and Deep-quasifission

36S + 238U → 274Hs ( E*=35.5 MeV)

Charge Center Distance; Z

Mass

Asy

mm

etry

; α

Entrance Entrance

Fusion-fission Fusion-fission

Qiasifission Qiasifission

Deep quasifission Deep quasifission

Shape evolution (polar collision)

0 – 5 5 –10 10 –30 30 –50 > 50 Time (×10-21 s )

30Si + 238U

36S + 238U

CN

CN

Y. Aritomo et al., Phys. Rev. C 85, 044614 (2012).

Fusion probability

30Si + 238U 34S + 238U

Mass Mass

Cro

ss s

ectio

n (

mb

/2u

)

c.m. Energy (MeV)

29 %

33 %

37 %

41 %

46 % 15 %

11 %

7.5 %

4.9 %

3.6 %

Fusion Probability

All Fission Fragments

Fusion-Fission

Experimental Data

Histogram

Filled Area 264Sg

263Sg

268Hs

267Hs

Timing detector

Silicon strip detector

238U Targets

34S beams (2.0 – 2.5 pμA) in 2009

SHIP S. Hofmann and G.Münzenberg,

Rev. Mod. Phys. 72, 733 (2000).

Measurement of evaporation residue (ER)

cross sections at GSI

30Si + 238U = 268Sg*

30Si beams (1.0 pμA) in 2006

34S + 238U = 272Hs*

Hs isotopes produced in 34S + 238U

Ec.m.= 152 MeV

E* = 40 MeV

0.54 pb +1.3 - 0.45

1.8 pb +4.2 - 1.5

Ec.m. = 163 MeV

E* = 51 MeV

Yu.A Lazarev et al., 267Hs ( 2.5 pb ),

PRL75(1995) 1903.

New Isotope

Fusion and ER cross sections

34S + 238U 30Si + 238U

Fusion Cross

Section

×Fusion

Probability

×Survival

Probability

Cross sections for

SHN

(Statistical Model )

Qasifission Quasifission

Capture Cross

Section E Excitation energy Excitation energy

F

issio

n

Cro

ss s

ectio

n (

mb)

Fis

sio

n

cro

ss s

ection (

mb)

Eva

po

ratio

n R

esid

ue

C

ross s

ection (

mb)

Eva

po

ratio

n R

esid

ue

C

ross s

ectio

n (

mb

)

Energy in c.m. (MeV) Energy in c.m. (MeV)

K. Nishio et al., PRC 82, 044604 (2010).

K. Nishio et al., PRC 82, 024611 (2010).

1.8 pb 67 pb 0.54 pb 10 pb

283,282Cn

Ec.m. (MeV)

Pfu

s

48Ca+238U40Ca+238U

180 200 220 240

10-2

10-1

100

48Ca+238U (MeV)E*

20 30 40 50 60 70 80 90

40Ca+238U40 50 60 70 80 90 100 110

Fusi

on

Pro

bab

ility

Ec.m.

Fusion Probabilities for 48Ca + 238U and 40Ca + 238U

K. Nishio et al., Phys. Rev. C 86, 034608 (2012).

Fragment Mass (u)

Yie

ld (

%)

48Ca + 238U

S. Hofmann et al., Eur.Phys.J. A 32, 251 (2007).

Yu.Ts. Oganessian et al., Phys.Rev.C 70, 064609 (2004)

Yu.Ts. Oganessian, J.Phys.G 34, R165 (2007).

Capture cross section

Fusion Cross section

282,283Cn cross sections from

Cro

ss S

ection (m

b)

Ec.m. (MeV)

3n2n

4n

E* (MeV)

3n : FLNR4n : FLNR3n : GSI

CaptureFusion

48Ca +238U

170 180 190 200 21010-11

10-10

10-9

10-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

101

102

103 20 30 40 50

Summary

In beam fission experiment can be used to estimate the fusion

probability for heavy-element synthesis.

Model calculation in heavy-ion induced fission was shown.

Sub-barrier fusion reaction can be used for heavy-element

synthesis.

Heavy-Ion Program at J-PARC

J-PARC HI

JPARC HI

Heavy Ion LINAC (35m)

-13 MeV/u, 238U 238U 10-15 GeV/u

Proton 400 MeV 50 GeV

3 GeV

hadron

n, μ

ν

28

Heavy-Ion Acceleration at J-PARC

28

J-PARC

SPS

ALICE/PHENIX

STAR, energy scan

NICA

FAIR

QCD Phase diagram -search for critical point and

phase boundary-

New LINAC

RCS

MR

Ion Source

RFQ

• 108MHz

• Einj ~ 50keV

n×IH-DTL

• 108MHz

• 2~3m

• n~7

Short Cavities

• 324MHz

• Energy

tunable

RCS

Multi-turn injection

MR

197Au32+ 197Au79+

12.8MeV/u 188MeV/u 11.5GeV/u

- Laser Ion

Source

- EBIS

- SC-ECR

Full strip Linac

Three Extreme Region on Chart of Nuclei Z

N

N=Z

50

100

50

100 150 200 28

50 82

126

20 28

50

82

150

184

120 114

N=126

SHE

Search for Heaviest N=Z Nuclei

Search for Super-heavy Nuclei

Search for Heaviest N=126 Nuclei

Protons

Neu

trons

238U + 248Cm ( 6MeV/u )

238U

248Cm

Search for Super-Heavy Nuclei

by V. Zagrebaev (FLNR)