106 th session of the jinr scientific council september 24-25, 2009, dubna perspectives of jinr –...

106th Session of the JINR Scientific Council September 24-25, 2009, Dubna

Perspectives of JINR – ORNL Collaboration in the Studies of

Superheavy Elements

For JINR: Yu.Oganessian

http://asrc.tokai-sc.jaea.go.jp/java_top.html

1.Short Introduction

2.The “Island of Stability” of SHE

3.Test of nuclear models

4.Beyond the Periodic Table

5.Setting of the Z=117-experiment

6.Our efforts

CONTENT

Pro

ton

nu

mb

er 120

110

100

90

80

70

LogT (seconds)

1/2

14

-2

6

10

2

100 110 120 130 140 150 160 170 180 190Neutron num ber

-6126

82

StableElements

208Pb

114

184

SuperheavyElements

TransuraniumElements

cold fusionabout 25 years

Act+ 48Cafrom 2000

Yu.Oganessian. Perspectives of JINR – ORNL Collaboration in the studies of SHE. JINR Scientific Council, Sept 24-25. 2009, Dubna

48C a-ions

rota ting en trancew indow

gas-filledcham ber

de tecto rsta tion

recoils

position sensitivestrip detectors

TO F-de tecto rs

“ve to” detecto rs

22 .50

S H recoil

s ide de tecto rs

Gas-Filled Recoil Separator

Transmission for: EVR 35-40% target-like 10-4-10-7

projectile-like 1015-1017

Registration efficiency: for α-particles 87% for SF single fragment 100% two fragments ≈ 40%

Targets:Isotopes of U, Pu, Am, Cm and Cf (now Bk)

Beam:48Ca

Experimental technique

Act. + 48Ca

Targetmaterials

producer Isotopeenrichment (%)

233U IAR 99.97

238U — 99.3

237Np IAR 99.3

242Pu IAR 99.98

244Pu ORNL 98.6

243Am IAR / ORNL 99.9

245Cm IAR 98.7

248Cm ORNL / IAR 97.4

249Bk ORNL ≥ 95

249Cf ORNL / IAR 97.3

Projectiles 48Ca produced byHeavy Ion Accelerator U - 400

Energy: 235-250 MeV

Intensity: 1.0-1.5 pμA

Consumption: 0.5-0.8 mg/h

Beam dose: (0.3-3.0)∙1019

Reactions of SynthesisReactions of Synthesis

115/287

10.59

3 ms2

113/283

10.12

0. s1

111/279

10.37

0.17 s

109/2 57

10.33

9.7 ms

107/2 17

105/267

1.2 h

a

a

a

a

a

109/276

9.71

0.72 s

107/272

9.02

9.8 s

113/284

10.00

0.48 s

115/288

10.46

87 ms

105/268

1.2 d

111/280

9.75

3 6. s

104/268

a

a

a

a

a

243Am242Pu, 245Cm

226Ra

Sg/266

0.2 s

Hs/270

10 s

9.06

aσ4n≈10pb

237Np

244Pu, 248Cm249Cf

DecaychainsDecaychains

34 nuclides

48Ca +

T1/2= 320d

164

104/270

105/270

107/274

109/278

111/282

113/286

115/290

117/294

103/266

102/266

107/273

109/277

105/269

111/281

113/285

115/289

117/293

104/269

249Bk

+48Ca

2009-2010

Collaboration: FLNR (Dubna) ORNL (Oak-Ridge) LLNL (Livermore)IAR (Dmitrovgrad)Vanderbilt University (Nashville)

Decay Properties of SH- nuclei

12.0

11 .0

10 .0

110

112

Z -even

T heory :

114

116

118

108

106

9.0

8.0

7.0260 270 280 2 09 300

A tom ic m ass num ber

Alp

ha d

eca

y en

erg

y (M

eV)

Z -even

E xp:


-6

-8

-4

-2

0

2

4

6

8

10

12

14

16

18

Z=112

112

114110

106

Sg

Rf

No

Cf

N=152

N 6=1 2

N 5=1 2N 84=1

Fm

140 145 150 155 160 165 170 175 180 185N eu tron num ber

Log

T

(s)

SF

Exp.

Theory

H sD s112114

S gR fC f-N o

Spontaneous fission half-livesSpontaneous fission half-lives

Actinides

Trans-actinides Superheavy nuclei

155

N eutron num ber

Hal

f-lif

e, T

(s)

a

160

SF

SF

165 170 175

118

116

114

112110

111

113

115

18010 -6

10 -4

10 -2

100

102

10 4

Half lives of nuclei with

Z ≥ 110

N=162

Half lives Act. + 48Ca

With Z >40% larger than that of Bi, the heaviest stable element, that is an impressive extension in nuclear survival.

Although the SHN are at the limits of Coulomb stability, shell stabilization lowers: the ground-state energy, creates a fission barrier, and thereby enables the SHN to exist.

The fundamentals of the modern theory concerning the mass limits of nuclear matter have been verified experimentally for the first time


Element 120

Test of nuclear modelsTest of nuclear models

N=184

N=184

Z=114

Z=124Z=124

N=184

Z=120-122Z=120-122

N=184

Z=114

MMM

HFB

RMF

Microscopic theory and the properties of heaviest nuclei

Microscopic theory and the properties of heaviest nuclei

13.0

12.0

11.0

10.0

9.0

-5 5 10-10-15-20 0

N-N SHELL

th:HFB MMM

Alp

ha

dec

ay e

ner

gy

(MeV

)

116(exp)

13.0

14.0

12.0

11.0

10.0

9.0

Alp

ha

de

cay

en

erg

y (

Me

V)

-5 5 10-10-15-20 0N-N

SHELL

HFB

M M M

298,299120 EVR

3μs

0.03s

Z=116Z=120


3n

251Cf (α/898y)

S F ~ 90 %

1a

2a+32-9

10 .7 4 M eV

114

120

N = 18 2

118

299

295

10 .0 3 M eV +1 .3-0 .4

9 .55 M eV

+8 .3-2 .5

a

a

110

279

112

283

3a

116

291

3a

a

116

290 11 .65 M e V

0 .89 m s+1 .07-0 .31

1a

112

282

10 .8 4 M eV

7 .1 m s +3 .2-1 .7

10 .1 9 M eV

0 .13 s

+0 .04-0 .02

S F

2a

20 5 M eV

118

294

114

286

a

3n

1a

2a 26 m s

114

120

118

287

299

295

1 .1 s

7 .0 s+8 .3-2 .5

a

a

110

279

112

283

3a

116

291

3a

a

116

290

1a

112

282

0 .13 s

-0 .02

2a

118

294

114

286

a

4n

CN

120

302

120

298

120

298

238U + 64Ni GSI 2008244Pu + 58Fe FLNR 2007248Cm + 54Cr GSI 2010

252Cf + 50Ti(α,SF/2.6y)

Cold fusion cross sections and fusion probabilityCold fusion cross sections and fusion probability

10-30

10-32

10-34

10-36

10-38

102 104 106 108 110 112 114 116 118

A tom ic num ber

Cro

ss s

ectio

ns

(cm

)2

208 209 48P b, B i + C a

Z n70 N i

64 F e

58 C r

54

T i

5010-30

10-32

10-34

10-36

10-38

102 104 106 108 110 112 114 116 118

A tom ic num ber

Cro

ss s

ectio

ns

(cm

)2

K . M orita et al., J. Phys. Soc. Jpn, (2004) 2593.

S. Hofm annRep. Prog. Phys., 61 (1998) 639

208 209 48P b, B i + C a

Z n70 N i

64 F e

58 C r

54

T i

50

150 200

100

10-2

10-4

10-6

10-8

Coulomb repulsion

Fu

sion

pro

bab

ility

15010050

Z .Z / A +A1 21/3 1/3

200 250 300

208 16P Ob +

48Ca

1 event / year

SHE

Ex=12-15 MeVCold fusion

Act.+48Ca

Z=112-118Z=112-118

249Bk+48Ca

251Cf+50Ti

248Cm+54Cr

244Pu+58Fe238U+64Ni

~ 0.05-0.1pb


Beyond the Periodic Table

H

1

Li

3

Be

4

Na

11

M g

12

K

19

Ca

20

Sc

21

104

Ti

22

V

23

Cr

24

M n

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

1

2

3 4 6 7 8 9 10 11 12

13 14 15 16 17

18

1

2

3

4

5

6

He

B

Al Si P S

ONC F

Cl Ar

Ne

7105 106 107 108 109 110 111 112 113 115114 116 117 118

72 74 75 76 77 78 79 80 81 82 83 84 85 8655 56

87 88

37 38 39 40 42 43 44 45 46 47 48 49 50 51 52 53 54

31 32 33 34 35 36

Rf Db Sg Bh Hs M t

Rb Sr Y Zr M oNb Tc Ru Rh Pd Ag Cd In Sn Sb Tc I Xe

Cs Ba Hf WTa Re O s Ir Pt Au Hg Ti Pb Bi Po At Rn

Fr Ra

G a G e As Se Br Kr

Da

rms-

tad

tiu

m

Ds Rg

ChemicalpropertiesChemicalproperties

82

Pb

50

Sn

14

1 10

Ds

12

112 114

Ca

20

Pu

94

Rn

relativisticrelativistic

Ch

emic

al is

ola

tio

n

80

Hg

48

Cd

86

Reaction:

242Pu(48Ca,3n)287114[0.5s]→α→283112[3.6s]

R. Eichler et al., Nature 447 (2007) 72 Compound Hg(Au)

and 112(Au)

Compound Hg(Au)

and 112(Au)

1a

2a

114

112

287

283 10.02 MeV 0.5 s

9.54 MeV 3.8 s

0.2 s TKE=225MeVSF

110281

2a 112283

9.54 MeV

0.2 s SF

110281

1a

2a

114

112

287

283 10.04 MeV

9.53 MeV 10.9 s

0.24 s TKE= 220MeVSF

110281

Element 112 is a noble metal – like Hg

room temperature


7s

6s

5s

5d

4d4s3s2s

5fr max

rel /r

max

non-

rel

4f

Relativistic Contraction

non-

relativistic

7s

6s

5s

5d

4d4s3s2s

5f

4f

0,80

0,75

0,85

0,90

0,95

1,00

1,05

7s

6s

5s

6p5p4p

5d

4d

3p

4s3s2s

5f

0 20 40 60 80 100 120Z

1s 2p3d

4f

rm ax : principal maximum of the wave function of the outermost orbital

J.P. Desclaux, At. Data Nucl. Data Tables 12 , 311 (1973)J.P. Desclaux, At. Data . Data Tables 12 , 311 (1973)J.P. Desclaux, At. Data . Data Tables 12 , 311 (1973)

-

relativistic

Atomic propertiesAtomic properties

HgPb

~ Z2 113 critical

SHE

112114

more and more inert?

H

1

Li

3

Be

4

Na

11

M g

12

K

19

Ca

20

Sc

21

104

Ti

22

V

23

Cr

24

M n

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

1

2

3 4 6 7 8 9 10 11 12

13 14 15 16 17

18

1

2

3

4

5

6

He

B

Al Si P S

ONC F

Cl Ar

Ne

7105 106 107 108 109 110 111 112 113 115114 116 117 118

72 74 75 76 77 78 79 80 81 82 83 84 85 8655 56

87 88

37 38 39 40 42 43 44 45 46 47 48 49 50 51 52 53 54

31 32 33 34 35 36

Rf Db Sg Bh Hs M t



Fr Ra

G a G e As Se Br Kr

Dar

ms-

tad

tiu

m

Ds Rg

5

73

41

?

Periodic Table of ElementsPeriodic Table of Elements

114 115

115

117

a

a

249Bk(320d) + 48Ca

243Am(7370y) + 48Ca


113 113 113 113 113

115 115 115

117

278 282 283 284 286

287 288 290

294

Isotopes of Element 113

209Bi + 70Zn

RIKEN (Tokyo)

0.24ms

σ =0.03pb

243Am + 48Ca

237Np + 48Ca

243Am + 48Ca

half-life

JINR (Dubna) - - LLNL (Livermore) - - ORNL (Oak-Ridge) collaboration

0.07s 0.5s 10s

σ =4.2pb


rotatingtarget

entrancewindow

beam

beam

RECOILS q=q eq

pumping

pumping

acceleratio

n

RF

RF+ERF

q=1+ He

H 2+B

stopping

volume

E

separatingwindow

GAS CATCHERGAS CATCHER

Guy Savardfrom Argonne National Laboratory

beam of high quality Δt =

20-50 ms

transm

ission ≈ 50%

Mass Analyzer of Super Heavy Atoms

(MASHA)

Transmission for Hg-atoms ≈ 75%

Mass measurements

gascatcher

intermediate focu

s Position of the detector array

magnetic deflection

electrostaticdeflection

M / M 3500

8119

121

120? ?

?

121 122 123 135

H

1

Li

3

Be

4

Na

11

M g

12

K

19

Ca

20

Sc

21

104

Ti

22

V

23

Cr

24

M n

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

1

2

3 4 6 7 8 9 10 11 12

13 14 15 16 17

18

1

2

3

4

5

6

He

B

Al Si P S

ONC F

Cl Ar

Ne

7105 106 107 108 109 110 111 112 113 115114 116 117 118

72 74 75 76 77 78 79 80 81 82 83 84 85 8655 56

87 88

37 38 39 40 42 43 44 45 46 47 48 49 50 51 52 53 54

31 32 33 34 35 36

Rf Db Sg Bh Hs M t



Fr Ra

G a G e As Se Br Kr

Dar

ms-

tad

tiu

m

Ds Rg

5

73

41

?

Periodic Table of ElementsPeriodic Table of Elements

251Cf + 48Ca

3ms118

254Es + 48Ca

1ms119

Setting an Experiment on the Synthesis of Setting an Experiment on the Synthesis of

Element 117

Reaction: 249Bk + 48Ca → 297117* → 294-293117 + 3-4n

T1/2=320d

high intensity of 48Ca beam (~1.5 pμA)U- 400 FLNR, JINR

Separation, Detection & Identification

1 SH-atom / 1012 reaction products

DGFRSDubna Gas-filled Recoil Separator

high neutron fluxHIFR, ORNL

chemical separation

from 252Cf (factor 1011)

target preparation 36cm2

0.25 μm BkO2+ 1.6 μmTi

IAR, Dimitrovgrad


22 mg of 249Bk have been produced with neutrons of HIFR ORNL

293 294

290289

117

2 9 7

117

115

11. 00 M eV11. 27 M eV

249Bk + Ca 48

0. 03 s7. 0 ms

10. 22 M eV0. 7 s

10. 48 M eV0. 15 s

270269

105

266265

103103

3n4n

286

282

278

274

285

281

277

273

113

111

109

107

11 s0. 84 s

286

282

278

274

285

281

277

273

113

111

109

107

9. 55 MeV9. 95 MeV

9. 43 MeV10. 13 M eV

9. 14 MeV9. 60 MeV

5. 6 s0. 04 s

8. 8 s0. 42 s

8. 42 MeV8. 65 MeV5. 1 min55 s

Expected decay chain of the isotopes of element 117

A. Sobiczewski 10/24.03.09

270

274

269

105

107

7.71 MeV

8.42 MeV

7.94 MeV

6.55 MeV6.41 MeV

4.8h

5.1min

0.7h

SF5.9y27y

266265

266

103103

102

1000 .1

1 .0

10

100

1000

10000

105A tom ic num ber

208 226 233,238 249 48P b, R a , U ... C f + C a

xn -

cro

ss s

ect

ion

(p

b)

N o

H s

S H E

110 115 120

Cross sections

117

249Bk + 48Ca

U -400 & D G FR S

N ew type D G FR S

N ew A cce lera tor

U pgrade of U -400

2009 2010 2011 2012 2013 2014 2015 2016

E xperim enta l ha ll

Z=117

2.5p A

10p A

1m g/cm +gas catcher2

new physics

1

2.5

5.0

20

Gain factors for production of Super-heavy nuclei

In theory: from macroscopic(liquid drop)

to microscopic(microscopic

models)

Checking models

In accelerators

from light ions12C- 16O

to massive one48Ca-136Xe

new cyclotrons, ECR sources, etc

to higherintensity

new acceleratorors

In method: from slow techniques

wheels, He-jet

to fast in-flight separators

recoil separators

to on-lineseparator

gas catcher

In the sensitivity:

from the cross sections

≥ 10,000pb

to the cross sections≥ 0,5pb

to the cross sections≥ 0,05pb

In the chemistry:

from Actinides to Trans-Actinides to Superhavy Elements

All these tasks took us about 40 years

Now we would like to have it in 6 years!

In order to understand the limits in the existence of the elements we had to move:

Thanks for your attention

Cross sections

117

Tads 100 0 100 C

Hg 112rel 112nrRnLocalized

adsorption

(gold):

Mobile adsorption

(quartz):

Tads of Hg and Element 112 on Quartz and Gold

Tads 100 0 100 C

V. Pershina 2006

Predictions

Exp.2007

Quartz

Gold

106 th session of the jinr scientific council september 24-25, 2009, dubna perspectives of jinr –...

Documents

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nuclear survival

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