Ds and Its Decay Productstan11.jinr.ru/pdf/08_Sep/S_2/03_Ackermann.pdf30 35 40 45 50 12.7.2004),2 ,2...

Dieter Ackermann Sochi, September 8th 2011

270Ds and Its Decay Products

– Decay Properties and Experimental Masses

Dieter Ackermann

GSI Helmholtzzentrum für Schwerionenforschung GmbH

Sochi, September 8th 2011


Nuclear Structure Studies at SHIP - Status Overview

discoverd at SHIP

new or improved decay data

or X-rays measured

new isomeric states discovered

outline • decay spectroscopy @ SHIP

• K-isomers – two examples (252,254No)

• new results for 270Ds from second experiment in 2010


• isomer surviving separation

• emission after decay

• CE for highly converted transitions + X-ray emission

emission

emission

CE emission

emission

evaporation residue after separation

x-ray emission

Nuclear Structure of SHE - Decay Spectroscopy at SHIP/TASCA


high eff.

15%

(e.g. SHIP,

TASCA...)

• inclusive measurement • ER, 's, 's and e-

• clean • particle discrimination • ER- - correlations

• highly efficient • close geometry • stopped source

40 60 80 100 120 140 160 180 200 220 240 260 280 300 320

0

5

10

15

20

25

30

35

40

45

50

12.7.2004

(86,2

+-

0,3

)

143,3

+-

0,2

203,6

+-

0,2

co

un

ts

E / keV

- spectrum

in coincidence

to 255Rf -decay

F.P. Heßberger et al, EPJ A 30, 561 (2006)

Nuclear Structure of SHE - Decay Spectroscopy at SHIP/TASCA


184

162

126

152

neutrons protons

82

114

100 102

142

134 96

108

Nuclear Structure of Heavy Nuclei - Single Particle Levels and Deformation


184

162

126

152

neutrons protons

82

114

100 102

96 142

134

108

9/2-[734]

j15/2

d5/2

1/2+[631]

7/2-[514]

h9/2

f5/2

1/2-[521]

f7/2

7/2+[633]

i13/2 3/2-[521]

g9/2

7/2+[624]

Nuclear Structure of Heavy Nuclei - Single Particle Levels and Deformation


Nuclear Structure of the Heaviest Nuclei: - Production Rates

reaction σ/nbarn Ibeam/pμA countrate . 208Pb(48Ca,2n)254No 2000 1 15000 /h (at RITU/Jyväskylä 200 /h) 206Pb(48Ca,2n)252No 430 1 3300 /h 206Pb(48Ca,3n)251No 25 1 200 /h 209Bi(40Ar,2n)247Md 7 3 80 /h 208Pb(54Cr,1n)261Sg 2 1 15 /h 207Pb(64Ni,1n)270Ds 0.013 0.5 1 /d


13 cases: even-even: 10 even-odd: 2 odd-even: 1 Sg and Hs isotopes? T1/2: 70 ns (256Fm) – 1.92 s (250Fm) E*: 1-1.5 MeV (2.5 MeV for 254m2No)

270mDs T= ms

270g.s.Ds T= s

2.8

2.20.6140

40100

K-isomers for Z = 96 - 110 - Experimental Information


0 100 200 300 400 5000

50

100

150

200

Co

un

ts

t (ms)

T1/2

=101.2 ± 13.9 ms

206Pb(48Ca,2n)252No

0 50 100 150 200 700 750 800 850 900 950

0

50

100

150

200

250

No252iso

F.P.Heßberger 8.6.2006

K (

+ 1

23 ?

)

156

133

687

107 (

4+

-->

2+

) (lin

e d

uble

tt)

167 (

6+

-->

4+

)

224 (

8+

-->

6+

)

(evtl. diff. lifetim

e)

710

828

862

882

911

920

Co

un

ts

E / keVB. Sulignano et al. EPJ A33, 327 (2007)

B. Sulignano, PHD thesis, Universität Mainz, 2007

Nuclear Structure of the Heaviest Nuclei: - Isomeric states: 252No


208Pb(48Ca,2n)254No

25 50 75 100 125 150 175 200 225 250

0

20

40

60

80

250 275 300 325 350 375 400 425 450 475 500

0

5

10

15

20

25

500 525 550 575 600 625 650 675 700 725 750

0

10

20

30

40

50

60

No254m2_clo_einzel_r229_r2479.5.2007

E / keV

Ere

ign

isse

Ere

ign

isse

179.5

Ere

ign

isse

168.5

156.9

111.4

147.5

143.6

133.3

347.1

325.5

311.9

301.8

605.7

R.D. Herzberg et al.,

Nature 442, 896 (2006);

S.K. Tandel et al.,

Phys. Rev. Lett. 97, 082502 (2006)

F.P. Heßberger et al.,

Eur. Phys. J. A 43, 55-66 (2010)

Nuclear Structure of the Heaviest Nuclei: - Isomeric states: 254No


270Ds 266Hs (6 chains) chain# 1, 3 and 5 chain# 2

chain# 8 chain# 7

Theory:

rotational levels: A. Sobiczewski et al.

K-isomers S. Cwiok et al.

Experiment:

S. Hofmann et al.

266Hs 262Sg (8 chains) chain# 1-8 262Sg decay (8 chains)

chain# 1-8

8+

6+

270Ds and its Decay Products - 1st experiment in 2000 (S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)


162

[725]11/2-

[615]9/2+

[613]7/2+

1.34 MeV I = 10-

162

[725]11/2-

[615]9/2+

[613]7/2+

1.31 MeV I = 9-

neutrons

162

[725]11/2-

[615]9/2+

[613]7/2+

g.s.

Fermi

level

S. Cwiok, et al. HFB 2

117252

7613

270Ds: Z=110 N= 160

211725

29615

K-isomer in 270Ds - Theory Predictions: quasi particle excitation


-3 -2 -1 0 1 2 3

72

74

76

78

80

82

84

86

88

90

92

Me

an

tim

e o

f fli

gh

t /

s

Excitation frequency / Hz - 850012

253No

2+

-200

-150

-100

-50

0

50

253No252

No

MS

HIP

TR

AP-M

AM

E / k

eV

SHIPTRAP

AME'03

254No

SHIPTRAP August 2008

?

Decay Chain of 270Ds from 64Ni+207Pb - Results from October 2000 and Possible Extension


Observed types of decay chains I - ER-α-α-sf

a) ER-α-α-sf

15 chains


270Ds - 270Ds α-decay

• 26 decay chains (270Ds: 25, 271Ds:1)

• new spectroscopic data

* T1/2 from S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)

*


Observed types of decay chains II - ER-α-sf

a) ER-α-α-sf b) ER-α-sf

15 chains 8 chains

sf(266Hs) = 32%


270Ds - 266Hs sf-branch

new fission branch

in 266Hs




*

*


Observed types of decay chains III - ER-α-α-α-sf

a) ER-α-α-sf b) ER-α-sf c) ER-α-α-α-sf

15 chains 8 chains

sf(266Hs) = 32%

2 chains

α(262Sg) = 8%


270Ds - News III – 262Sg α-branch link to 254No



80

90

100

110

120

130

140

102 104 106 108 110

-1

0

1

2

270Ds

266Hs

262Sg

258Rf

254No

mc

2 /

Me

V

Möller-Nix

Liran-Zeldes

Myers-Swiatecki

Smolanczuk-Sobiczewski

Atomic Number

(m

c2(e

xp

)-

mc

2(t

heo

)) /

MeV

new fission branch

in 266Hs

α-decay link 262Sg 258Rf


*

*

*

J. M. GATES et al. PRC 77, 034603 (2008)


0,01 0,1 1 10 100

270Ds

266Hs

262Sg

Experiment 2000

Experiment 2010

270m

Ds ms

270gs

Ds ms

266

Hs ms

266

Hs ms

266

Hs ms

262

Rf ms

262

Sg ms

decay time [ms]

258Rf

0,01 0,1 1 10 100

270Ds

266Hs

262Sg

Experiment 2000

Experiment 2010

270m

Ds ms

270gs

Ds ms

266

Hs ms

266

Hs ms

266

Hs ms

262

Rf ms

262

Sg ms

decay time [ms]

258Rf

Decay details

- time distributions

Run 197 - experiment 2000 Run282 - experiment 2010

105 ms

Decay chain 8

266

Hs

270

Ds

262

Sg

271

Ds

10.968 MeV

5.31 ms

180 MeV + ?

6,239 ms

10.440 MeV

104,66 ms


270Ds Decay Scheme

270Ds:

13 g.s. decays - 2 γ‘s: 175/741 keV 12 isomer decays - 1 γ: 1094 keV (in 2000: 3:3 + 1 γ)

chain 8: Eα 200-300 keV lower

266Hs: 16 g.s. decays 1 isomer decay with a 332 keV γ-ray

chain 8: Eα 200 keV higher Ev = 332 keV

262Sg: α decay observed for the first time (1 full E, 1 escape)

332 kev

Calculations: HFB: S. Cwiok, et al. PES: F.R. Xu, et al. PRL 92, 252501 (2004) TCSM: G.G. Adamian et al., PRC 81, 024320 (2010)

8+

9-

10-

10+ 9-

8+

9- 10-

10+ 8+

6+ 7- 4- 9-

9-

10- 10-

6- 8+

6+ 10-

9-

10- 8+ 6+

7-

9- 10-

7- 6+ 4+ 5+ 5-


ground state, decay and structure properties up to Z=110 • α-γ coincidences (total: 4)

• fission branch in 266Hs

• experimental mass for 270Ds

• new K-isomer 266 Hs

Summary - Achievements


• nuclear structure studies single particle states/level density gap

• reaction mechanism systematics (transfer, fission, incomplete fusion, spin distribution, ...)

• efficiency upgrade DC accelerator

• mass measurement Ebind

• mass determination (A(Z) identification) new separator/spectrometer

• employment of all available technology and methods (ER-α-γ correlations, chemistry, traps, mass determination, ...)

“rare isotopes”? yes for systematic investigations maybe(???) for SHE synthesis (low beam intensity!!!)

localisation of the region of spherical shell-stabilized SHE

beam

beam separator

(e.g. velocity filter)

M/q spectrometer

particle and phonon

detection array

• efficient beam separation • high transmission • M/q separation • highly efficient particle and photon detection

New M/q spectrometer – separator for SHE

target Possible Solution:

S3

@

SHE Synthesis and Nuclear Structure of SHE - Roadmap/Long Term

Possible GSI

acc. schemes:

HSI IH Stripper CH

SIS 18

HSI IH Stripper CH

SIS 18

HSI IH Stripper CH

SIS 18

HSI IH Stripper CH

SIS 18

HSI IH Stripper CH

SIS 18

high charge cw-injector

high charge cw-injector

material science/ISL

SHIP

TASCA X1

SHIP

TASCA X1

ISL

HSI

HSI

cw

warm

cw cold

UNILAC

SIS ECR 1

ECR 2 MUCIS

MEVVA

Penning

SHE Exp.


D.A., M. Block, H.G. Burkhard, Ch. Dröse, M. Dworschak, F.P. Heßberger, S. Hofmann, W. Hartmann, A. Hübner,

B. Kindler, J. Khuyagbaatar*, I. Kojouharov, B. Lommel, R. Mann, J. Maurer, E. Minaya, J. Steiner, B. Sulignano** Gesellschaft für Schwerionenforschung (GSI)

D-64220 Darmstadt, Germany

A.G. Popeko, A.V. Yeremin Flerov Laboratory of Nuclear Reactions, JINR

Ru-141 980 Dubna, Russia

S. Antalic, S. Šaro, M. Venhart Department of Nuclear Physics,

Comenius University

SK-84248 Bratislava, Slovakia

M. Leino, J. Uusitalo Department of Physics, University of Jyväskylä

FIN-40351 Jyväskylä, Finland

V.F. Comas, J.A. Heredia Higher Inst. of Technologies and Appl. Sciences Havana 10600, Cuba

K. Nishio Japan Atomic Energy Research Institute

Tokai, Ibaraki 319-1195, Japan

R. Dressler Paul-Scherrer Institute (PSI)

5232 Villigen, Switzerland

* also university of St. Petersburg, Russia ** now CEA Saclay, France

The SHIP Collaboration

photograph by Gabi Otto


The ECOS Network Activity in the ENSAR framework of the EU FP7 program has among others with its Task 2 the objective to promote synergies in the field of Super-Heavy Element (SHE) research, described as follows: "For this task ECOS is aiming for bringing together the groups with research activities on SHE using high-intensity ion beams for an exchange of new ideas and techniques related to the use of very high intensity stable beams. In particular, Task 2 will propose an optimisation of resources (beam time, target technology, detectors) in the field of SHE research among TNA facilities." The ENSAR-ECOS Workshop on FUture Super-Heavy Element Strategy – FUSHE 2012 is one very important milestone in this process. It will provide a forum for the SHE community to discuss and define the future strategy to reach the common goal – the establishment and investigation of the region of spherical shell-stabilised super-heavy nuclei – the so called “Island of Stability”.


FUSHE 2012 - Venue

The Conference&Sports Hotel Erbismühle is located in a nice valley, the Weiltal, in the Taunus hills about 50 km north of Frankfurt (50 km to Frankfurt main station and 55 km to Frankfurt airport) close to the village Weilrod in the centre of Germany. 72 rooms €90 (€60 double occupation) + interesting food option The Taunus hills have formed the northern border of the Roman Empire and traces of it can still be visited today like the rebuilt Roman Castle Saalburg together with a few meters of the limes, the Roman border installations and defence line against the barbarians north of it…


FUSHE 2012 - Contact

Dieter Ackermann (Chair): [email protected] David Boilley (Co-chair): [email protected] Christelle Stodel (Scientific secretary): [email protected] Secretaries: Ms. Siglind Raiß: [email protected] Tel.: +49-6159-71-2412 Ms. Tatjana Litvinova: [email protected] Tel.: +49-6159-71-2127 Fax: +49-6159-71-2902.

Workshop email address: [email protected] Webpage: http://www.ensarfp7.eu/workshops/fushe2012/

mailto:[email protected]






http://www.ensarfp7.eu/workshops/fushe2012/

Ds and Its Decay Productstan11.jinr.ru/pdf/08_Sep/S_2/03_Ackermann.pdf30 35 40 45 50 12.7.2004),2 ,2...

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