Experiments with Stored Exotic Nuclei at Relativistic Energies The Experimental Facility Mass...

Experiments with Stored Exotic Nuclei at Relativistic Energies

The Experimental Facility

Mass measurements

Lifetime measurements

Future

Hans Geissel, Y. Litvinov, GSI and JLU GiessenJapanese-German Nuclear Structure and Astrophysics Workshop

Dec. 16-18, 2004

Hans Geissel, Japanese-German Workshop

The Team

F. Attallaha, K. Beckerta, P. Bellera , F. Boscha, D. Boutina, M. Falchc, T. Fästermannf, B. Franczaka, B. Franzkea, Y. Fujita, H. Geissela,d, M. Hausmanna, M. Hellströma , E. Kazaa, Th. Kerscherc, O. Kleppera, H.-J. Klugea, C. Kozhuharova,

K.L. Kratze, K.E.G. Löbnerc, Yu.A. Litvinova,b, S. Litvinovb, M. Matoša, L. Maierf, G. Münzenberga,e, F. Noldena, Yu.N. Novikovb

T. Ohtsuboh, A. N. Ostrowskie, Z. Patykg, B. Pfeiffere, M. Portilloa, T. Radona, C. Scheidenbergera, J. Stadlmanna, M. Stecka, K. Sümmerera, D. Vieira,

H. Weicka, M. Winklera, H. Wollnikd, , T. Yamaguchia

Monoisotopic Fragment BeamsStored in the ESR

Experimental Facilities

S t o p p i n g P o w e r o f R e l a t i v i s t i c H e a v y I o n s

B r e a k - d o w n o f t h e r e l a t i v i s t i c B e t h e t h e o r y ,F R S e x p e r i m e n t a l r e s u l t s w e r e t h e m o t i v a t i o no f t h e n e w t h e o r e t i c a l d e v e l o p m e n t b y J . L i n d h a r da n d A . H . S o e r e n s e n

Precision Mass Measurements in the ESR

v 1

(m /q)0

(m /q)0

(m /q)1

v 1

(m /q)1

v 0

In jection

Septumv 0

TO F-D etector

Hot Fragments

Isochronous Mass Spectrometry

In jection

Septum

ElectronC ooler

(m /q)

(m /q)

(m /q)

(m /q)

>

>

>

SchottkyNoise-P ickups

Cooled Fragments

Schottky Mass Spectrometry

ff

vv

(m /q)m /q2

t= + 2

t

21 (1 )

t

vv

0

Precision Mass Measurements in the ESR

Detector for Isochronous Mass Measurements in the ESR

Carbon foil, ~20 g / cm2

CsI coating 10 g / cm2

diameter 40 mm

Magnetic field: 10 mT

Chevron arrangement of 2 MCPs diameter 40 mm


Schottky Mass Spectrometry950 MeV/u 209Bi + Be Projectile Fragments

New and Reference Masses in the same Spectrum

High Resolution

and Sensitivityaccuracy: 30 keV

Proof of Single Atoms Stored in the ESR

frequency [Hz]

no

ise

po

wer

den

sity

a.u

.

Yu. Litvinov


Accuracy of Schottky Mass Measurements

80 100 120 140 160 180 200

2 10

Mass Number

. -7

4 10. -7

6 10. -7

8 10. -7

1 10. -6

Ma

ss A

ccu

racy

SMS 1995

SMS 1997

T. Radon, Yu. Litvinov

σ = 30 keVSMS 2003


Comparison to ISOLTRAPYu. Litvinov

J. Dilling, PHD Thesis, Heidelberg, 2001 F. Ames et al., Nucl. Phys. A651, 3 (1999)

S. Schwarz et al., Nucl. Phys. A693, 533 (1999) A. Kohl, PHD Thesis, Heidelberg, 1999


Results compared with Theory

rms = 650 keV

S. Goriely et al.

PR C66 2002


Predictive Power of the Relativistic Mean Field Model (RMF)

rms = 3831 keV

G.A. Lalazissis et al. ADNDT 71 (1999)1even-even nuclei, NL3, rms

= 2.6 MeV

Yu. Litvinov


Isospin Dependence of Pairing

2. Pairing-Gap energy, deduced from 5-point binding difference

25n c)2N,Z(m)1N,Z(m4)N,Z(m6)1N,Z(4)2N,Z(m

8

1

25p c)N,2Z(m)N,1Z(m4)N,Z(m6)N,1Z(4)N,2Z(m

8

1


New Mass Values compared with Theory

Yu. Litvinov

M. Matos

Preliminary238U

Fission

Fragments

209Bi

Projectile

Fragments


Lifetime Measurements of Short-lived Nuclei Applying Stochastic and Electronic Cooling

207mTl81+

207Tl81+

207Pb81+

Bound-state Beta-Decay of 207Tl81+

207Pb81+

207Tl81+

207mTl81+


Combination ofstochastic and electron cooling

D. Boutin82000 101500 121000 140500 160000 179500 199000 218500 238000

Frequency - 61050000 [Hz]

0.105 s

1.05 s

2.10 s

3.15 s

4.19 s

5.24 s

6.29 s

Tim

e a

fter

inje

ctio

n [s

]208 81+Pb 207 81+Tl/Pb

202 79+Hg

Sto

chastic + e

lectron coo

lingE

lectron

coolin

gS

tochastic C

oolingE

lectron C

ooling

202Pb81+ 202Hg79+ 207Tl81+


207 81+Tl

207 81+Pb207m 8 1+Tl

207m 8 1+Tl

207 81+Tl

207 81+Pb207m 8 1+Tl

207 81+Tl

207 81+Pb

207 81+Tl

207 81+Pb

207 81+Tl

207 81+Pb

207m 8 1+Tl

sT

Tlab

lab 11.049.12ln2/1

2/1

4305.1

D. Boutin, F. Nolden

Observation of the Short-Lived Isomer 207mTlwith Stochastic Cooling


Lifetime Measurements of 207mTl

Shorter cooling time allowed to see isomeric state of 207Tl (E* = 1348 keV, half-life of 1.33 ± 0.11 s for neutral atom)

Measured half-life of bare nuclei, transformed in the rest frame:

sT

Tlab

lab 11.049.12ln2/1

2/1

4305.1


Schottky Spectrum of Continuous andBound-State Beta Decay of 207Tl81+

= 1406 keV


Half-life Measurements of 207Tl81+ Bound-state Beta Decay

sΤNuc

/ 12542ln

21

01.016.0

cb

b

D. Boutin

Nuclear Decay of Stored Single Atoms

Time-resolved SMS is a powerful tool to study dynamical processes

Changes of half-lives of nuclear isomersin fully ionized atoms

Half-life of the isomeric state of 149mDy in neutral atom is 0.49(2) s

laboratory frame

Measured half-life in the fully ionized atom 149mDy is 11(1) s

Hindrance factor T1/2 (fully ionized)

T1/2 (neutral)= 22(2)

Yu. Litvinov et al. PL 2003

Mass Surface expected to be covered in the SMS experiment 2004

New K-Isomers in the 178 Lu region

RESR

CR

NESR

ELISe

Gas target

EXL

ILIMA

Super-FRS

Future

Experiments with Stored Exotic Nuclei at Relativistic Energies

Experiments with Stored Exotic Nuclei at Relativistic Energies The Experimental Facility Mass...

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