Frank HerfurthGSI, Darmstadt, Germany

for the ISOLTRAP Collaboration

Status report IS413:High-precision mass measurements of exotic nucleiwith the triple-trap mass spectrometer ISOLTRAP

INTC meeting, February 20, 2006

• Experiments and results 2005

• Technical developments

• Proposal 2006

ISOLTRAP collaboration:G. Audi, S. Baruah, D. Beck, K. Blaum, G. Bollen, M. Breitenfeldt, P. Delahaye,

M. Dworschak, S. George, C. Guénaut, U. Hager, F. Herfurth, A. Herlert,A. Kellerbauer, H.-J. Kluge, D. Lunney, M. Marie-Jeanne, M. Mukherjee,

S. Schwarz, L. Schweikhard, C. Weber, C. Yazidjian, ... ,

Funding and support:BMBF, GSI, CERN, ISOLDE,

EU networks EUROTRAPS, EXOTRAPS, NIPNET, EURONS

The Team

ISOLTRAP runs in 2005

ISOLTRAP program 2005

total number of shifts: 30

ISOLTRAP mass measurements in 2005

71-81Zn71-81Zn

Nuclides measuredin 2005

Nuclides measuredin 2005

118,120,122-124Cd118,120,122-124Cd

126Xe, 136Xe126Xe, 136Xe

127,128,131-134Sn127,128,131-134Sn

17Ne, 19Ne17Ne, 19Ne

first doublycharged ions

measured after report 2004

ISOLTRAP mass measurements in 2005

-10 -5 0 5 10

280

300

320

340

360

380

mea

n T

OF

/ µ

s

rf - 1122161.85 Hz / Hz

81Zn+

42 44 46 48 50 52

6

8

10

12

14

16

S

2n /

MeV

neutron number N

ISOLTRAP mass measurements in 2005

ISOLTRAPAME2003

Zn

preliminary

Two neutron separation energy for the zinc isotopes

Technical Developments

new detector

0 20 40 60 800

2

4

6

8

10

CEMMCP

Nu

mb

er

of

Ion

s p

er

Pu

lse

Time / ms

Technical Developments

Heater

Fan

temperaturesensor

• Temperature & pressure stabilization

• New test ion source

• All elements• Mass selective

Nuclides from P160 proposal

Proposed ISOLTRAP mass measurement program 2006

Proposed ISOLTRAP mass measurement program 2006

Need hydrogen as buffer gas, preparation required

3

Proposed ISOLTRAP mass measurement program 2006

Clean gas inlet for N2

Good HRS settingto remove CO contaminant

Proposed ISOLTRAP mass measurement program 2006

Also possible as off-linerun with existing target,high statistics needed

Proposed ISOLTRAP mass measurement program 2006

Additionally, in-trap decay provides access to mass measurements on Fe isotopes

Proposed ISOLTRAP mass measurement program 2006

For UC target with quartztransfer line clean conditions expected(as for Zn)

Proposed ISOLTRAP mass measurement program 2006

Fr and Ra highly contaminate the beam, no solution found so far.

• Successful measurements using 30 shifts in 5 runs (+2 incomplete) in 2005

• A number of technical improvements increase stability and efficiency

• 27 shifts in 5 runs of radioactive beam requested for 2006

• + 3 shifts to test the access to He isotopes

Summary