1. Lanzhou

2. Yellow River

3. Instutute of Modern Physics, CAS
Heavy-Ions based research center in China.
744 staffs，30～45 M $/y research budget.

4. Isochronous mass measurements of short-lived nuclides at CSRe
[RIBF-ULIC-Symposium-009] Physics of Rare-RI Ring, Nov. 2011, RIKEN
Isochronous mass measurements of short-lived nuclides at CSRe
Yu-Hu Zhang
Institute of Modern Physics, CAS
11 Nov , RIKEN, Japan

5. Outline Introduction Experiments at CSRe and data analysis
[RIBF-ULIC-Symposium-009] Physics of Rare-RI Ring, Nov. 2011, RIKEN
Outline
Introduction
Experiments at CSRe and data analysis
Results & Discussion
Summary

6. 1. Introduction Please refer to the invited talks of Klaus Blaum (MPI)
Meng WANG (CSNSM)
Hans Geissel (GSI)

7. 2. Experiments at CSRe and data analysis
Layout of HIRFL-CSR complex in IMP
SSC
SFC
CSRe
ECR
RIBLL2
RIBLL1
CSRm

8. ToF Principle of mass measurement in CSRe
Injection
Isochronous Mass Spectrometry (IMS mode)
Low production yield and short-lived nuclides.

9. Experiments at CSRe
78Kr + 9Be
Time detector
gt=1.395  368 MeV/u

10. Procedure of Data analysis
Ions Identification
Signals in Oscilloscope
Simultion.
Exp. P2

11. 78Kr beam: Revolution Time Spectrum
Nuclides for Calibration:
Unknown masses are determined via extropolation

12. 58Ni beam: Revolution Time Spectrum
Fe-49
V-43
Mn-47
Cu-55

13. Some techniques in the data analysis
1) Magnetic field drift
2) Amplitude-ion identification
3) Extrapolation
4) Interpolation

14. 1) Magnetic Field Drift (78Kr beam)
53Co g.s plus
53Co (3.2MeV isomer)

15. Ref.
Time Shift Correction
Ref.
Ref.

16. Corrected revolution time spectrum
GSI meth.
S 3 min.
No Correction
IMP meth.
m/∆m≈1.7x105
53Co isomer E*=3174.3(1.0)keV,(20ps difference)

17. Experiment: 58Ni beam Dec. 2010 Feb. 2011
Magnetic field stability was improved
Dec. 2010
Feb. 2011

18. 58Ni beam: Revolution Time Spectrum
Sum of 760 sub-spectra, each of which includes ~100 spills
34Ar, 51Co:
same m/q

19. 2) Ion-amplitude identification: 51Co

20. 3) Extrapolation (78Kr beam)
Nuclides for Calibration:

21. 4) Interpolation (58Ni beam)
Nuclides for Calibration:

22. 3. Results and Discussion
Tz=-1/2, ( 78Kr Beam)
Tz= -1, -3/2, ( 58Ni Beam)

23. Waiting point nucleus 64Ge ?

24. Waiting point nucleus 64Ge ?
Sp(65As) = -90 (85) keV 2s
Effective half-life of 64Ge
Light curve of Type I x-ray burst 1s
89%–90% of the reaction flow passes
through 64Ge via proton capture
indicating that:
64Ge is not a significant rp-process
waiting point.
Abundance of burst ashes

26. Precise mass data of astrophysics interest
43V
47Mn
65As
PRC79, (2009)

27. Q-values for the（p, g）reactions of astrophysics interest

28. Nuclear Physics：test CDE calculations

29. Nuclear Physics：test the mass of 69Br
Sp(69Br) = -785 (35) keV

30. Coulomb energy differences between mirror nuclei8 14
Sp(69Br) = -785 (35) keV ?
Anything new ?
d5/2 20
s1/2+d3/2 28
f7/2
p3/2
f5/2

31. Nuclear Physics：test IMME in 1f7/2 shell
N=Z
IAS
+ perturbation

32. Nuclear Physics：test IMME in 1f7/2 shell
M (53Ni; gs) ?
M (53Co; IAS) ?
IMME broken ?

33. 4. Summary & persperctives
78Kr, 58Ni fragmentation 13 10
65As: waiting point
Sp(69Br)=-785(35) ?
2. 53Ni: IMME ?
43V,47Mn: XRBs ?

34. Previous time Detectors
In progress
Previous time Detectors
IMS: double ToF
SMS method
Two Time Detectors
Schottky Pick-up

35. Exp. scheduled in Feb. 2012
Tz= -2 ( 58Ni Beam)

36. International collaborations:

37. Thank you for your attention and welcome you to visit IMP, Lanzhou