Masses of tripline nuclei Frank Herfurth, ISOLDE/CERN.
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Transcript of Masses of tripline nuclei Frank Herfurth, ISOLDE/CERN.
Masses of tripline nuclei
Frank Herfurth, ISOLDE/CERN
Mass measurements
ReactionA(a,b)B
Q = MA + Ma – MB – Mb
Alpha-decayA B + Q = MA– MB – M
Time of flight TOFI (LANL) SPEG/CSS2 (Ganil) SARA (ISN) ESR (GSI)
Cyclotron frequency Penning traps MISTRAL (ISOLDE)
Schottky noise analysis ESR (GSI)
INDIRECTINDIRECT DIRECT (mass spectrometry)DIRECT (mass spectrometry)
ISOLTRAP
G. Bollen et al., NIM A 368 (1996) 675H. Raimbault-Hartmann, NIM B 126 (1997) 378
F. Herfurth et al., NIM A 469 (2001) 254
accumulation & bunching of
ISOLDE 60 keV beam
coolingisobar separation
Rm
m
1 105
determination of cyclotron frequency
Rm
m
5 106
1m
Bunches,3keV energy
60keV ISOLDE-
ion beam
1 cm
5 cm
60 000 V
B = 4.7 T
B = 6 T
Linear RFQ trap
Past
Required Yield Half-life Relative mass accuracy yT1/2 m/m
103
104
105
101
102
100ms
1s
10s
1ms
10ms
10-8
10-7
10-6
10-10
10-9
Future
32Ar 74Rb 34Ar
Present
ISOLTRAP performance
ISOLTRAP measurements
74Rb
32, 34Ar
76Sr
132Sn
1995 ... 1999
72Kr
74Rb
72Kr
76Sr
132Sn
216Bi
32, 34Ar
2000 .. 2002
Highlights:
ISOLTRAP measurements
150Ho and the dripline
NEUTRONS
PR
OT
ON
S
150Ho
150Ho is an anchor point for long decay chains
Influence of ISOLTRAP data
-1500
-1000
-500
0
500
1000
1500
2000
2500
81 83 85 87 89 91 93 95
NEUTRON NUMBER N
Sp
[keV
]
Liran +Zeldes
Ho
Tm
Lu Ta ReIr Au Tl
150Ho
149Ho
151TmAME95 excl. TRAP(-chain to150Ho)
AME95 incl. TRAP
Argonne
Dripline changed by the ISOLTRAP measurement of 150Ho
rp-process above Z = 32N=Z
Ge70 Ge72 Ge73 Ge74
Se74
As75
Ge76
Se76 Se77 Se78
Kr78
Br79
Se80
Kr80
Br81
Kr82
Sr84
P
P
P
Ge62 Ge63
As63
Ge64
As64
Ge65
As65
Se65
Ge66
As66
Se66
Ge67
As67
Se67
Br67
Ge68
As68
Se68
Br68
Ge69
As69
Se69
Br69
Kr69
As70
Se70
Br70
Kr70
Ge71
As71
Se71
Br71
Kr71
Rb71
As72
Se72
Br72
Kr72
Rb72
As73
Se73
Br73
Kr73
Rb73
Sr73
As74
Br74
Kr74
Rb74
Sr74
Ge75
Se75
Br75
Kr75
Rb75
Sr75
As76
Br76
Kr76
Rb76
Sr76
Ge77
As77
Br77
Kr77
Rb77
Sr77
Y77
Ge78
As78
Br78
Rb78
Sr78
Y78
As79
Se79
Kr79
Rb79
Sr79
Y79
Br80
Rb80
Sr80
Y80
Kr81
Rb81
Sr81
Y81
Rb82
Sr82
Y82
Rb83
Sr83
Y83 Y84 Y85
34
35
36
37
38
Z = 39
(H. Schatz et al. Phys. Rep. 294 (1998) 167)
possible waiting points
possible rp - process main path
mass excess not yet measured (AME95)
Mass model – experiment comparison
H. Schatz et al. Phys. Rep. 294 (1998) 167
mass number A
possible waiting point
Sr and Kr results
0
ISOLTRAP
AME95
CSS2 (GANIL)A.S. Lalleman et al., Hyp. Int. 132 (2001) 315
0
ISOLTRAP
AME95
possible waiting point
- correlation – 32Ar decay
E.G. Adelberger et al., Phys. Rev. Lett. 83 (1999) 1299
0
2
4
6
8
10
MeV
31S32Cl
32Ar
IAS
+
p
0+,2
0+,2
1/2+
32Ar 32Cl* 31S
e+
R
Precursor
p
Intrinsic shape of the proton-group
a = +1
a = -1
32Ar – search for scalar currents
present limit:a = 0.9989 ± 0.0052(stat) ± 0.0039(sys)
but Q from IMME and:a/Q = -1.2·10-3 keV-1
0
2
4
6
8
10
MeV
31S32Cl
32Ar
IAS
+
p
0+,2
0+,2
1/2+
32Ar 32Cl* 31S
e+
R
Precursor
p
-40 -30 -20 -10 0 10 20 3080
100
120
140
160
180
200
220
32Ar
Me
an
TO
F ( s
)
RF
- 2842679 (Hz)
m/m ~ 1·10-7, i.e. m ~ 3 keV
371 ions, Tobs = 100ms
ISOLTRAPISOLTRAP
Summary
Direct and indirect techniques are needed to access dripline nuclei
ISOLTRAP provides both very precise measurements to anchor long
decay chains direct access to nuclei very close to the
dripline
The ISOLTRAP collaboration
Dietrich Beck
Klaus Blaum
Jürgen Kluge
Daniel Rodríguez
Christoph Scheidenberger
Günther Sikler
Christine Weber
NSCL/MSU EastLansing
Georg Bollen
Stefan Schwarz
GSI Darmstadt CERN Geneva
Alban Kellerbauer
Markku Oinonen
Frank Herfurth
Emanuel Sauvan
LMU Munich
Friedhelm Ames
Michael Kuckein
Sylvain Henry
Jurek Szerypo
McGill Univ. Montreal
Robert B. Moore
CSNSM Orsay
Georges Audi
David Lunney
Univ. of Jyväskylä
Veli Kolhinen
and the ISOLDE collaboration