contentm(28si)= 27.976 926 532 6 u δm = 0.000 000 001 9 u rel. precision = 6x10-11 distance...
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www.quantum.physik.uni-mainz.de/mats/
ContentKlaus Blaum: University of Mainz and GSI Darmstadt
High-precision Penning trap experiments for fundamental studies
Motivation and history
Experimental setup and measurement procedure
Summary
High-precision g-factor measurements
High-precision mass measurements
Seattle, Fundamental Symmetries, 19.09.2007
www.quantum.physik.uni-mainz.de/mats/
Part I
High-precisionmass measurements
www.quantum.physik.uni-mainz.de/mats/
Requirements for mass spectrometry
B(Z,N) = [(Nmn + Zmp + Zme – m(Z,N)]·c2
= N ·
– binding energy
+ Z · + Z ·
High-accuracy mass measurements allow one to determine the atomic and nuclear binding energies reflecting all forces in the atom/nucleus.
K. B., Phys. Rep. 425, 1-78 (2006)
www.quantum.physik.uni-mainz.de/mats/
Requirements for mass spectrometryHigh-accuracy mass measurements allow one to determine the atomic and nuclear binding energies reflecting all forces in the atom/nucleus.
δm/m
General physics & chemistry ≤ 10-5
Nuclear structure physics- separation of isobars
≤ 10-6
Astrophysics- separation of isomers
≤ 10-6
Weak interaction studies ≤ 10-8
Metrology - fundamental constants ≤ 10-9
CPT tests ≤ 10-10
QED in highly-charged ions- separation of atomic states
≤ 10-11
K. B., Phys. Rep. 425, 1-78 (2006)
www.quantum.physik.uni-mainz.de/mats/
Precision: A brief history of mass spectrometry
1930 1940 1950 1960 1970 1980 1990 2000 201010-12
10-11
10-10
10-9
10-8
10-7
10-6
10-5
10-4
10-3
Mas
s U
ncer
tain
ty
δm/m
year
28Si
PTMS
Reaction Q
RF Spectrometers
MassSpectrographs
single ion
ion cloud
m(28Si)= 27.976 926 532 6 uδm = 0.000 000 001 9 uRel. Precision = 6x10-11
Distance Mainz-Seattle8000km ± 0.5mm
SMILETRAP, MIT-TRAP (now at FSU), Seattle-TRAP, Mainz-TRAP
38Ca (T1/2 = 440ms)
CPT, ISOLTRAP, JYFLTRAP, LEBIT, SHIPTRAP
www.quantum.physik.uni-mainz.de/mats/
Penning trap facilities worldwide
K.B., Phys. Rep. 425, 1 (2006)
www.quantum.physik.uni-mainz.de/mats/
Principle of Penning trap mass spectrometry
Cyclotron frequency:
Bmqfc ⋅⋅=
π21
B
q/m
PENNING trapStrong homogeneous magnetic fieldWeak electric 3Dquadrupole field
z0
r0
ring electrode
end capTypical frequenciesq = e, m = 100 u,B = 6 T⇒ f- ≈ 1 kHz
f+ ≈ 1 MHz
Brown & Gabrielse, Rev. Mod. Phys. 58, 233 (1986)
www.quantum.physik.uni-mainz.de/mats/
Time-of-flight ion cyclotron resonance detection
MCPDetector
(1) Excitation of theion motion
(3) TOF measurement
(2) Energy conversion
e
e
mmmm
ff
--
=refc
refc,Determine atomic mass from frequency ratio
with a well-known “reference mass”.
Bmq
πf 21
=c
Centroid:
0 1 2 3 4 5 6 7 8 9240
270
300
330
360
390
63Ga T1/2 = 32.4 sMea
n tim
e of
flig
ht /
μs
Excitation frequency νRF - 1445125 / Hzfrf
www.quantum.physik.uni-mainz.de/mats/
ISOLDEbeam (DC)
HV platform
RFQ structure
MCP 5
precisionPenningtrap
coolingPenningtrap
carbon clusterion source
2.8-keV ionbunches
laser beam
MCP 3
MCP 1
60 keV
stable alkaliion referencesource
C60 pellet
80
100
120
140
160
180
200
220 32ArM
ean
TOF
(μs)
νRF − 2842679 (Hz)-40 -30 -20 -10 0 10 20 30
F. Herfurth, et al., NIM A 469, 264 (2001)K. Blaum et al., NIM B 204, 478 (2003)
cluster ion source
preparation Penning trap
precision Penning trap
stable alkali ionreference source
ion beam cooler and buncher
removal of contaminant ions
(R = 105)
determination of cyclotron frequency
(R = 107)
B = 4.7 T
B = 5.9 T
Nd:YAG 532 nm
1.2
m
10 cm10 cm
Triple-trap mass spectrometer ISOLTRAP
8 m
8 m
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Resolution and isolation of nuclear isomers
1+
6-
1+
240
270
300
330
360
390
240
270
300
330
360
390
260
280
300
320
340
360
380
400
mea
n TO
F (u
s)
fexc - 1338940 (Hz)0 5 10 15 20 25 30 35
6-
Isomerism in 68Cu: as producedby ISOLDE
isolation of the 1+ ground state
isolation of the 6- isomeric state
Preparation of an isomerically pure beamClear state-to-mass assignmentsTrap-assisted decay and laser spectroscopy
0+
1+
721.6 keV6-
g: T1/2 = 31.1 sm:T1/2 = 3.75 min
IT 84%
16%
100%68Cu
68Zn
K. Blaum et al., Europhys. Lett. 67, 586 (2004)
Applications
www.quantum.physik.uni-mainz.de/mats/
Applications: Nucleosynthesis studiesK. Blaum et al., Phys. J. 5, 35 (2006); H. Schatz et al., Europhys. News 37, 16 (2006)
M. Mukherjee et al., Phys. Rev. Lett. 93, 150801 (2004) D. Rodríguez et al., Phys. Rev. Lett. 93, 161104 (2004)
Questions addressed:
• Why is iron so muchabundant than heavierelements such as gold?
• Why are there heavy elements at all and how did they come into existence?
• How can we explain theisotopic composition in the Universe?
www.quantum.physik.uni-mainz.de/mats/
Determination of Determination of thethe 7676Ge Ge ββ--DecayDecay QQ--ValueValue
?)2(27634
7632 eveSeGe ++→ −
Question: Is there a ν-less double β-decay?
Reaction:
Mass determination of 76Ge and 76Se
0 22 23-30
-20
-10
0
10
20
76Ge
Mea
sure
d de
viat
ion
[ppb
]
Ion charge state
0 22 23
-30
-20
-10
0
10
20
0 24 25-30
-20
-10
0
10
20
76SeM
easu
red
devi
atio
n [p
pb]
Ion charge state
0 24 25
-30
-20
-10
0
10
20
Q-value of 76Ge (0vββ) :
1 2 32038.0
2038.5
2039.0
2039.5
2040.0
2040.5
2041.0
2041.5
Q-v
alue
Measurement number
7-fold improvement of the Q-value (δm/m = 1 10-9)G. Douysset et al., Phys. Rev. Lett. 86 (2001) 4259.H.V. Klapdor-Kleingrothhaus et al., Mod. Phys. Lett. A 16 (2001) 2409.Performed at SMILETRAP (Stockholm)
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Isobaric Multiplet Mass Equation
Tz -3/2 -1/2 1/2 3/2
Me
T=1/2T=1/2
T=3/2 T=3/2T=3/2
T=3/2
33Ar 33Cl 33S 33P
M = a + bTz + cTz2
Commonly usedquadratic form ?
+ dTz3
A = 33, T = 3/2 quartet:
Mass formula for multiplets of nuclear states with same mass and isospin
www.quantum.physik.uni-mainz.de/mats/
Most stringent test of IMME (with 32,33Ar)
0 10 20 30 40 50 60-60
-40
-20
0
20
40
60
A
1
-10
Ground state quartets Excited state quartets Ground state quintets
d/
keV
A = 33, T = 3/2 quartet:A = 32, T = 2 quintet:
d = -0.13(45) keVd = -0.11(30) keV
ISOLTRAP measurements 2003:– 33Ar with u (m ) = 0.44 keV– 32Ar with u (m ) = 1.8 keV
New status:K. B. et al., Phys. Rev. Lett. 91, 260801 (2003).
www.quantum.physik.uni-mainz.de/mats/
Recent results of fundamental studies
Population inversion of nuclear states andnuclear structure studies:
J. Van Roosbroeck et al., Phys. Rev. Lett. 92, 1112501 (2004)K. Blaum et al., Europhys. Lett. 67, 586 (2004)Sz. Nagy et al., Phys. Rev. Lett. 96, 163004 (2006)C. Rauth et al., Phys. Rev. Lett., submitted (2007)
Why are there elements heavier than iron?D. Rodríguez et al., Phys. Rev. Lett. 93, 161104 (2004)M. Mukherjee et al., Phys. Rev. Lett. 93, 150801 (2004)
Are there scalar currents present in the Weak Interaction?F. Herfurth et al., Phys. Rev. Lett. 87, 142501 (2001) K. Blaum et al., Phys. Rev. Lett. 91, 260801 (2003)
Vud – is unitarity violated in quark mixing?F. Herfurth et al., Eur. Phys. J. A 15, 17 (2002)A. Kellerbauer et al., Phys. Rev. Lett. 93, 072502 (2004)M. Mukherjee et al., Phys. Rev. Lett. 93, 150801 (2004)S. George et al. Phys. Rev. Lett. 98, 162501 (2007)
See talk by J. Hardy and I. Towner tomorrow
d's'b'
dsb
Vud
Vcd
Vtd
Vus Vub
VcbVcs
VtbVts
= ·
1+
6-
260
280
300
320
340
360
380
400
νexc – 1338940 (Hz)
Mea
ntim
e of
flig
ht(μ
s)
1+
6-
260
280
300
320
340
360
380
400
νexc – 1338940 (Hz)
Mea
ntim
e of
flig
ht(μ
s)
www.quantum.physik.uni-mainz.de/mats
Future perspectivesWe want to perform mass measurements on rarely produced heavynuclides. (~1 particle per minute)
Need for
Nucleus Win, NUBASE Data
Cf
Bk
Cm
Am
Pu
Np
U
a non-destructive detection technique
single-particle sensitivity
a low-noise and cold environment
www.quantum.physik.uni-mainz.de/mats/
Non-destructive ion detection
x
y
Pickup-Electrode
Pickup-Electrode
ion current signal
Current
time
C. Weber, PhD thesis, University of Heidelberg (2004) and C. Weber et al., Eur. Phys. J A 25, 65 (2005)
Applications
– Mass measurements on heavy/superheavy rare elements– Fast identification and effective use of stored ions
Operation of traps and electronics at cryogenic (4 K) temperature.
„FT-ICR“ Fourier-Transform-Ion Cyclotron Resonance
f p
mass/frequency spectrum
Amplitude
frequency
very smallsignal ~fA
Amplification
Transformation
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Status FT-ICR mass spectrometry• traps assembled• 4K reached
• electronic testet• ion traping in progress
R. Ferrer and J. Ketelaer, PhD Thesis, University of Mainz, in preparation (2007)
Precision Penning trap
Cryogenic electronics
9 cm
Single ion sensitivity (singly charged heavy ion)!
www.quantum.physik.uni-mainz.de/mats
SpectroscopySpectroscopy setupsetup at at thethe Mainz TRIGA Mainz TRIGA reactorreactor
ion source
dipole massseparator
collinear laser beam line
Penning trap
laser table
TRIGAreactor
ion source
dipole massseparator
collinear laser beam line
Penning trap
laser table
TRIGAreactor
mass spectrometryandcollinear laser spectroscopyon transuranium elements(Np-Cf) and neutron-rich nuclides
B
In Collaboration with:Klaus Eberhardt Gabriele HampelNorbert Trautmann
Laser spectroscopyteam:Christopher GeppertJörg KrämerWilfried Nörtershäuser
and GSI Darmstadt
www.quantum.physik.uni-mainz.de/mats/
Laser and Laser and massmass spectroscopyspectroscopy at FAIRat FAIR
2007 2008 2009 2010 2011 2012 2013 2014 2015
MATS
LaSpec
RFQ
dipole
ions
atoms
gas catcher
ions from Super-FRS
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Part II
High-precisiong-factor measurements
www.quantum.physik.uni-mainz.de/mats/
The g – factor
relation between magnetic dipole moment and angular
momentum
free lepton: gs = g-factor of the spin
www.quantum.physik.uni-mainz.de/mats/
Measurement principle for a proton
precisiontrap
analysistrapelectric potential
magnetic field lines
precisiontrap
analysistrapelectric potential
magnetic field lines
precisiontrap
analysistrapelectric potential
magnetic field lines
Eigenmotions of the particle cyclotron frequency
Bme
pc =ω
We aim for δg/g < 10-9.
Zeeman splitting in the spin eigenstates Larmor frequency
BmegB
ppL 2
2=
⋅=
h
μω
Lωh
c
Lpg
ωω
⋅= 2
www.quantum.physik.uni-mainz.de/mats/
magnetic moment (g - 2)
(g - 2)
q/m
charge/mass
mass difference
10-610-910-1210-1510-18
1s–2s two-photon spectroscopy
rel. precision
e+ e-
μ+ μ-
e+ e-
H H
K0 K0
p p
Test of CPT invariance– Currently believed to hold– CPT transforms particle into its
antiparticle (P. Dirac 1928)
ωc: cyclotron frequencyωL: Larmor frequency
c
Lpg
ωω
⋅= 2
PDG: gp = 2×2.792847337(29) gp = 2×2.800(8)
With our double Penning-trap technique we aim for δg/g = 10-9.
1s-2s two-photon spectroscopy
gg--factorfactor of of thethe protonproton and and thethe antiprotonantiproton
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Hybrid analysis trap
1 cm ± 1 μmManufactured at the
Institute for MicrotechniqueMainz (IMM).
J. Verdú et al., AIP Conference Proceedings 796, 260-265 (2005)
Status of the (anti)proton g-factor experiment
www.quantum.physik.uni-mainz.de/mats/
- Unitarity test of the CKM matrix:δm/m<10-8 for short-lived radionuclides
- Test of E=mc2: δm/m<10-10 for 32S, 33S
- Test of CPT invariance: δg/g<10-9 for proton and antiproton
- Test of bound-state QEDδg/g<10-9 for hydrogen-like highly-charged ions
- Determination of fundamental constants:me, mp, α, Nah, μ, …
Penning traps are ideal tools to perform high-precision experiments for fundamental studies!
Summary
Email: blaumk@uni-mainz.de www.quantum.physik.uni-mainz.de/en/mats
Thanks a lot for your attention.
www.quantum.physik.uni-mainz.de/mats/
The Helmholtz-Research-Group MATS
In collaboration with: H.-J. Kluge, H. Kracke, M. Kretzschmar, W. Quint, L. Schweikhard, S. Stahl, J. Walz, G. Werth
and the ISOLTRAP team
„Mass“-Team
„g-Factor“-Team
M. Dworschak (PhD), G. Eitel (Dipl.), R. Ferrer (PhD), S. George (PhD), J. Ketelaer (PhD), S. Nagy (PostDoc), D. Neidherr (PhD), J. Repp (Dipl.), Ch. Smorra (Dipl.) S. Kreim (PhD), C. Rodegheri (PhD), S. Sturm (PhD), B. Schabinger (PhD), S. Ulmer (PhD), A. Wagner (Dipl.)
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