October 7, 2008
SPIN 2008
Univ. of Virginia
Review of Electric Dipole Moment
experiments
Special preview: muon g-2 and mu2e
Yannis K. Semertzidis, BNL
From Table-Top to Storage-Ring Experiments
1) Techniques and status of some major EDM
experiments
2) New developments, future of the field
EDM methods
• Neutrons: Ultra Cold Neutrons, apply large
E-field and a small B-field. Probe frequency
shift with E-field flip
• Atomic & Molecular Systems: Probe 1st
order Stark effect
• Storage Ring EDM for charged particles:
Utilize large E-field in rest frame-Spin
precesses out of plane (Probe angular
distribution changes)
Important Stages in an EDM
Experiment
1. Polarize: state preparation, intensity of beams
2. Interact with an E-field: the higher the better
3. Analyze: high efficiency analyzer
4. Scientific Interpretation of Result! Easier for
the simpler systems
Yannis Semertzidis, BNL
EDM method Advances
• Neutrons: advances in stray B-field effect
reduction; higher UCN intensities
• Atomic & Molecular Systems: high effective
E-field
• Storage Ring EDM for D, P: High intensity
polarized sources well developed; High electric
fields made available; spin precession
techniques in SR well understood
EDM method Weaknesses
• Neutrons: Intensity; High sensitive to stray
B-fields; Motional B-fields and geometrical
phases
• Atomic & Molecular Systems: Low intensity of
desired states; in some systems: physics
interpretation
• Storage Ring EDM: sensitive to vertical
E-fields; some systematic errors different from
g-2…
Spin is the only vector defining
a direction…
̂
+
-

d 0

d  d̂
A Permanent EDM Violates
both T & P Symmetries:
+
T
-
+
P
+
EDM physics without spins is not important
(batteries are allowed)
A charged particle in an Electric
Field…
-
+
E
-
How about an electron in an atom…
Schiff Theorem:
A Charged Particle at
Equilibrium Feels no Force…
…An Electron in a Neutral
Atom Feels no Force Either:
FTotal  q ETotal  q Eext  Eint  0
…Otherwise it Would be Accelerated…(Note: Schiff actually said the opposite…)
Yannis Semertzidis, BNL
Neutron EDM Vs Year
Neutron EDM Limits
1000000
Purcell and Ramsey started…
10^-25 e-cm
100000
10000
1000
100
10
1
0.1
50
60
70
Year
80
90
“…at 6 x 10-26 e cm, it is analogous to the Earth's surface being smooth
and symmetric to less than 1 µm” (John Ellis).
EDM in an Electric Field…
d
ds
 d E
dt
+
-
+
E
-
Precession of a Top in a
Gravitational Field


mgl
 
, L  IS
L
nEDM Experimental Method





ds
 Bd E
dt
Carrier Signal
E
Small Signal
Compare the Zeeman Frequencies
When E-field is Flipped:
1  2   4dE
1
d 
E
1
NT
Measuring an EDM of Neutral Particles
H = -(d E + μ B) ● I/I
B
E
d
ω1
ω1=
2 B  2dE
B
µ
E
d
ω2
ω2 =
mI = 1/2
ω1
µ
2 B  2dE
(ω -ω )
1
2
d=
4E
ω2
mI = -1/2
d = 10-25 e cm
E = 100 kV/cm

 = 10-4 rad/s
Ramsey’s method
Yannis Semertzidis, BNL
neutron EDM exps in preparation
• PSI: Ramsey’s method of separated oscillatory
fields. First goal 110-27ecm, begin data taking
~2009.
• UCN at ILL (Sussex, RAL,…): Ramsey’s
method of separated oscillatory fields. Goal
210-28ecm/year, begin data taking 2009.
• Ultra-Cold Neutrons (UCN), at SNS (LANL,…):
Polarized 3He stored together in a superfluid
4He. Goal 210-28 ecm, begin data taking
~2011.
Yannis Semertzidis, BNL
Neutron EDM:
Room-temperature experiment
Magnetic shielding
High voltage lead
Magnetic
field coil
Storage cell
E
B
Result:
|dn| < 2.9 x 10-26 e.cm (90% CL)
PRL 97, 131801 (2006); hep-ex/0602020
S
Magnet &
polarizing foil
/analysing
foil
UCN detector
N
Approx scale 1 m
Ultracold
neutrons
(UCN)
nEDM experiment
at ILL (Grenoble)
From P. Harris
UCN production in liquid helium
Dispersion curve for
free neutrons
R. Golub and J.M. Pendlebury
Phys. Lett. 53A (1975),
Phys. Lett. 62A (1977)
•
Landau-Feynman
dispersion curve for
4He excitations
ln = 8.9 Å; E = 1.03 meV
Parameter
•
•
•
•
•
1.03 meV (11 K) neutrons
downscatter by emission of phonon in
liquid helium at 0.5 K
Upscattering suppressed: Boltzmann
factor e-E/kT means not many 11 K
phonons present
Room-tmpr. expt
Polarisation+detection:
Electric field:
Precession period:
Neutrons counted:
(with new beamline)
 = 0.75
E = 106 V/m
T = 130 s
N = 6 x 106 /day
Total increase approx factor 100
Sensitivity
x 1.2
x4
x2
x 4.5
x 2.6
CryoEDM overview
Neutron beam input
Cryogenic
Ramsey chamber
• Construction nearly complete
• First neutron storage in Ramsey
measurement cells expected end 2008
• Website: www.neutronedm.org
Transfer section
HV feed
Approx scale 3 m
UCN Source at PSI
Latest news:
UCN tank delivered at PSI on September 4th, 2008
2m3 vacuum
UCN storage
30 liters, 5K
solid D2
p-beam
1.2 MW
1% duty cycle
• Complete source construction in 2009
• Deliver several 109 UCN every ~400-800 s
• ~1000 cm-3 UCN in typical experiments
(today this is ~10 cm-3 at ILL Grenoble)
3m2 D2O
ucn.web.psi.ch
From Klaus Kirch, PSI
Neutron EDM Search
P, T
CP
Strategy: Experiment with UCN in
vacuum and apparatus at
ambient temperature. Use double
UCN chamber, co-magnetometry
• New collaboration (12 groups, 45
and multiple external
people) operates and improves this
magnetometers.
apparatus at ILL Grenoble (Phase I)
nedm.web.psi.ch
• Move to PSI beginning of 2009
• Operation at PSI 2009 – 2011 (Phase II)
Sensitivity goal: 5x10-27ecm
• New experiment operational 2011
• Operation 2011 – 2015 (Phase III)
Sensitivity goal: 5x10-28ecm
The Neutron EDM Collaboration
M. Burghoff, S. Knappe-Grüneberg,
T. Sander-Thoemmes, A. Schnabel, L. Trahms
Physikalisch Technische Bundesanstalt, Berlin
G. Ban, Th. Lefort, O. Naviliat-Cuncic, E. Pierre1
Laboratoire de Physique Corpusculaire, Caen
K. Bodek, St. Kistryn, M. Kuzniak1, J. Zejma
Institute of Physics, Jagiellonian University, Cracow
N. Khomutov
Joint Institute of Nuclear Reasearch, Dubna
P. Knowles, A.S. Pazgalev1,2, A. Weis
Département de physique, Université de Fribourg, Fribourg
N.N., G. Rogel3
Institut Laue-Langevin, Grenoble
G. Quéméner, D. Rebreyend,
S. Roccia, M. Tur
Laboratoire de Physique Subatomique et de Cosmologie, Grenoble
G. Bison
Biomagnetisches Zentrum, Jena
N. Severijns
Katholieke Universiteit, Leuven
K. Eberhardt, G. Hampel, W. Heil, J.V. Kratz,
T. Lauer, C. Plonka-Spehr, Yu. Sobolev4, N. Wiehl
Johannes-Gutenberg-Universität, Mainz
I. Altarev, P. Fierlinger, E. Gutsmiedl, M. Horras1,
S. Paul, R. Stoepler
Technische Universität, München
M. Daum, R. Henneck, K. Kirch, A. Knecht5, B. Lauss,
A. Mtchedlishvili, G. Petzoldt, G. Zsigmond
Paul Scherrer Institut, Villigen
also at: 1Paul Scherrer Institut, 2Ioffe, 3LPC Caen, 4PNPI Gatchina, 5University of Zürich
The nEDM Project
Martin Cooper
Co-spokesperson, CPM
Los Alamos National
Laboratory
nEDM at Spallation Neutron Source
By Martin Cooper
3
Deuteron EDM, UoR,
18 April, 2006
Yannis Semertzidis, BNL
Applying spin dressing techniques to equalize and further reduce
the stray B-field sensitivity
nEDM Collaboration
R. Alarcon, S. Balascuta, L. Baron-Palos
Arizona State University, Tempe, AZ, USA
D. Budker, A. Park
University of California at Berkeley, Berkeley, CA 94720,
USA
G. Seidel
Brown University, Providence, RI 02912, USA
A. Kokarkar, V. Logashenko, J. Miller, L. Roberts
Boston University, Boston, MA 02215, USA
J. Boissevain, R. Carr, B. Filippone, R. McKeown,
M. Mendenhall, R. Schmid
California Institute of Technology, Pasadena, CA 91125,
USA
M. Ahmed, W. Chen, H. Gao, X. Qian, Q. Ye,
W.Z. Zheng, X. F. Zhu, X. Zong
Duke University, Durham NC 27708, USA
F. Mezei
Hahn-Meitner Institut, D-14109 Berlin, Germany
C.-Y. Liu, J. Long, H.-O. Meyer, M. Snow
Indiana University, Bloomington, IN 47405, USA
L. Bartoszek, D. Beck, P.. Chu, A. Esler, J.-C. Peng,
S. Williamson, J. Yoder
University of Illinois, Urbana-Champaign, IL 61801, USA
C. Crawford, T. Gorringe,
W. Korsch, B. Plaster
University of Kentucky, Lexington KY 40506, USA
B. Bourque, S. Clayton, M. Cooper, M. Espy, R.
Hennings-Yeoman, T. Ito, A. Matlachov, C. Mauger, E.
Olivas, J. Ramsey, I. Savukov, W. Sondheim, S.
Stanislaus, S. Tajima, J. Torgerson, P. Volegov
Los Alamos National Laboratory, Los Alamos, NM 87545,
USA
E. Beise, H. Breuer
University of Maryland, College Park, MD 20742, USA
K. Dow, D. Hassel, E. Ihloff, J. Kelsey, R. Milner,
R. Redwine, C. Vidal
Massachusetts Institute of Technology, Cambridge, MA
02139, USA
J. Dunne, D. Dutta
Mississippi State University, Starkville, MS 39762, USA
F. Dubose, R. Golub, C. Gould, D. Haase, P. Huffman,
E. Korobkina, C. Swank, A. Young
North Carolina State University, Raleigh, NC 27695, USA
V. Cianciolo, S. Penttila
Oak Ridge National Laboratory, Oak Ridge, TN 37831,
USA
M. Hayden
Simon-Fraser University, Burnaby, BC, Canada V5A 1S6
G. Greene
The University of Tennessee, Knoxville, TN 37996, USA
S. Lamoreaux, D. McKinsey, A. Sushkov
Yale University, New Haven, CT 06520, USA
The Permanent EDM of the
Neutron
• A permanent EDM d
d•E
+
s = 1/2
• The current value is < 3 x 10-26 e•cm (90% C.L.)
-28
• Hope to obtain roughly < 2 x 10 e•cm with
UCN in superfluid He
Sensitivity
The Basic Equation
Light response from scintillations of
polarized 3He(n,p)t reaction products


1

1
 p t
 (t )   B (t )  Ne
  1  Pn P3 e cos( 2 f  t   ) 
   3

1
1
1
ave 
 
 avet

3
 cell
Determine f and df
Change in f with E measures the EDM
df determines the sensitivity
EDM Experiment - Vertical
Section View
ABS
DR
Upper Cryostat
Services
DR LHe Volume
~450 liters
3He Injection
Volume
3He Injection
Volume
Cosq magnet
4-layer
-metal shield
ABS Line
Central LHe Volume
~400 mK, ~1000 liters
Reentrant
Neutron
Guide
Upper
Cryostat
~6 m
Lower
Cryostat
Coil and Shield Nesting
Inner-Dressing &
Spin-Flip Coil
50K Shield
Outer Dressing Coil
4K Shield
Superconducting
Lead Shield
Ferromagnetic
Shield
B0 cosθ Magnet
Funding
• Total DOE funding = $11,795k
• Total NSF funding = $7,450
Schedule
• Feb 2007 Conceptual Design Approved
• Feb 2009 Technical Feasibility, Preliminary
Engineering, Cost and Schedule Baseline Approved
• Aug 2009 Construction Approved
• Jan 2010 Beneficial Occupancy of FnPB UCN
Building
• Oct 2015 nEDM Project Completed
• 2018
First Published Results @ few ´ 10-27 e•cm
• 2020
nEDM Experiment Completed and Published
@ few ´ 10-28 e•cm
Neutron EDM Timeline
2005
Exp begin
data taking
Exp goal
2007
2008
UCN-PSI
~10-27ecm
2009
UCN-ILL
210-28ecm/yr
2011
UCN-LANL/SNS
<210-28ecm
Yannis Semertzidis, BNL
Schiff Theorem:
A Charged Particle at Equilibrium Feels no Force…
…An electron in a neutral atom feels no force either. However, the
average interaction energy is not zero because the EDM in the lab
frame is velocity dependent
E. Commins et al., Am. J. Phys. 75 (6) 2007
Current Atomic EDM Limits
• Paramagnetic Atoms, 205Tl: electron
|de| < 1.610-27e·cm (90%CL)
PRL 88, 071805 (2002)
• Diamagnetic Atoms, 199Hg Nucleus:
|d(199Hg)| < 2.110-28e·cm (95%CL)
PRL 86, 2505 (2001)
Yannis Semertzidis, BNL
Deuteron EDM, UoR,
18 April, 2006
Yannis Semertzidis, BNL
A difference in the energy of a paramagnetic atom/molecule spinning
clockwise or counterclockwise about a pure electric field is
proportional to an e-EDM.

 
U   B ( gB  g EDM E )  F
backgound
measurement
The current e-EDM limit of ~10-27 e cm is from the measured
energy difference between
MF=±1 states of Tl atoms in a magnetic field
that is alternatively parallel and anti-parallel to an electric field.
(Commins & Coworkers, PRA 88, 2002)
From Neil Shafer Ray
An untapped resource: Heavy paramagnetic molecules are
approximately10,000 times more sensitive to an e-EDM than atoms.
Can we reach 10-31 e cm??
Active drill sites:
PbF: University of Oklahoma
(Shafer-Ray)
ThO: Yale, Harvard, (DeMille,
Doyle, Gabrielse)
HfF+: NIST, NRC, University of
Colorado (Eric Cornell,
John Bohn)
YbF: Oxford (Ed Hinds)
PbO: Yale (David DeMille)
WC: Michigan (Aaron Learnhardt)
Deformed nuclei
•
225Ra
•
225Ra
at Argonne National Lab, Roy Holt et al.
(starting tests with Ba) at KVI (The
Netherlands): K. Jungmann, L. Willmann…
Enhanced EDM of Radium-225
Enhancement mechanisms:
• Large intrinsic Schiff moment due to octupole deformation;
• Closely spaced parity doublet;
• Relativistic atomic structure.
Parity doublet
|+
|-
Haxton & Henley (1983)
Auerbach, Flambaum & Spevak (1996)
Engel, Friar & Hayes (2000)
Enhancement Factor: EDM (225Ra) / EDM (199Hg)
Skyrme Model
  |  |/2
55 keV
  |  |/2
Isoscalar Isovector
Isotensor
SkM*
1500
900
1500
SkO’
450
240
600
Schiff moment of 199Hg, de Jesus & Engel, PRC (2005)
Schiff moment of 225Ra, Dobaczewski & Engel, PRL (2005)
From Roy Holt
An Experiment to Search for EDM of
225Ra
Status and Outlook
• First atom trap of radium realized;
Oven:
225Ra (+Ba)
225Ra
Nuclear Spin = ½
Electronic Spin = 0
t1/2 = 15 days
Guest et al. PRL (2007)
• Search for EDM of 225Ra in 2009;
• Systematic improvements will follow.
Zeeman
Slower
Why trap 225Ra atoms
• Large enhancement:
EDM (Ra) / EDM (Hg) ~ 200 – 2,000
• Efficient use of the rare 225Ra atoms
• High electric field (> 100 kV/cm)
• Long coherence times (~ 100 s)
• Negligible “v x E” systematic effect
Magneto-optical
trap
EDM
probe
Optical
dipole trap
TRIP project and facility
Magnetic
Separator
Ion
Catcher
RFQ
Cooler
Atomic Physics
Production
Target
Nuclear Physics
AGOR
cyclotron
Wedge Q
MeV
D
Particle Physics
Q Q
Q
D
D
Q
Q
D
keV
Production
target
Q
Q
eV
meV
MOT
Beyond the
Standard Model
TeV Physics
Magnetic separator
thermal ioniser
RFQ cooler/buncher
neV
AGOR cyclotron
MOT
MOT
Low energy beam line
Trapped Radioactive Isotopes: icro-laboratories for Fundamental Physics
TRIP
Why Radium?
Atomic energy level diagram of Ra
7s7p 1P1

Nearly degenerate opposite parity
3P and 3D enhancement >
~5000
10 4 e EDM
1
1
2
2
7s6d 1D2
7s7p
3P
1
0
7s6d 3D
3
2
1
 3D12 | er | 3P1  3P1 | H EDM | 3D12 
d
E ( 3D12 )  E ( 3P1 )
V. A. Dzuba et al. Phys. Rev. A, 61, 062509 (2000)
482.7 nm
Density distribution of nuclear charge has
mixed octupole and quadrupole deformation
7s2 1S0
 Deformed charge distribution
in some isotopes (225Ra). Nucleon
EDM enhances ≈ 102
J. Engel et al. Phys. Rev. C, 68, 025501 (2003)
Periodic Table of Elements
TRIP
Barium MOT
λ1, λ2,, λ3
|R>
coil-II
PMT
I
l/4
|L>
l/4
|L>
Velocity
atomic
beam
lIR2,
lIR3
l1, lIR2, lIR3
lIR1
λ1, λ2, λ3
z
|L
>
coil-I
l/4
y
x
|L
>
I
|R>
λ1 , λ2 , λ3
Laser Setup
1500 nm (15 mW, δ= 0 MHz)
1130 nm (40 mW, δ= 0 MHz)
λir1
fiber laser
Pmt with filter
at λ1 or λB
Vertical MOT beam
not shown
Slowing beam
λ1
25 mW,
δ = -220 MHz
λir2
fiber laser
l/4
l/4
l/4
l/4
Ba Oven
~ 820K
90 mW
λir3
mag. field coils
fiber laser
λit3
diode laser
MOT beams
20 mW, Ø=12 mm
δ = -10 MHz
trapping
laser λ1
λ3
diode laser
10 mW
λir2
diode laser
1500 nm, 5 mW, δ = -80 MHz
1130 nm, 25 mW, δ = -105 MHz
TRIP
Big Step: Efficient Trapping of Barium Atoms
5d6p 3D1
l = 413.3 nm
l=
667.7 nm
- Scheme avoids dark resonances
- 7 lasers at one time needed
- 1.5 s trap lifetime sufficient
l=
6 atoms trapped
659.7 nm - 10
- improvements possible
- 104 higher trapping efficiency
achieved than for Ra
- at TRIP 105 213Ra atoms
expected in trap
150
150
150
140
140
140
● Doppler-free beam
signal (*100)
130
130
130
33
11
3D - 1S Fluorescence [Counts/s]
D111- S000 Fluorescence [Counts/s]
● MOT signal
MOT
repumpingonon
●●repumping
●
●repumping
repumpingoff
off
120
120
120
110
110
110
MOT
>
106 trapped
atoms
100
100
100
90
90
90
80
80
80
70
70
70
60
60
60
50
50
50
40
40
40
-500
-500
-500
S. 2007
De, L. Willmann, 3 Oct 2007
S. De, L. Willmann, 3 Oct
-250
250
-250
000
250
-250
250
Longitudinalvelocity
velocityofof
of
theatoms
atoms
[m/s]
Longitudinal
the
[m/s]
Longitudinal
velocity
the
atoms
[m/s]
500
500
TRIP
Radium – Barium Optical Trapping
very similar level schemes – very similar leak rates
 Cooled and trapped on intercombination line  Cooled and trapped on resonance line

with Zeeman slower
with many laser repumping
(Argonne: Phys. Rev. Lett. 98, 093001, 2007)
(KVI: S. De, L. Willmann et al., arXiv:0807.4100, 2007)
7∙10-7 cooling
& trapping efficiency
from atomic beam
 ~20 225Ra (7000 226Ra) atoms trapped
 10-2 cooling & trapping efficiency
from atomic beam
 106 xxBa atoms trapped
 method transferrable to Radium
The Storage Ring EDM experiment
The Storage Ring EDM
Store Longitudinally polarized beams
0.8m
Bend section (BE)
9m
8.4m
8.4m
0.864 m
Straight section
g-2 precession: in plane
EDM precession: out of plane
Deuteron EDM sensitivity: 10-29 ecm
Proton EDM sensitivity: 3.5x10-29 ecm
The three spin components at the polarimeter
location for different g-2 cancelation factors:
NO EDM
Sz
Sx
Sy
The three spin components at the polarimeter
location for different g-2 cancelation factors:
NO EDM
Sz
Sx
Sy
The three spin components at the polarimeter
location for different g-2 cancelation factors:
WITH EDM
Sz
Sx
Sy
The three spin components at the polarimeter
location for different g-2 cancelation factors:
WITH EDM
Sz
Sx
Storage ring EDM: The deuteron
case (proton is similar)
•
•
•
•
•
High intensity sources (~1011/fill)
High vector polarization (~80%)
High analyzing power for ~1 GeV/c (250MeV)
Long spin coherence time possible (>103s)
Large effective E*-field
Freezing Spin Precession
1. Magic momentum: Proton, sens.: 3.5x10-29 ecm
2. Combined E&B-fields: Deuteron, sens.: 10-29 ecm

  m 2 
e
a   aB   a       E 
  p 
m




• Making the dipole B-field = 0, the spin precession is
zero at (magic) momentum
m
p
, i.e. the larger the a the better!
a
• Proton magic momentum is 0.7GeV/c
• Deuteron: Momentum 1 GeV/c, B=0.5 T, E=120KV/cm
deuteron EDM search at BNL
EDM storage ring
A longitudinally polarized
deuteron beam is stored in the
EDM ring for ~103s.
The strong effective E*-field~V×B will precess the
deuteron spinYannis
outSemertzidis,
of planeBNL
if CAD
it possesses
a non-zero EDM
meeting, May 2008
Storage
Ring
EDM
Collaboration
A collaboration
with strong motivation.
www.bnl.gov/edm
There is a need for
new collaborators
Possible dEDM Timeline
11
07 08
09
10
12 13 14
15
16
17
 Spring 2008, Proposal to the BNL PAC
• 2008-2012 R&D phase; ring design
• Fall 2011, Finish systematic error studies:
a) spin/beam dynamics related systematic errors.
b) Polarimeter systematic errors studies with polarized
deuteron beams
c) Finalize E-field strength to use
d) Establish Spin Coherence Time
• Start of 2012, finish dEDM detailed ring design
• Fall 2012, start ring construction
• Fall 2014, dEDM engineering run starts
• Fall 2015, dEDM physics run starts
Yannis Semertzidis, BNL CAD
meeting, May 2008
Tests at COSY ring at Juelich/Germany
E. Stephenson, G. Onderwater, et al.
Goals: Construct prototype
dEDM polarimeter. Install
in COSY ring for
commissioning, calibration,
and testing for sensitivity to
EDM polarization signal and
systematic errors.
Current location
behind present EDDA
detector.
Reporting activities related to dEDM
•
Polarimeter tests at KVI and COSY: Monday, by
Marlene da Silva e Silva
•
Spin Coherence Time for dEDM experiment:
Tuesday, by Fanglei Lin
•
Storage Ring EDM Experiment: Tuesday, by Gerco
Onderwater
•
Electric field development for dEDM: Friday, by
Vasily Dzhordzhadze
Physics Motivation of dEDM
 Currently : q  1010, Sensitivity with dEDM
: q  1013
• Sensitivity to new contact interaction: 3000 TeV
• Sensitivity to SUSY-type new Physics:


1TeV
dEDM  1024 e  cm  sin d  

 MSUSY 
2
The Deuteron EDM at 10-29e∙cm has a reach of
~300 TeV or, if new physics exists at the LHC
scale, 10-5 rad CP-violating phase. Both are
much beyond the design sensitivity of LHC.
Yannis Semertzidis, BNL
Overview of EDM experiments
1) EDMs with spins: First rate physics
2) It will not be done at LHC. Its physics is
complementary and many times much better
than the LHC reach.
3) The next decade promises to be very exciting
4) The experiments are very challenging and lots
of fun
Yannis Semertzidis, BNL
Short Preview of
• Muon g-2
• Muon to electron conversion (mu2e)
experiment at FNAL
Muon g-2 … Why? How? Where?
David Hertzog (UIUC)
• Muon magnetic dipole moment experiments are more than
50 years old
– … like other “precision” measurements, the method and
precision have certainly evolved !
• Emphasis on difference of g from 2, a 1/800 effect.
– In each generation, significant advances were made
• QED through many orders ~5th order
• Hadronic VP to better than 1%
• Weak loops required, through 2nd order
• g-2 measured now to 0.54 ppm
• From BNL, a 3.4  difference exists from SM
– a(expt – thy) ≈ 300 ± 88 x 10-11
– Statistics limited
• The next-generation effort is about precision input to pin
down the parameters of the New Standard Model
– Where should it be located ?
hertzog@uiuc.edu
Ideal conditions at FNAL using 8 GeV p


Long beamline possible; more , less flash
High repetition rate of muon fills in ring
fills / 1.4 sec  60 Hz  14.5 x BNL
 > 20 times statistics in one year
 84
Target where pbar target sits
g-2
A New Charged Lepton Flavor
Violation Experiment:
Muon-Electron Conversion
at FNAL
from Jim Miller, Boston Univ.
R.M. Carey, K.R. Lynch, J.P. Miller*, B.L. Roberts
Collaboration
Boston University
W. Marciano,Y. Semertzidis, P. Yamin
Brookhaven National Laboratory
Yu.G. Kolomensky
University of California, Berkeley
C.M. Ankenbrandt , R.H. Bernstein*, D. Bogert, S.J. Brice, D.R. Broemmelsiek,D.F. DeJongh, S. Geer, R. Kutschke,
M.A. Martens, D.V. Neuffer, M. Popovic, E.J. Prebys, M. Syphers, R.E. Ray, H.B. White, K. Yonehara, C.Y. Yoshikawa
Fermi National Accelerator Laboratory
D. Dale, K.J. Keeter, E. Tatar
Idaho State University
W. Molzon
Experiment’s 1st
Stage is MECO
adapted to FNAL
University of California, Irvine
many MECO
collaborators with
vital knowledge
P.T. Debevec, G. Gollin,D.W. Hertzog, P. Kammel
University of Illinois, Urbana-Champaign
V. Lobashev
Institute for Nuclear Research, Moscow, Russia
D.M. Kawall, K.S. Kumar
University of Massachusetts, Amherst
R.J. Abrams, M.A.C. Cummings, R.P. Johnson, S.A. Kahn,S.A. Korenev, T.J. Roberts, R.C. Sah
Muons, Inc.
J.L. Popp
added since June 2008
City University of New York, York
M. Corcoran
Rice University
R.S. Holmes, P.A. Souder
Syracuse University
M.A. Bychkov, E.C. Dukes, E. Frlez, R.J. Hirosky, A.J. Norman, K.D. Paschke, D. Pocanic
University of Virginia
What is μe Conversion?
muon converts to electron in the presence of a nucleus
• Charged Lepton Flavor Violation
•
(CLFV)
Related Processes:
–μ or τ → eγ, e+e-e, KL→μe, and more
69
Endorsed in US Roadmap
FNAL has proposed muon-electron conversion as a flagship
program for the next decade
Strongly endorsed by P5:
“The
experiment could go forward in the next decade with a modest evolution of
the Fermilab accelerator complex. Such an experiment could be the first step in a
world-leading muon-decay program eventually driven by a next-generation highintensity proton source. The panel recommends pursuing the muon-toelectron conversion experiment... under all budget scenarios considered by
the panel”
Mu2e is a central part of the future US program
Contributions to μe Conversion
also see Flavour physics of leptons and dipole moments, arXiv:0801.1826
Overview Of Processes
μ- stops in thin Al foil
μ- in 1s state
the Bohr radius is ~ 20 fm,
so the μ- sees the nucleus
nucleus
muon capture,
muon “falls into”
nucleus:
normalization

muon decay in orbit
nuclear muon capture
Al Nucleus
~4 fm
60% capture
40% decay
Decay in Orbit:
background
Detector and Solenoid
• Tracking and Calorimeter
•
Decay into muons and
transport to stopping
target
•
S-curve eliminates backgrounds
and sign-selects
• Production: Magnetic bottle traps backward-going π
that can decay into accepted μ’s
Schedule:
2016 for commissioning
• Based on the original MECO
proposal, we believe the experiment
could be operational within 3-4 years
of “CD-2/3a” = begin large, long-lead
time purchases
– Use NOνA experience for time for DOE
–
Approval Process
Use MECO schedule for Technical
Issues, especially solenoid
construction
Thank you!
Quark EM and Color EDMs
LCP


i

c

   q d q  F  d q  G  5q
2 q
i.e. Deuterons and neutrons are sensitive
to different linear combination of quarks
and chromo-EDMs…
The Deuteron is ~20 times more sensitive…
d qqcc
If nEDM is discovered at 10-28 ecm level?
 If q is the source of the EDM, then
dD q /dn q   1/3  dD  3 10 e  cm
29
 If SUSY is the source of the EDM
(isovector part of T - odd N - forces), then
dD q /dn q   20  dD  2 10 e  cm
27
The deuteron EDM is complementary to
neutron and in fact has better sensitivity.
Yannis Semertzidis, BNL
Physics strength comparison
System
Current limit Future goal
[ecm]
Neutron
equivalent
Neutron
<1.6×10-26 ~10-28
10-28
199Hg
atom <2×10-28
~2×10-29
10-25-10-26
129Xe
atom <6×10-27
~10-30-10-33
10-26-10-29
~10-29
3×10-295×10-31
Deuteron
nucleus
Deuteron EDM
• High sensitivity to non-SM CP-violation
• Negligible SM background
• Physics beyond the SM (e.g. SUSY) expect
CP-violation within reach
• Great sensitivity to T-odd Nuclear Forces
• Complementary and better than nEDM
• If observed it will provide a new, large
source of CP-violation that could explain the
Baryon Asymmetry of our Universe (BAU)
Yannis Semertzidis, BNL
Physics strength comparison
System
Current
Future goal
limit [ecm]
Neutron
<1.6×10-
~10-28
10-28
199Hg
atom
<2×10-28
~2×10-29
10-25-10-26
129Xe
<6×10-27
~10-30-10-33
10-26-10-29
~10-29
3×10-295×10-31
26
Neutron
equivalent
atom
Deuteron
nucleus
Yannis Semertzidis, BNL PAC meeting, May 2008
Radium Atom
Electron and Nuclear EDMs
TRIP:
Trapped Radioactive Isotopes:
icro-laboratories for
Fundamental Physics
What about Radium?
• A=88, alkaline earth element
• Ground state [Rn] 7s2 1S0
• No stable isotope
•
226Ra,
1/21600 yrs, 1g RaCl -> Activity of 1Ci
• Interesting isotopes
•
•
•
I=1/2, 1/2  14.7 d
223Ra, I=3/2, 
1/2  15 d
213Ra, I=1/2, 
1/2  2.7 min
225Ra,
Radium Spectroscopy Data
Radium hollow cathode, large grating spectrometer
Ebbe Rasmussen, Z. Phys, 87, 607 , 1934; Z. Phys, 86, 24, 1933.
Resolution ~ 0.05 A, 99 lines. 30 listed in NIST Database
[A]
1S -1P
0
1
1S -3P
0
1
Corrections in deduces energy levels, Level assignment. Some levels shifted by 640 cm-1
H.N. Russel, Phys. Rev. 46, 989 (1934)
Similar to Barium  identification as alkaline earth element
[A]
229Th
7340 yrs

225Ra
15 days

225Ac

10 days
Fr, At, Bi…
~ 4 hours
300 kBcl
229Th
source
ion pump
ion
pump
gate
valve
104 225Ra/s
Offline Setup of 225Ra for Spectroscopy
Ring Alignment (Geometrical
Phases)
~20π rotation
Sz
~π/2 rotation
Yannis Semertzidis, BNL
Sx
Top view of deuteron spin precession in ring.
Optimizing the dEDM search…
Deuteron anomalous moment = – 0.14.
In one revolution, spin lags momentum.
Idea: Use radial electric field to
enlarge orbit and revolution
time while keeping B constant.
Top view of deuteron spin precession in ring.
Optimizing the dEDM search…
Deuteron anomalous moment = – 0.14.
In one revolution, spin lags momentum.
Idea: Use electric field to
enlarge orbit and revolution
time while keeping B constant.
E field
For some ratio of E and B,
the lengthened path will be
just right for the spin to
track the velocity.
(Small precessions will be
used for systematic checks.)
The dEDM ring lattice
0.8m
Bend section (BE)
9m
8.4m
8.4m
Ring circumference: 85m
0.864 m
Straight section (s.s.)
16 free spaces (80cm) in the s.s. per ring
4 places in s.s. reserved for the kicker
1 free space for the RF cavity (normal)
1 free space for theAC-solenoid
2 polarimeters
8 places are free for other needs
Horizontal beam radius (95%):6mm