Variation of the Fundamental Constants
produced by Dark Matter and Exotic Bosons
Yevgeny Stadnik, Victor Flambaum
Johannes Gutenberg University, Mainz, Germany
University of New South Wales, Sydney, Australia
PRL 113, 081601 (2014); PRL 113, 151301 (2014);
PRL 114, 161301 (2015); PRL 115, 201301 (2015);
PRL 117, 271601 (2016);
PRD 89, 043522 (2014); PRD 90, 096005 (2014);
EPJC 75, 110 (2015); PRA 93, 063630 (2016);
PRD 93, 115037 (2016); PRA 94, 022111 (2016).
International Conference on Precision Physics and Fundamental Physical
Constants, Warsaw, May 2017
Motivation
Overwhelming astrophysical evidence for existence
of dark matter (~5 times more dark matter than
ordinary matter).
Motivation
Overwhelming astrophysical evidence for existence
of dark matter (~5 times more dark matter than
ordinary matter).
– “What is dark matter and how does it interact with
ordinary matter non-gravitationally?”
Motivation
Traditional “scattering-off-nuclei” searches for
heavy WIMP dark matter particles (mχ ~ GeV) have
not yet produced a strong positive result.
Motivation
Traditional “scattering-off-nuclei” searches for
heavy WIMP dark matter particles (mχ ~ GeV) have
not yet produced a strong positive result.
Motivation
Traditional “scattering-off-nuclei” searches for
heavy WIMP dark matter particles (mχ ~ GeV) have
not yet produced a strong positive result.
Motivation
Traditional “scattering-off-nuclei” searches for
heavy WIMP dark matter particles (mχ ~ GeV) have
not yet produced a strong positive result.
Problem: Observable is quartic in the interaction
constant e‫י‬, which is extremely small (e‫ << י‬1)!
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
• Classical field for mφ ≤ 0.1 eV, since nφ(λdB/2π)3 >> 1
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
• Classical field for mφ ≤ 0.1 eV, since nφ(λdB/2π)3 >> 1
• Coherent + classical DM field = “Cosmic laser”
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
• Classical field for mφ ≤ 0.1 eV, since nφ(λdB/2π)3 >> 1
• Coherent + classical DM field = “Cosmic laser”
• 10-22 eV ≤ mφ ≤ 0.1 eV <=> 10-8 Hz ≤ f ≤ 1013 Hz
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
• Classical field for mφ ≤ 0.1 eV, since nφ(λdB/2π)3 >> 1
• Coherent + classical DM field = “Cosmic laser”
• 10-22 eV ≤ mφ ≤ 0.1 eV <=> 10-8 Hz ≤ f ≤ 1013 Hz
• mφ ~ 10-22 eV DM can resolve several long-standing “smallscale crises” of the cold DM model
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• Coherently oscillating field, since cold (Eφ ≈ mφc2)
• Classical field for mφ ≤ 0.1 eV, since nφ(λdB/2π)3 >> 1
• Coherent + classical DM field = “Cosmic laser”
• 10-22 eV ≤ mφ ≤ 0.1 eV <=> 10-8 Hz ≤ f ≤ 1013 Hz
• mφ ~ 10-22 eV DM can resolve several long-standing “smallscale crises” of the cold DM model
• f ~ 10-8 Hz (mφ ~ 10-22 eV) <=> T ~ 1 year
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• 10-22 eV ≤ mφ ≤ 0.1 eV inaccessible to traditional “scatteringoff-nuclei” searches, since |pφ| ~ 10-3mφ is extremely small
=> recoil effects suppressed
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• 10-22 eV ≤ mφ ≤ 0.1 eV inaccessible to traditional “scatteringoff-nuclei” searches, since |pφ| ~ 10-3mφ is extremely small
=> recoil effects suppressed
• BUT can look for novel effects of low-mass DM in low-energy
atomic and astrophysical phenomena that are linear in the
interaction constant κ :
Low-mass Spin-0 Dark Matter
• Low-mass spin-0 particles form a coherently oscillating
classical field φ(t) = φ0 cos(mφc2t/ℏ), with energy density
<ρφ> ≈ mφ2φ02/2 (ρDM,local ≈ 0.4 GeV/cm3)
• 10-22 eV ≤ mφ ≤ 0.1 eV inaccessible to traditional “scatteringoff-nuclei” searches, since |pφ| ~ 10-3mφ is extremely small
=> recoil effects suppressed
• BUT can look for novel effects of low-mass DM in low-energy
atomic and astrophysical phenomena that are linear in the
interaction constant κ :
• Consideration of linear effects => Improved sensitivity to
certain DM interactions by up to 15 orders of magnitude (!)
Low-mass Spin-0 Dark Matter
Dark Matter
Low-mass Spin-0 Dark Matter
Dark Matter
Scalars
(Dilatons):
φ(-x) = +φ(x)
Low-mass Spin-0 Dark Matter
Dark Matter
Scalars
(Dilatons):
φ(-x) = +φ(x)
Pseudoscalars
(Axions):
φ(-x) = -φ(x)
Low-mass Spin-0 Dark Matter
Dark Matter
Scalars
(Dilatons):
φ(-x) = +φ(x)
→ Time-varying
fundamental constants
Pseudoscalars
(Axions):
φ(-x) = -φ(x)
Low-mass Spin-0 Dark Matter
Dark Matter
Scalars
(Dilatons):
φ(-x) = +φ(x)
→ Time-varying
fundamental constants
Pseudoscalars
(Axions):
φ(-x) = -φ(x)
→ Time-varying spindependent effects
Low-mass Spin-0 Dark Matter
Dark Matter
Scalars
(Dilatons):
φ(-x) = +φ(x)
→ Time-varying
fundamental constants
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
• Possible models for cosmological evolution of
fundamental constants?
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
• Possible models for cosmological evolution of
fundamental constants?
Dark energy (mφ ≈ 0)
Slow rolling (t ~ t Universe)
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
• Possible models for cosmological evolution of
fundamental constants?
Dark energy (mφ ≈ 0)
Dark matter?
φ(t) = φ0 cos(mφt)
Slow rolling (t ~ t Universe)
Rapid oscillations (t << t Universe)
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
• Possible models for cosmological evolution of
fundamental constants?
Dark energy (mφ ≈ 0)
Dark matter?
φ(t) = φ0 cos(mφt)
<φ> = 0
Slow rolling (t ~ t Universe)
Rapid oscillations (t << t Universe)
Cosmological Evolution of the
Fundamental Constants
• Dirac’s large numbers hypothesis: G ∝ 1/t
• Fundamental constants not predicted from theory, but
determined from measurements (local – not universal)
• Possible models for cosmological evolution of
fundamental constants?
Dark energy (mφ ≈ 0)
Dark matter?
φ(t) = φ0 cos(mφt)
<φ> = 0
<φ2> = φ02/2 ∝ ρφ
Slow rolling (t ~ t Universe)
Rapid oscillations (t << t Universe)
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
‘Slow’ drifts [Astrophysics
(high ρDM): BBN, CMB]
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Consider quadratic couplings of an oscillating classical
scalar field, φ(t) = φ0 cos(mφt), with SM fields.
‘Slow’ drifts [Astrophysics
Oscillating variations
(high ρDM): BBN, CMB]
[Laboratory (high precision)]
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Fermions:
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Fermions:
Photon:
Dark Matter-Induced Cosmological
Evolution of the Fundamental Constants
[Stadnik, Flambaum, PRL 114, 161301 (2014); PRL 115, 201301 (2015)]
Fermions:
Photon:
W and Z Bosons:
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
• Big Bang nucleosynthesis (tweak ≈ 1s – tBBN ≈ 3 min)
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
• Big Bang nucleosynthesis (tweak ≈ 1s – tBBN ≈ 3 min)
• Primordial 4He abundance sensitive to n/p ratio
(almost all neutrons bound in 4He after BBN)
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
• Big Bang nucleosynthesis (tweak ≈ 1s – tBBN ≈ 3 min)
• Primordial 4He abundance sensitive to n/p ratio
(almost all neutrons bound in 4He after BBN)
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
• Big Bang nucleosynthesis (tweak ≈ 1s – tBBN ≈ 3 min)
• Primordial 4He abundance sensitive to n/p ratio
(almost all neutrons bound in 4He after BBN)
BBN Constraints on ‘Slow’ Drifts in
Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 115, 201301 (2015)]
• Largest effects of DM in early Universe (highest ρDM)
• Big Bang nucleosynthesis (tweak ≈ 1s – tBBN ≈ 3 min)
• Primordial 4He abundance sensitive to n/p ratio
(almost all neutrons bound in 4He after BBN)
Atomic Spectroscopy Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Arvanitaki, Huang, Van Tilburg, PRD 91, 015015 (2015)], [Stadnik, Flambaum, PRL 114, 161301 (2015)]
ω = mφ (linear portal) or ω = 2mφ (quadratic portal)
Atomic Spectroscopy Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Arvanitaki, Huang, Van Tilburg, PRD 91, 015015 (2015)], [Stadnik, Flambaum, PRL 114, 161301 (2015)]
ω = mφ (linear portal) or ω = 2mφ (quadratic portal)
• Precision of optical clocks approaching ~10-18 fractional level
Atomic Spectroscopy Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Arvanitaki, Huang, Van Tilburg, PRD 91, 015015 (2015)], [Stadnik, Flambaum, PRL 114, 161301 (2015)]
ω = mφ (linear portal) or ω = 2mφ (quadratic portal)
• Precision of optical clocks approaching ~10-18 fractional level
• Sensitivity coefficients KX calculated extensively by
Flambaum group and co-workers (1998 – present)
Atomic Spectroscopy Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Arvanitaki, Huang, Van Tilburg, PRD 91, 015015 (2015)], [Stadnik, Flambaum, PRL 114, 161301 (2015)]
ω = mφ (linear portal) or ω = 2mφ (quadratic portal)
• Precision of optical clocks approaching ~10-18 fractional level
• Sensitivity coefficients KX calculated extensively by
Flambaum group and co-workers (1998 – present)
Dy/Cs: [Van Tilburg et al., PRL 115, 011802 (2015)], [Stadnik, Flambaum, PRL 115, 201301 (2015)]
Atomic Spectroscopy Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Arvanitaki, Huang, Van Tilburg, PRD 91, 015015 (2015)], [Stadnik, Flambaum, PRL 114, 161301 (2015)]
ω = mφ (linear portal) or ω = 2mφ (quadratic portal)
• Precision of optical clocks approaching ~10-18 fractional level
• Sensitivity coefficients KX calculated extensively by
Flambaum group and co-workers (1998 – present)
Dy/Cs: [Van Tilburg et al., PRL 115, 011802 (2015)], [Stadnik, Flambaum, PRL 115, 201301 (2015)]
Rb/Cs: [Hees et al., PRL 117, 061301 (2016)], [Stadnik, Flambaum, PRA 94, 022111 (2016)]
Laser Interferometry Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 114, 161301 (2015); PRA 93, 063630 (2016)]
LIGO interferometer,
L ~ 4 km
Small-scale cavity,
L ~ 0.2 m
Laser Interferometry Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 114, 161301 (2015); PRA 93, 063630 (2016)]
• Compare L ~ NaB with λ
Laser Interferometry Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 114, 161301 (2015); PRA 93, 063630 (2016)]
• Compare L ~ NaB with λ
Laser Interferometry Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 114, 161301 (2015); PRA 93, 063630 (2016)]
• Compare L ~ NaB with λ
• Enhancement of effect due to multiple reflections of
light beam (Neff ~ 105 in small-scale interferometers with
highly reflective mirrors)
Laser Interferometry Searches for Oscillating Variations
in Fundamental Constants due to Dark Matter
[Stadnik, Flambaum, PRL 114, 161301 (2015); PRA 93, 063630 (2016)]
• Compare L ~ NaB with λ
• Enhancement of effect due to multiple reflections of
light beam (Neff ~ 105 in small-scale interferometers with
highly reflective mirrors)
Sr/Cavity (Domain wall DM): [Wcislo et al., Nature Astronomy 1, 0009 (2016)]
Constraints on Quadratic Interaction of
Scalar Dark Matter with the Photon
BBN, CMB, Dy and Rb/Cs constraints:
[Stadnik, Flambaum, PRL 115, 201301 (2015); PRA 94, 022111 (2016)]
15 orders of magnitude improvement!
Low-mass Spin-0 Dark Matter
Dark Matter
QCD axion resolves
strong CP problem
Pseudoscalars
(Axions):
φ(-x) = -φ(x)
→ Time-varying spindependent effects
“Axion Wind” Spin-Precession Effect
[Flambaum, talk at Patras Workshop, 2013], [Graham, Rajendran, PRD 88, 035023 (2013)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Pseudo-magnetic field
Axion-Induced Oscillating Spin-Gravity Coupling
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Distortion of DM field by
massive body
Oscillating Electric Dipole Moments
Electric Dipole Moment (EDM) = parity (P) and timereversal-invariance (T) violating electric moment
Axion-Induced Oscillating Neutron EDM
[Crewther, Di Vecchia, Veneziano, Witten, PLB 88, 123 (1979)],
[Pospelov, Ritz, PRL 83, 2526 (1999)], [Graham, Rajendran, PRD 84, 055013 (2011)]
Schiff’s Theorem
[Schiff, Phys. Rev. 132, 2194 (1963)]
Schiff’s Theorem: “In a neutral atom made up of point-like nonrelativistic charged particles (interacting only electrostatically), the
constituent EDMs are screened from an external electric field.”
Schiff’s Theorem
[Schiff, Phys. Rev. 132, 2194 (1963)]
Schiff’s Theorem: “In a neutral atom made up of point-like nonrelativistic charged particles (interacting only electrostatically), the
constituent EDMs are screened from an external electric field.”
Classical explanation for nuclear EDM: A neutral atom does not
accelerate in an external electric field!
Schiff’s Theorem
[Schiff, Phys. Rev. 132, 2194 (1963)]
Schiff’s Theorem: “In a neutral atom made up of point-like nonrelativistic charged particles (interacting only electrostatically), the
constituent EDMs are screened from an external electric field.”
Classical explanation for nuclear EDM: A neutral atom does not
accelerate in an external electric field!
Schiff’s Theorem
[Schiff, Phys. Rev. 132, 2194 (1963)]
Schiff’s Theorem: “In a neutral atom made up of point-like nonrelativistic charged particles (interacting only electrostatically), the
constituent EDMs are screened from an external electric field.”
Classical explanation for nuclear EDM: A neutral atom does not
accelerate in an external electric field!
Schiff’s Theorem
[Schiff, Phys. Rev. 132, 2194 (1963)]
In real atoms: Incomplete screening of external electric field due to
finite nuclear size, parametrised by nuclear Schiff moment.
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
•
Oscillating nuclear Schiff moments (I ≥ 1/2 => J ≥ 0)
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
•
Oscillating nuclear Schiff moments (I ≥ 1/2 => J ≥ 0)
•
Oscillating nuclear magnetic quadrupole moments
(I ≥ 1 => J ≥ 1/2; magnetic => no Schiff screening)
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
•
Oscillating nuclear Schiff moments (I ≥ 1/2 => J ≥ 0)
•
Oscillating nuclear magnetic quadrupole moments
(I ≥ 1 => J ≥ 1/2; magnetic => no Schiff screening)
Underlying mechanisms:
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
•
Oscillating nuclear Schiff moments (I ≥ 1/2 => J ≥ 0)
•
Oscillating nuclear magnetic quadrupole moments
(I ≥ 1 => J ≥ 1/2; magnetic => no Schiff screening)
Underlying mechanisms:
(1) Intrinsic oscillating nucleon EDMs (1-loop level)
(1)
Axion-Induced Oscillating Atomic and Molecular EDMs
[O. Sushkov, Flambaum, Khriplovich, JETP 60, 873 (1984)],
[Stadnik, Flambaum, PRD 89, 043522 (2014)]
Induced through hadronic mechanisms:
•
Oscillating nuclear Schiff moments (I ≥ 1/2 => J ≥ 0)
•
Oscillating nuclear magnetic quadrupole moments
(I ≥ 1 => J ≥ 1/2; magnetic => no Schiff screening)
Underlying mechanisms:
(1) Intrinsic oscillating nucleon EDMs (1-loop level)
(2) Oscillating P,T-violating intranuclear forces (tree level => larger
by ~4π2 ≈ 40; additional enhancement in deformed nuclei)
(1)
(2)
Axion-Induced Oscillating Atomic and Molecular EDMs
[Stadnik, Flambaum, PRD 89, 043522 (2014)], [Roberts, Stadnik, Dzuba, Flambaum,
Leefer, Budker, PRL 113, 081601 (2014); PRD 90, 096005 (2014)]
Also induced through non-hadronic mechanisms for J ≥ 1/2 atoms,
via mixing of opposite-parity atomic states.
Searching for Spin-Dependent Effects
Need spin-polarised sources!
Searching for Spin-Dependent Effects
Need spin-polarised sources!
n/Hg: [nEDM collaboration (Ayres, Harris, Kirch, Rawlik et al.), Flambaum, Stadnik, In preparation]
Searching for Spin-Dependent Effects
Need spin-polarised sources!
n/Hg: [nEDM collaboration (Ayres, Harris, Kirch, Rawlik et al.), Flambaum, Stadnik, In preparation]
Searching for Spin-Dependent Effects
Need spin-polarised sources!
n/Hg: [nEDM collaboration (Ayres, Harris, Kirch, Rawlik et al.), Flambaum, Stadnik, In preparation]
Searching for Spin-Dependent Effects
Need spin-polarised sources!
n/Hg: [nEDM collaboration (Ayres, Harris, Kirch, Rawlik et al.), Flambaum, Stadnik, In preparation]
Constraints on Interaction of Axion
Dark Matter with Gluons
n/Hg constraints: [nEDM collaboration, In preparation]
3 orders of magnitude improvement!
Conclusions
• New classes of dark matter effects that are linear in
the underlying interaction constant (usual effects are
either quadratic or quartic)
Conclusions
• New classes of dark matter effects that are linear in
the underlying interaction constant (usual effects are
either quadratic or quartic)
• Up to 15 orders of magnitude improvement in
sensitivity on certain dark matter interactions, and
first limits on other interactions
Conclusions
• New classes of dark matter effects that are linear in
the underlying interaction constant (usual effects are
either quadratic or quartic)
• Up to 15 orders of magnitude improvement in
sensitivity on certain dark matter interactions, and
first limits on other interactions
• Enormous potential for future experiments
Conclusions
• New classes of dark matter effects that are linear in
the underlying interaction constant (usual effects are
either quadratic or quartic)
• Up to 15 orders of magnitude improvement in
sensitivity on certain dark matter interactions, and
first limits on other interactions
• Enormous potential for future experiments
• New results soon!