Ultralight dark matter
Javier RedondoRamón y Cajal fellowUniversidad de Zaragoza (Spain)
Javier Redondo (Zaragoza U)
MIAPP Munich, Dec 1st 2015
Outline
- mass < eV, Fermions, bosons
- Theoretical motivation
- Relic abundance
- Ultralight is different
- Direct Detection
- Laboratory searches
- Indirect Detection ... not much
Low mass bosons (technically natural)
- Pseudo-Goldstone bosons Very generic BSM Axions motivated by the strong CP problem Majorons, familons, etc...
- Axion-like particles in string theories Non-perturbative masses O(100) ALPs in compactifications ... an Axiverse! - Gauge U(1) vector bosons Stuckelberg mass Hidden sectors of string theory?
- The value of controls matter-antimatter differences in QCD✓
Axions and strong CP (bottom up)
✓↵s
8⇡Gµ⌫
eGµ⌫
P, T (CP) violating
✓0 ⇡�⇡
- The value of controls matter-antimatter differences in QCD
n
n
n
n
✓
n
n
Measured today |✓| < 10�10 (strong CP problem)
Axions and strong CP (bottom up)
0 ⇡�⇡
- is it a dynamical field?
n
n
Energy
✓
Measured today |✓| < 10�10 (strong CP problem)
✓(t,x)
generated by QCD!
Axions and strong CP (bottom up)
0 ⇡�⇡
time
n
n
Energy
Measured today |✓| < 10�10 (strong CP problem)
- is it a dynamical field? ✓(t,x)generated by QCD!
✓(t) = ✓0 cos(mat)
Axions and strong CP (bottom up)
0 ⇡�⇡
time
n
n
Energy
~ One parameter theory
axion mass✓(t, x) = a(t, x)/fa
ma = 6meV109 GeV
fa
Measured today |✓| < 10�10 (strong CP problem)
- is it a dynamical field? ✓(t,x)generated by QCD!
✓(t) = ✓0 cos(mat)
Axions and strong CP (bottom up)
0 ⇡�⇡
time
n
nCoherent oscillations
=Dark Matter Axions
Energy
~ One parameter theory
axion mass✓(t, x) = a(t, x)/fa
ma = 6meV109 GeV
fa
Measured today |✓| < 10�10 (strong CP problem)
- is it a dynamical field? ✓(t,x)generated by QCD!
✓(t) = ✓0 cos(mat)
Axions and strong CP (bottom up)
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
ma ' m⇡f⇡fa
' 6 meV109GeV
fa
Mass
1
faa
1
faa
1
faa WISPs
Axion Mass/couplings
Quarks, Photons
Leptons
- Generic interactions for Pseudo-Goldstone bosons- Stringy ALPs, f scale ~ string scale, mass unrelated
New gauge forces : light hidden photons
- Extra hidden U(1)’s (Stückelberg mass)
- Kinetic mixing with photon
- Building blocks in type IIb string theory
� ⇠ egh16⇡2
� �0LI = �1
2�Fµ⌫B
µ⌫
Predictions ...Goodsell 2011
Mass
Mix
ing
Strin
g sc
ale
Cicoli 2011
Anisotropic predictions ...
Mass
Mix
ing
Relic production
Relic production: realignment
- Thermal relics would be hot DM but never enough (recall m<eV)
- Non-thermal mechanisms: realignment from initial conditions
0.001 0.01 0.1 1 10 100 1000-0.5
0.0
0.5
1.0
⇢ ⇠ ⇢0/R(t)3
DUST-likeLambda-like
ak + 3Hak +m2aak ' 0
⇢ = cons
Evolution of decoupled field (zero mode)
t ⇠ 1
ma
✓(t) =a(t)
aI
Relic production: realignment
- Thermal relics would be hot DM but never enough (recall m<eV)
- Non-thermal mechanisms: realignment
Is Predictivity lost? not completely
⇢CDM ' ⇢DM ⇥r
ma
eV
✓aI
4.8⇥ 1011 GeV
◆2
Axio
n
ma / f�1a
aI = faaI ⌧ fa
�⇡
✓
⇡Relic production: topological defects
- After phase transition- random initial conditions- average is predictive
- but topological defects!
- decay into axions uncertain! - Sikivie, Shellard, ... - Kawasaki & al 2014 - Fleury & Moore 2015
�⇡
✓
⇡Relic production: topological defects
- After phase transition- random initial conditions- average is predictive
- but topological defects!
- decay into axions uncertain! - Sikivie, Shellard, ... - Kawasaki & al 2014 - Fleury & Moore 2015
Relic production: topological defects
- After phase transition- random initial conditions- average is predictive
- but topological defects!
- decay into axions uncertain! - Sikivie, Shellard, ... - Kawasaki & al 2014 - Fleury & Moore 2015
Generalisation for ALPs coupled to photons
g ⇠ ↵
2⇡aI
Arias et al 2012
Average models
modelsaI ⌧ fa
Phot
on co
uplin
g
why-not models
ExcludedLab & Astro
Generalisation for ALPs coupled to photons
g ⇠ ↵
2⇡aI
Arias et al 2012
Average models
modelsaI ⌧ fa
Phot
on co
uplin
g
why-not models
ExcludedLab & Astro Unstable
Generalisation for ALPs coupled to photons
g ⇠ ↵
2⇡aI
Arias et al 2012
Average models
modelsaI ⌧ fa
Phot
on co
uplin
g
why-not models
Observable Decays
ExcludedLab & Astro Unstable
Generalisation for ALPs coupled to photons
g ⇠ ↵
2⇡aI
Arias et al 2012
Average models
modelsaI ⌧ fa
Phot
on co
uplin
g
why-not models
Hidden photons : isocurvature dark matter Graham 2015
- Misalignment sourced by Inflation itself
- Longitudinal mode ~ scalar- Except for extra suppression low modes- Compatible with CMB isocurvature constraints- Not possible for axions & ALPs
small scale extra suppression
h|Al|i ⇠HI
2⇡
Hidden photons : isocurvature dark matter Graham 2015
HI ⇠ 1014GeV
- Prediction?, connection of DM abundance with H-Inflation (measurable from B-modes)
HI < 1014GeV
Excluded for HP dark matter (too interacting)
Ultralight is different- DUST-like period before matter-radiation!- Lower limit to the mass CMB distortions
Hlozek 2015
- Ultralight axions (~10^-22 eV) differences in Structure formation (wave interference)
DM fr
actio
n
Schive 2014
- Lengths ~ 1/m- softer cores- low mass halos suppressed- Sikivie’s condensate...
DM Direct detection
10-7 10-6 10-5 10-4 10-310-1
1
10
102
10310-1 1 10 102
10-1
1
10
102
103
c�KSVZ
DFSZ
ADMX
RBF
UF
ADMX AD
MX2 AD
MX-HF
CAR
RACK?
ma[µeV]
⌫[GHz]
IAXO
Cavity experiments
- Dark matter, classical field- Axions, ALPs HPs couple to photons - Modified Electrodynamics (example axions)
r ·D = ⇢f
r⇥H� @D
@t= Jf � c�
↵
2⇡B@✓
@tr ·B = 0
@B
@t+r⇥E = 0
In a magnetised medium
✓(t),�(t), ~A0(t) / cos(mt)
Ea(t) =c�↵✓0B
2⇡✏cos(mat)
|Ea| ⇠ 0.6c� ⇥ 10�30 V
m
- Amplify signal in a MW resonant cavity (Sikivie ‘83)
- Tunable cavity- High B field- Low Temperature (<K)- Low noise pre-amp (<K)
Low signalHigh noise
Cavity experimentsAD
MX
ADM
X-HF
ADM
X-Fe
rmila
b
CULT
ASK
- CAP
P -Ko
rea
CAST
-CAP
P
CARR
ACK
(disc
ontin
ued)
RADE
S
P ⇠ Q|Ea|2(V ma)G
P ⇠ |Ea|2A
Q ⇠ 104 ⇠ Am2acomparable if
Dish antenna
E-fie
ld ex
cites
mirr
or to
emit
phot
ons
Dish antenna for Hidden PhotonsTo
kyo
Expe
rimen
tsKa
rsruh
e FUN
K
visible
MW
Enhanced mirror with dielectric layers
E-fie
ld ex
cites
mirr
or to
emit
phot
ons P ⇠ |Ea|2A⇥ � boost
- Just a mirror is not good enough for axions ...- Use many (mirror configuration, cavity configuration)
Oscillating electric dipole moment (axion DM)
dn ⇠ 10
�35cos(mat)e cm
- Mainz (D. Budker’s group) & Berkeley- B-field, coherence time, sensitivity to m < neV- Phase I starts in 2016, Phase II physics results
EDM + Large E-fields in PbTiO3
Stars as Laboratories
⌫, ⌫ �
WISPs ?
Stellar cooling Numerical simulations vs. Observations
- Strong constraints (Sun, SN1987A, WDs, RG, HB ...)- But slight preferences for meV-mass axions (electron/neutron coupling) Luminosity of brightest Red Giant White dwarf luminosity F CAS A cooling
Viaux 2013 Bertolami 2014 Stetson 2014
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : Axions
Solar Axions 5th forces Photon regeneration
IAXO CDR 2014 Arvanitaki Geraci PRL 2014 ALPS-II TDR 2013
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Laboratory searches : HPs
Coulomb’s law Photon regeneration
SHIPS, DM detectors XENON10 Williams ... 1971 ALPS-II, MW cavities
Solar HPs
Indirect detection
- Axions, ALPs, HPs are not stable
- Decay lifetime very long (sub-eV)- Annihilation negligible
- But inhomogeneous DM, axion miniclusters, HP clumps- Annihilation in a neutron star ... Fast Radio Bursts?
a ! �� , �0 ! ���
Zurek et al 07, See also Kolb & Tkachev 94
Iwazaki; Tkachev , 2014
Conclusions
- Axions, Axion-likes, Hidden Photons make good dark matter
- Bottom-up and Top-bottom motivation
- Relic abundance : realignment and topological defects
- Ultralight is different : hyperlow mass effects in structure formation
- Direct Detection: key target areas not completely covered
- Laboratory searches,
- Indirect Detection ... not much
Axion DM : A developing picture
osc. EDM
IAXO DM
IAXO DM
Dish Antenna?
CAPP
5th forces?
ADMXADMX-HF