Light Dark Matter Kenji Kadota IBS Center for Theoretical Physics - PowerPoint PPT Presentation

Light Dark Matter Kenji Kadota IBS Center for Theoretical Physics of the Universe (CTPU) Institute for Basic Science, Korea Ø Two concrete examples ü Sterile neutrino DM Production mechanism ü Axion(-like) Particle Radio (SKA-like) survey Ø Conclusion Kenji Kadota (IBS) YKIS workshop, Feb 2018

� A concrete example for the warm dark matter: Sterile Neutrinos Dodelson-Widrow mechanism: Thermal active neutrinos conversion to sterile neutrinos L = − yNLH − 1 θ = y H 2 MNN M 10 -7 10 -7 10 -7 10 -7 10 -7 10 -7 DM overproduction DM overproduction DM overproduction DM overproduction DM overproduction DM overproduction Interaction strength Sin 2 (2 θ ) Interaction strength Sin 2 (2 θ ) Interaction strength Sin 2 (2 θ ) Interaction strength Sin 2 (2 θ ) Interaction strength Sin 2 (2 θ ) Interaction strength Sin 2 (2 θ ) Excluded by X-ray observations Excluded by X-ray observations Excluded by X-ray observations Excluded by X-ray observations Excluded by X-ray observations Excluded by X-ray observations 10 -8 10 -8 10 -8 10 -8 10 -8 10 -8 Tremaine-Gunn / Lyman- α Tremaine-Gunn / Lyman- α Tremaine-Gunn / Lyman- α Tremaine-Gunn / Lyman- α Tremaine-Gunn / Lyman- α Tremaine-Gunn / Lyman- α 10 -9 10 -9 10 -9 10 -9 10 -9 10 -9 γ e ⌥ 10 -10 10 -10 10 -10 10 -10 10 -10 10 -10 U e N ν e W ± 10 -11 10 -11 10 -11 10 -11 10 -11 10 -11 P P 10 -12 10 -12 10 -12 10 -12 10 -12 10 -12 10 -13 10 -13 10 -13 10 -13 10 -13 10 -13 X X 10 -14 10 -14 10 -14 10 -14 10 -14 10 -14 1 1 1 1 1 1 2 2 2 2 2 2 5 5 5 5 5 5 10 10 10 10 10 10 50 50 50 50 50 50 Drewes et al (2016) Dark matter mass M DM [keV] Dark matter mass M DM [keV] Dark matter mass M DM [keV] Dark matter mass M DM [keV] Dark matter mass M DM [keV] Dark matter mass M DM [keV] Kenji Kadota (IBS) YKIS workshop, Feb 2018

Production from (active-sterile) neutrino oscillation Ω N > Ω DM X-ray Ω N < Ω DM Cherry,Horiuch(2017) Kenji Kadota (IBS) YKIS workshop, Feb 2018

DM constraints heavily depend on the production mechanism! 1) Active-Sterile neutrino oscillation (e.g. Dodelson-Widrow) 2) Active-Sterile neutrino oscillation with the resonance (e.g. Shi-Fuller) 3) Decay of a heavier particle, Thermal freeze-out, variable mixing angle, ... ( e.g. Kusenko, Petraki, Asaka, Shaposhnikov, Merle, Schneider ,Berlin, Hooper,.. ) 4) Sterile-sterile oscillation! (KK and Kaneta (2017)) Also the left-handed neutrino masses via the seesaw mechanism! L = L SM + L N ,  T y ν LH − 1 � T M N ν c ν c 2 ν c L N = ν R i/ R + h.c. ∂ν R − R R Ω N 1 h 2 ∝ sin 2 2 θ N M 1 ( y ν y ν + ) 22 Kenji Kadota (IBS) YKIS workshop, Feb 2018

Light Dark Matter Kenji Kadota IBS Center for Theoretical Physics of the Universe (CTPU) Institute for Basic Science, Korea Ø Two concrete examples ü Sterile neutrino DM Production mechanism ü Axion(-like) Particle Radio (SKA-like) survey Ø Conclusion Kenji Kadota (IBS) YKIS workshop, Feb 2018

10 -6 10 -6 LSW Telescopes VMB ! "## (OSQAR) ' = −𝑕 *++ 𝑏𝑭 - 𝑪 (PVLAS) 𝑏𝐺𝐺 10 -8 10 -8 $ Axion Coupling |G A γγ | (GeV -1 ) Sun Helioscopes (CAST) 10 -10 10 -10 Horizontal Branch Stars HESS Fermi SN 1987A 10 -12 10 -12 Haloscopes (ADMX and others) 10 -14 10 -14 Z V S K PDG (2017) Z S F D 10 -16 10 -16 10 -10 10 -10 10 -8 10 -8 10 -6 10 -6 10 -4 10 -4 10 -2 10 -2 10 0 10 0 Previous work: Axion Mass m A (eV) Relativistic axion converted into photon in presence of B. Figure 61.1: Exclusion plot for axion-like particles as described in the text. Non-relativistic axion decay into two photons for CDM axion. 1 " 1 " 𝑔~ 23 ~240 789 MHz , Axion mass: 0.2~60 𝜈𝑓𝑊 SKA 50MHz-14 GHz, S~𝜈 Jy Line-like radio signal for non-relativistic axion conversion: Non-resonant conversion: Kelley and Quinn (2017), Sigl (2017) Resonant conversion: Huang, KK, Sekiguchi and Tashiro to appear Kenji Kadota (IBS) YKIS workshop, Feb 2018

Square Kilometer Array 
 South Africa- Karoo Australia- Western Outback Construction 2019-2025, Early Science 2022-, Full Science 2025-2030 Cost: ~650 M Euros, Operation ~ 50 M Euros per year. CERN-SKA Big data co-operation agreement Kenji Kadota (IBS) YKIS workshop, Feb 2018

Kelley, Quinn [ApJ Letter (2017)] 10 -6 10 -6 LSW Telescopes VMB (OSQAR) (PVLAS) 10 -8 10 -8 Axion Coupling |G A γγ | (GeV -1 ) Sun Helioscopes (CAST) 10 -10 10 -10 Horizontal Branch Stars HESS Fermi SN 1987A 10 -12 10 -12 Haloscopes (ADMX and others) 10 -14 10 -14 KSVZ DFSZ 10 -16 10 -16 10 -10 10 -10 10 -8 10 -8 10 -6 10 -6 10 -4 10 -4 10 -2 10 -2 10 0 10 0 Kenji Kadota (IBS) YKIS workshop, Feb 2018 Axion Mass m A (eV)

Model: ALP (Axion-like particles) i.e. Ultra-light scalars • Ultra-light mass : DE (Barbieri et al (2005),…) m u ~ H 0 ~ 10 − 33 eV Fuzzy DM (Hu (2000),…) m u ~ 10 − 22 eV String axiverse (Arvanitaki et al (2009),...) m u ~ 10 − 22 eV − 10 − 10 eV m u , f u = Ω u / Ω m ~ O (0.01) m u ≤ H ( t ) : ρ u = const m u > H ( t ) : ρ u ∝ 1 / a 3 KK, Mao, Ichiki, Silk (2014) 10000 P(k)[(Mpc/h) 3 ] 1000 Linear: f u =0 f u =0.05 Nonlinear: f u =0 f u =0.05 100 0.001 0.01 0.1 1 k [h/Mpc] Kenji Kadota (IBS) YKIS workshop, Feb 2018

21 cm signals 1420 MHz Kenji Kadota (IBS) YKIS workshop, Feb 2018

Brief History of Universe Years since the Big Bang ß Big Bang: the Universe is filled with ionized gas ~300000 ß Recombination:The gas cools and becomes neutral (z~1000) Dark Ages ß The first structures begin to form. ~100 million (z~20-40) Reionization starts (z ~12) Reionization ß Reionization is complete ~1 billion (z~6) ~13 billion ß Today ’ s structures (z=0) Kenji Kadota (IBS) YKIS workshop, Feb 2018

What can we do with 21cm? Δ P / P ~ 1/ N High precision on small-scale power spectrum Kleban+(2007) 0.024 m u =1e3 m u =1e5 0.022 m u =1e7 0.02 0.018 0.016 f ν 0.014 0.012 0.01 0.008 0.006 0.004 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 f u KK, Mao, Ichiki, Silk (2014) Kenji Kadota (IBS) Oyama+(2013) YKIS workshop, Feb 2018

Light Dark Matter Kenji Kadota IBS Center for Theoretical Physics of the Universe (CTPU) Institute for Basic Science, Korea Ø Two concrete examples ü Sterile neutrino DM Production mechanism ü Axion(-like) Particle Radio (SKA-like) survey Ø Conclusion Let us be open minded. Complimentarity between particle physics and cosmology. Kenji Kadota (IBS) YKIS workshop, Feb 2018