Dark Radiation Constraints on Mixed Axion/Neutralino Dark Matter André Lessa University of São Paulo Moriond - March 11th, 2013 H. Baer, K. J. Bae, AL, arXiv:1301.7428 Outline What is Dark Radiation? Axions and Dark Radiation Supersymmetric Axion CMB Constraints Conclusions What is Dark Radiation? What is Dark Radiation? ◮ Number of relativistic species during matter-radiation decoupling (T ∼eV): ρR = ργ + Nν ρν + ??? "Radiation" Neutrinos Dark Radiation What is Dark Radiation? ◮ Number of relativistic species during matter-radiation decoupling (T ∼eV): ρR = ργ + Nν ρν + ??? "Radiation" Neutrinos Dark Radiation ◮ N Nν ρν +ρX 3 04 Or: eff = ρν → . (SM) What is Dark Radiation? ◮ Number of relativistic species during matter-radiation decoupling (T ∼eV): ρR = ργ + Nν ρν + ??? "Radiation" Neutrinos Dark Radiation ◮ N Nν ρν +ρX 3 04 Or: eff = ρν → . (SM) 6000 Neff and CMB: 5000 ) 2 Neff = 2 • Affects expansion rate K µ 4000 N = 3.04 ) ( eff → shifts peak π /(2 N = 4.34 3000 eff • Changes time of matter-radiation equality TT l → enhances 1st and 2nd peaks 2000 l(l+1)C • ... 1000 102 103 Multipole Moment (l) Dark Radiation 2011: WMAP7 Neff = 4.34 ± 0.88 arXiv:1212.5226 SPT Neff = 3.86 ± 0.42 ACT Neff = 4.6 ± 0.80 2012-2013: WMAP9 Neff = 3.84 ± 0.40 WMAP9 NSPT 3 71 ± 0 35 SPT eff = . ACT ACT Neff = 3.50 ± 0.42 2013-: Planck Neff =?? ± 0.2 Dark Radiation 2011: WMAP7 Neff = 4.34 ± 0.88 arXiv:1212.5226 SPT Neff = 3.86 ± 0.42 ACT Neff = 4.6 ± 0.80 2012-2013: WMAP9 Neff = 3.84 ± 0.40 WMAP9 NSPT 3 71 ± 0 35 SPT eff = . ACT ACT Neff = 3.50 ± 0.42 2013-: Planck Neff =?? ± 0.2 SM → ✞∆Neff ≡ Neff − Neff < 1.6 (95% C.L.) ☎ ✝ ✆ Dark Radiation 2011: WMAP7 Neff = 4.34 ± 0.88 arXiv:1212.5226 SPT Neff = 3.86 ± 0.42 ACT Neff = 4.6 ± 0.80 2012-2013: WMAP9 Neff = 3.84 ± 0.40 WMAP9 NSPT 3 71 ± 0 35 SPT eff = . ACT ACT Neff = 3.50 ± 0.42 2013-: Planck Neff =?? ± 0.2 SM → ✞∆Neff ≡ Neff − Neff < 1.6 (95% C.L.) ☎ ✝ ✆ ◮ What if the excess is real? Dark Radiation 2011: WMAP7 Neff = 4.34 ± 0.88 arXiv:1212.5226 SPT Neff = 3.86 ± 0.42 ACT Neff = 4.6 ± 0.80 2012-2013: WMAP9 Neff = 3.84 ± 0.40 WMAP9 NSPT 3 71 ± 0 35 SPT eff = . ACT ACT Neff = 3.50 ± 0.42 2013-: Planck Neff =?? ± 0.2 SM → ✞∆Neff ≡ Neff − Neff < 1.6 (95% C.L.) ☎ ✝ ✆ ◮ What if the excess is real? • New relativistic species at T & eV • mDR . eV (usually) → suppressed interactions with SM Dark Radiation 2011: WMAP7 Neff = 4.34 ± 0.88 arXiv:1212.5226 SPT Neff = 3.86 ± 0.42 ACT Neff = 4.6 ± 0.80 2012-2013: WMAP9 Neff = 3.84 ± 0.40 WMAP9 NSPT 3 71 ± 0 35 SPT eff = . ACT ACT Neff = 3.50 ± 0.42 2013-: Planck Neff =?? ± 0.2 SM → ✞∆Neff ≡ Neff − Neff < 1.6 (95% C.L.) ☎ ✝ ✆ ◮ What if the excess is real? • New relativistic species at T & eV • mDR . eV (usually) → suppressed interactions with SM • DR candidates: (light) sterile neutrinos, gravitinos, axions, ... Axion = Dark Radiation? ◮ QCD axion (Strong CP Problem) 6 ◮ 10 GeV ma ∼ 6 eV fa g ◮ 9 fa & 10 GeV (astrophysical bounds) a αs ∝ ✔ fa → ma . meV g → small couplings ✔ Axion = Dark Radiation? ◮ QCD axion (Strong CP Problem) 6 ◮ 10 GeV ma ∼ 6 eV fa g ◮ 9 fa & 10 GeV (astrophysical bounds) a αs ∝ ✔ fa → ma . meV g → small couplings ✔ ◮ Coherent Oscillations → CDM Axion = Dark Radiation? ◮ QCD axion (Strong CP Problem) 6 ◮ 10 GeV ma ∼ 6 eV fa g ◮ 9 fa & 10 GeV (astrophysical bounds) a αs ∝ ✔ fa → ma . meV g → small couplings ✔ ◮ Coherent Oscillations → CDM ◮ Also produced thermally: g a Relativistic ✔ g g g Axion = Dark Radiation? ◮ QCD axion (Strong CP Problem) 6 ◮ 10 GeV ma ∼ 6 eV fa g ◮ 9 fa & 10 GeV (astrophysical bounds) a αs ∝ ✔ fa → ma . meV g → small couplings ✔ ◮ Coherent Oscillations → CDM ◮ Also produced thermally: g a Relativistic ✔ −2 g → ✞∆Neff < 10 ☎→ Below CMB sensitivity g g (Can✝ not explain possible✆ excess) Axion = Dark Radiation? ◮ QCD axion (Strong CP Problem) 6 ◮ 10 GeV ma ∼ 6 eV fa g ◮ 9 fa & 10 GeV (astrophysical bounds) a αs ∝ ✔ fa → ma . meV g → small couplings ✔ ◮ Coherent Oscillations → CDM ◮ Also produced thermally: g a Relativistic ✔ −2 g → ✞∆Neff < 10 ☎→ Below CMB sensitivity g g (Can✝ not explain possible✆ excess) ◮ Non-thermal production? Supersymmetric Axion ◮ fa ≫ EW scale → Hierarchy Problem → Supersymmetry Supersymmetric Axion ◮ fa ≫ EW scale → Hierarchy Problem → Supersymmetry ◮ Supersymmetric Axion: a → Aˆ → s + i a + a˜ saxion axion axino • SM + a → MSSM + a, s, a˜ = PQMSSM Supersymmetric Axion ◮ fa ≫ EW scale → Hierarchy Problem → Supersymmetry ◮ Supersymmetric Axion: a → Aˆ → s + i a + a˜ saxion axion axino • SM + a → MSSM + a, s, a˜ = PQMSSM • Couplings: g g g˜ g a → a, s s a˜ g g g˜ g˜ a˜ a + s s a˜ a Supersymmetric Axion ◮ fa ≫ EW scale → Hierarchy Problem → Supersymmetry ◮ Supersymmetric Axion: a → Aˆ → s + i a + a˜ saxion axion axino • SM + a → MSSM + a, s, a˜ = PQMSSM • Couplings: g g g˜ g a → a, s s a˜ g g g˜ g˜ a˜ ✛ a✘ + s s → Non-thermal axion production (if ms > 2ma) a˜ a ✚ ✙ Supersymmetric Axion ◮ PQMSSM Masses: PQMSSM q˜1,2, ˜l Mass Scale g˜ ˜t, b˜ LSP SM Supersymmetric Axion ◮ PQMSSM Masses: PQMSSM q˜1,2, ˜l s Mass Scale g˜ ˜t, b˜ LSP SM Supersymmetric Axion ◮ PQMSSM Masses: PQMSSM q˜1,2, ˜l s Mass Scale g˜ ˜t, b˜ LSP SM a Supersymmetric Axion ◮ PQMSSM Masses: PQMSSM q˜1,2, ˜l s a˜ Mass Scale g˜ ˜t, b˜ LSP SM We assume: a mLSP = me < m . ms ∼ mSUSY Z1 a˜ Supersymmetric Axion s → a + a ◮ PQMSSM Masses: 1 PQMSSM 10-1 s → ~a + ~a q˜1 2, ˜l , 10-2 s BF a˜ s → g + g Mass Scale -3 g˜ 10 m = 1.6 TeV ~g s → ~g + ~g ˜ -4 ˜t, b 10 m~a = 0.5 TeV LSP 10-5 3 4 SM 10 10 ms (GeV) We assume: a mLSP = me < m . ms ∼ mSUSY Z1 a˜ Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) ◮ Dark Radiation = Axions Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) ◮ Dark Radiation = Axions • Production: TP s → a + a Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) ◮ Dark Radiation = Axions • Production: TP s → a + a • ∆Neff & 1 → large saxion production Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) ◮ Dark Radiation = Axions • Production: TP s → a + a • ∆Neff & 1 → large saxion production • CMB constrains saxion production! Supersymmetric Axion ◮ Dark Matter = Neutralino + Axions • Neutralino production: TP (∼ MSSM) e a˜ → g + g˜ → ...Z1 + X • Axion production: coherent oscillations (CDM) ◮ Dark Radiation = Axions • Production: TP s → a + a • ∆Neff & 1 → large saxion production • CMB constrains saxion production! How are saxions produced in the early universe? Saxion Production ◮ Thermal Production g s TP 2 g → ρs ∝ TR/fa g g g a˜ TP 2 g → ρa˜ ∝ TR/fa g g˜ Saxion Production ◮ Thermal Production ◮ Coherent Oscillations: g s TP 2 → ρ ∝ TR/f g s a CO 2 2 → ρs ∝ θs fa g g • θs is UV dependent (inflation) g a˜ (θsfa ≡ s0) TP 2 g → ρa˜ ∝ TR/fa g g˜ Saxion Production ◮ Thermal Production ◮ Coherent Oscillations: g s TP 2 → ρ ∝ TR/f g s a CO 2 2 → ρs ∝ θs fa g g • θs is UV dependent (inflation) g a˜ (θsfa ≡ s0) • TP 2 Dominates at large fa and low TR g → ρa˜ ∝ TR/fa g g˜ • Dominates at small fa and high TR CMB Constraints on TP ◮ Thermal Production of Saxions: 102 ∆ 10 CMB Excluded ( Neff > 1.6) 1 s(TP) 10-1 eff N -2 ∆ 10 10-3 10-4 10-5 107 108 109 1010 1011 1012 1013 T R (GeV) • Saxion production increases with TR CMB Constraints on TP ◮ Thermal Production of Saxions: 102 ∆ 10 CMB Excluded ( Neff > 1.6) 1 s(TP) 10-1 eff N -2 ∆ 10 10-3 10-4 10-5 107 108 109 1010 1011 1012 1013 T R (GeV) • Saxion production increases with TR ...but axino production increases at the same rate! CMB Constraints on TP ◮ Thermal Production of Saxions: 102 ∆ 10 CMB Excluded ( Neff > 1.6) 1 s(TP) 10-1 eff N -2 ∆ 10 10-3 10-4 10-5 107 108 109 1010 1011 1012 1013 T R (GeV) • Saxion production increases with TR ...but axino production increases at the same rate! ρ(s→aa) ∆Neff ∼ e ργ +ρ(a˜→Z1+γ) CMB Constraints on TP ◮ Thermal Production of Saxions: 102 ∆ 10 CMB Excluded ( Neff > 1.6) 1 s(TP) 10-1 eff N -2 ∆ 10 s(TP) + ~a(TP) 10-3 10-4 10-5 107 108 109 1010 1011 1012 1013 T R (GeV) • Saxion production increases with TR ...but axino production increases at the same rate! ρ(s→aa) ρ(s→aa) ∆Neff ∼ e → e ργ +ρ(a˜→Z1+γ) ρ(a˜→Z1+γ) CMB Constraints on TP ◮ Thermal Production of Saxions: 102 ∆ 10 CMB Excluded ( Neff > 1.6) 1 s(TP) 10-1 eff N -2 ∆ 10 s(TP) + ~a(TP) 10-3 10-4 10-5 107 108 109 1010 1011 1012 1013 T R (GeV) • Saxion production increases with TR ...but axino production increases at the same rate! ρ(s→aa) ρ(s→aa) ∆Neff ∼ e → e .