Discovering Inelastic Thermal Dark Matter Gordan Krnjaic + Eder - PowerPoint PPT Presentation

Discovering Inelastic Thermal Dark Matter Gordan Krnjaic + Eder Izaguirre, Yonatan Kahn, Matthew Moschella 1703.06881 + Eder Izaguirre, Brian Shuve 1508.03050 Cosmic Visions, UMD March 24, 2017

Thermal Equilibrium Thermal Contact Narrows Mass Range Advantage #2: Narrows Mass Range m DM nonthermal nonthermal ∼ 10 − 20 eV ∼ 100 M � m P l ∼ 10 19 GeV < 10 keV < MeV > 100 TeV GeV m Z MeV { too much { too hot Neff / BBN Light DM “WIMPs” Direct Detection (Alan Robinson) Indirect Detection (Alex Drlica-Wagner) Colliders (Yang Bai) 2 18

CMB Bounds for light DM Rules out s -wave annihilation < 10 GeV 10 − 23 Planck TT,TE,EE+lowP WMAP9 CVL Possible interpretations for: For viable models need: 10 − 24 f e ff � σ v � [cm 3 s − 1 ] AMS-02/Fermi/Pamela Fermi GC 10 − 25 (1) p-wave annihilation OR Thermal relic 10 − 26 Planck (2) annihilation shuts off 10 − 27 1303.5076 before CMB 1 10 100 1000 10000 m χ [GeV] 3

CMB Bounds for light DM Rules out s -wave annihilation < 10 GeV 10 − 23 Planck TT,TE,EE+lowP WMAP9 CVL Possible interpretations for: For viable models need: 10 − 24 f e ff � σ v � [cm 3 s − 1 ] AMS-02/Fermi/Pamela Fermi GC 10 − 25 (1) p-wave annihilation OR Thermal relic 10 − 26 Planck (2) annihilation shuts off 10 − 27 1303.5076 before CMB 1 10 100 1000 10000 m χ [GeV] 4

Inelastic DM is CMB Safe Direct Coannihilation into SM SM χ 1 ∆ ⌘ m χ 2 � m χ 1 � eV SM χ 2 Heavier state disappears before z ~1100 n χ 2 ∼ e − ∆ /T No indirect detection No (tree level) direct detection ∆ > 100 keV Easy to build, large couplings, hard to test! iDM direct detection: Weiner, Tucker-Smith arXiv: 0101338

Example Model Four component fermion + familiar dark photon ψγ µ ψ + M ¯ ψ c ψ µ ¯ ψψ + H D ¯ L ⊃ g D A 0 Charge 2 Dirac Vector mass current dark Higgs

Example Model Four component fermion + familiar dark photon ψγ µ ψ + M ¯ ψ c ψ µ ¯ ψψ + H D ¯ L ⊃ g D A 0 Charge 2 Dirac Vector mass current dark Higgs Break dark U(1) with dark Higgs VEV ψ c ψ L mass = M ¯ ψψ + h H D i ¯ Dirac Majorana

Example Model Four component fermion + familiar dark photon ψγ µ ψ + M ¯ ψ c ψ µ ¯ ψψ + H D ¯ L ⊃ g D A 0 Charge 2 Dirac Vector mass current dark Higgs Break dark U(1) with dark Higgs VEV ψ c ψ L mass = M ¯ ψψ + h H D i ¯ Dirac Majorana Diagonalizing to mass basis splits Dirac components (pseudo-Dirac) ψ ≡ ( ξ , η † ) ( χ 1 , χ 2 ) , ∆ ≡ m 2 − m 1 int. eigenstates mass eigenstates

Example Model Vector current is now off-diagonal in mass basis χ 2 γ µ χ 1 + h.c. L ⊃ g D A 0 µ ¯ As before, define relic density variable e g D χ 1 χ e + ✓ m 1 ◆ 4 y ≡ ✏ 2 ↵ D m A 0 γ A 0 χ e � Different “y” for each ∆ χ 2 ✏ freeze out is subtle… direct annihilation m A 0 > m 1 + m 2

Inelastic Novelties f χ 1 Coannihilation A 0 f χ 2 χ 1 χ 2 Upscahttering & A 0 Downscattering e � e � χ 1 χ 2 Excited State Decays · e + Γ ( � 2 → � 1 e + e − ) = 4 ✏ 2 ↵↵ D ∆ 5 A 0⇤ 15 ⇡ m 4 A 0 e �

Coannihilation Relics iDM Thermal Freeze - Out 10 - 1 10 - 5 number density 10 - 9 Y = n / s Y 1 10 - 13 Y 2 Y 2 ( 0 ) Y 1 ( 0 ) 10 - 17 10 20 30 40 50 60 70 t i m e x = m 2 / T Heavier state feels Boltzmann suppression earlier Need larger rate to compensate!

Vary Mass Splitting Thermal Coannihilation, m A ' = 3 m 1 10 - 6 10 - 7 10 - 8 y = ϵ 2 α D ( m 1 / m A ' ) 4 ∆ = 0 . 4 m 1 10 - 9 10 - 10 10 - 11 ∆ = 0 . 1 m 1 10 - 12 10 - 13 10 - 14 10 - 15 10 - 16 10 2 1 10 m 1 [ MeV ]

Beam Dump Signals Detector Target/Dump χ i e/p � ! Beam e/p χ 1 χ 1 e/p χ j χ i χ 2 χ 2 A � Z and/or f + A � A � γ f � T T p π 0 , η χ 1 A � Z χ 2 Proton Electron LSND E137 BDX MiniBooNE Morrissey, Spray 1402.4817 Others possible (SeaQuest, T2K, DUNE…) Kim Park Shin 1612.06867 BdNMC deNiverville, Chen, Pospelov, Ritz 1609.01770

Missing Energy/Momentum can then decay promptly inside the detector to deposit a visible signal. ECAL/HCAL Active Target (ECAL/HCAL) Tracker Target e − e − e − − e − − χ 1 χ 2 χ 1 χ 2 → → Invisible Invisible LDMX NA64 e � χ 1 e � χ 2 A � Z Heavier state decays outside veto region Signal looks like missing energy/momentum May also be sensitive to the decay!

Generically Macroscopic Decays Rest Frame Decay Length χ 2 → χ 1 f f , y = y relic 10 9 10 8 10 7 Δ = 0.1 m 1 10 6 c τ [ y relic / y ] [ cm ] 10 5 Δ = 0.2 m 1 10 4 10 3 Δ = 0.4 m 1 10 2 10 1 10 0 10 - 1 10 - 2 10 2 10 3 10 m 2 [ MeV ]

Tiny Splitting ~ 1% Thermal iDM, Δ = 0.01 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 N eff , ( model dep. ) 10 - 7 ( g - 2 ) μ ( g - 2 ) μ 10 - 8 MiniBooNE y = ϵ 2 α D ( m 1 / m A ' ) 4 scatter BaBar mono γ 10 - 9 → 10 - 10 E137 scatter 10 - 11 Belle II 10 - 12 LSND y t i s scatter n e D c i l 10 - 13 e R BDX scatter 10 - 14 LDMX 10 - 15 missing mom. 10 - 16 10 2 10 3 1 10 m 1 [ MeV ] Similar to plots from plenaries

Small Splitting ~ 10% Thermal iDM, Δ = 0.1 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 → 10 - 7 BaBar mono γ 10 - 8 y = ϵ 2 α D ( m 1 / m A ' ) 4 E137 N eff , ( model dep. ) ( g - 2 ) μ decay 10 - 9 10 - 10 E137 scatter BDX 10 - 11 decay 10 - 12 LSND scatter LSND MiniBooNE 10 - 13 decay decay BDX scatter 10 - 14 Relic Density 10 - 15 LDMX missing mom. 10 - 16 10 2 10 3 1 10 m 1 [ MeV ] Thermal iDM, Δ = 0.3 m , m = 3 m , α = 0.1

Large Splitting ~ 40% m 1 [ MeV ] Thermal iDM, Δ = 0.4 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 N eff , ( model dep. ) BaBar 10 - 7 mono γ 10 - 8 Relic Density y = ϵ 2 α D ( m 1 / m A ' ) 4 ( g - 2 ) μ 10 - 9 E137 10 - 10 scatter E137 decay 10 - 11 LSND scatter 10 - 12 BDX decay 10 - 13 BDX 10 - 14 MiniBooNE LSND scatter decay decay 10 - 15 LDMX → missing mom. 10 - 16 10 2 10 3 1 10 m 1 [ MeV ] Target moves up, bounds/projections move down

Vary DM/Mediator Coupling Thermal iDM, Δ = 0.1 m 1 , m A' = 3 m 1 , α D = α Thermal iDM, Δ = 0.1 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 10 - 6 → → LEP 10 - 7 10 - 7 BaBar mono γ BaBar 10 - 8 10 - 8 N eff , ( model dep. ) E137 mono γ y = ϵ 2 α D ( m 1 / m A ' ) 4 y = ϵ 2 α D ( m 1 / m A ' ) 4 E137 N eff , ( model dep. ) decay ( g - 2 ) μ decay 10 - 9 10 - 9 ( g - 2 ) μ 10 - 10 10 - 10 E137 scatter Relic Density BDX E137 10 - 11 10 - 11 decay scatter BDX decay 10 - 12 LSND 10 - 12 LSND scatter scatter LSND MiniBooNE 10 - 13 10 - 13 decay decay BDX scatter LSND MiniBooNE 10 - 14 10 - 14 Relic BDX decay decay scatter Density 10 - 15 LDMX 10 - 15 LDMX missing mom. missing mom. 10 - 16 10 - 16 10 2 10 3 1 10 10 2 10 3 1 10 m 1 [ MeV ] m 1 [ MeV ] Thermal iDM, Δ = 0.3 m , m = 3 m , α = 0.1

Vary DM/Mediator Mass Ratio m 1 [ MeV ] Thermal iDM, Δ = 0.1 m 1 , m A' = 10 m 1 , α D = 0.1 Thermal iDM, Δ = 0.1 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 10 - 6 N eff , ( model dep. ) → 10 - 7 E137 10 - 7 BaBar mono γ LEP decay 10 - 8 10 - 8 y = ϵ 2 α D ( m 1 / m A ' ) 4 E137 y = ϵ 2 α D ( m 1 / m A ' ) 4 N eff , ( model dep. ) BaBar mono γ ( g - 2 ) μ decay 10 - 9 10 - 9 10 - 10 10 - 10 E137 → ( g - 2 ) μ scatter BDX BDX 10 - 11 10 - 11 decay decay y t i s n e D 10 - 12 c LSND 10 - 12 i l e R scatter E137 scatter LSND MiniBooNE 10 - 13 10 - 13 decay decay BDX LSND MiniBooNE scatter decay decay LSND scatter 10 - 14 Relic 10 - 14 Density BDX 10 - 15 LDMX 10 - 15 scatter LDMX missing mom. missing mom. 10 - 16 10 - 16 10 2 10 3 1 10 10 2 10 3 1 10 m 1 [ MeV ] m 1 [ MeV ] Thermal iDM, Δ = 0.3 m , m = 3 m , α = 0.1

Above the GeV Scale? � , ` + ` − . . . DM − c ⌧ DM ∗ ← Hadron Collider DM DM ∗ p J + 6 E T + ` + ` − p j � , ` + ` − . . . DM − c ⌧ DM ∗ ← DM Lepton Collider DM ∗ e + � + 6 E + ` + ` − e − � Izaguirre, GK, Shuve 1508.03050

Collider Complementarity Small Splitting ~ 10% Thermal iDM, Δ = 0.1 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 BaBar N eff , ( model dep. ) 10 - 7 displaced y = ϵ 2 α D ( m 1 / m A ' ) 4 10 - 8 E137 LHC ( g - 2 ) μ decay 10 - 9 displaced y t i s n e E137 D 10 - 10 c i l Belle II scatter e R mono γ 10 - 11 LSND scatter 10 - 12 BDX MiniBooNE decay decay 10 - 13 LSND BDX decay → 10 - 14 scatter LDMX 10 - 15 missing mom. 10 2 10 3 10 4 10 5 1 10 m 1 [ MeV ]

Collider Complementarity Large Splitting ~ 40% m 1 [ MeV ] Thermal iDM, Δ = 0.4 m 1 , m A ' = 3 m 1 , α D = 0.1 LEP 10 - 6 N eff , ( model dep. ) LHC 10 - 7 y = ϵ 2 α D ( m 1 / m A ' ) 4 l + l - + MET ( g - 2 ) μ 10 - 8 10 - 9 y t i s n e E137 D LHC E137 10 - 10 c BaBar i BDX l scatter e R displaced decay displaced decay 10 - 11 LSND scatter 10 - 12 BDX scatter 10 - 13 → 10 - 14 LDMX MiniBooNE missing mom. decay 10 - 15 LSND decay 10 2 10 3 10 4 10 5 1 10 m 1 [ MeV ]