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Baryogenesis and Dark Matter from B Mesons

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Baryogenesis and Dark Matter from B Mesons Baryogenesis and Dark Matter from B Mesons Miguel Escudero Abenza [email protected] Based on arXiv:1810.00880 Phys. Rev. D 99, 035031 (2019) with: Gilly Elor & Ann Nelson BLV19 24-10-2019 DARKHORIZONS The Universe Baryonic Matter 5 % 26 % Dark Matter 69 % Dark Energy Planck 2018 1807.06209 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 2 SM Prediction: Neutrinos 40 % 60 % Photons Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 3 The Universe Baryonic Matter 5 % 26 % Dark Matter 69 % Dark Energy Planck 2018 1807.06209 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 4 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables 3) Leads to unique collider signatures Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables 3) Leads to unique collider signatures 4) Fully testable at current collider experiments Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Outline 1) The Mechanism 1) C/CP violation 2) Out of equilibrium 3) Baryon number violation? 2) A Minimal Model 3) The Cosmology 4) Implications for Collider Experiments 5) Dark Matter Phenomenology 6) Summary and Outlook Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 6 Baryogenesis The three Sakharov Conditions (1967): 1) C and CP violation 2) Out of equilibrium 3) Baryon number violation Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 7 Baryogenesis from B Mesons 1) C and CP violation Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 8 Baryogenesis from B Mesons 1) C and CP violation The key quantity: the semileptonic asymmetry, Γq Γ B0 f Γ B0 f¯ Aq =Im 12 = q ! − q ! `` M q Γ B0 f + Γ B0 f¯ ✓ 12 ◆ q ! q ! Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 8 Baryogenesis from B Mesons 1) C and CP violation The key quantity: the semileptonic asymmetry, Γq Γ B0 f Γ B0 f¯ Aq =Im 12 = q ! − q ! `` M q Γ B0 f + Γ B0 f¯ ✓ 12 ◆ q ! q ! s 5 A`` SM =(2.22 0.27) 10− small because | ± ⇥ 2 Standard Model d 4 (mb/mt) is small A =( 4.7 0.6) 10− ``|SM − ± ⇥ Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 8 Baryogenesis from B Mesons 1) C and CP violation The key quantity: the semileptonic asymmetry, Γq Γ B0 f Γ B0 f¯ Aq =Im 12 = q ! − q ! `` M q Γ B0 f + Γ B0 f¯ ✓ 12 ◆ q ! q ! s 5 A`` SM =(2.22 0.27) 10− small because | ± ⇥ 2 Standard Model d 4 (mb/mt) is small A =( 4.7 0.6) 10− ``|SM − ± ⇥ s 3 A =( 0.6 2.8) 10− `` − ± ⇥ (World averages, Measurements d 3 HFLAV) A =( 2.1 1.7) 10− `` − ± ⇥ Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 8 Baryogenesis from B Mesons 1) C and CP violation The key quantity: the semileptonic asymmetry, Γq Γ B0 f Γ B0 f¯ Aq =Im 12 = q ! − q ! `` M q Γ B0 f + Γ B0 f¯ ✓ 12 ◆ q ! q ! s 5 A`` SM =(2.22 0.27) 10− small because | ± ⇥ 2 Standard Model d 4 (mb/mt) is small A =( 4.7 0.6) 10− ``|SM − ± ⇥ s 3 A =( 0.6 2.8) 10− `` − ± ⇥ (World averages, Measurements d 3 HFLAV) A =( 2.1 1.7) 10− `` − ± ⇥ • Plenty of BSM models can enlarge the asymmetries up to 10-3: SUSY, Extradim, LR, 2HDM, new generations, Leptoquarks, Z' models (see e.g. 1511.09466, 1402.1181). Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 8 Baryogenesis from B Mesons 2) Out of equilibrium and production of B Mesons Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 9 Baryogenesis from B Mesons 2) Out of equilibrium and production of B Mesons • Require the presence of an out of equilibrium particle that dominates the energy density of the Universe and reheats it to a temperature of T = (10 MeV) RH O • This particle should be very weakly coupled, with lifetimes 3 ⌧ = (10− s) Φ O • The decays don't spoil BBN or the CMB provided TRH > 5 MeV de Salas et al. 1511.00672 Hasegawa et al. 1908.10189 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 9 Baryogenesis from B Mesons 2) Out of equilibrium and production of B Mesons ¯b • Scalar particle with m Φ 11 100 GeV and 3 2 − Φ ⌧ = (10 − s) generically decays into b-quarks Φ O b b-quarks Hadronize at T<T 200 MeV • QCD ⇠ e± e± • Coherent oscillations in the B0 system are maintained in the early Universe for Temperatures: T . 20 MeV B0 B0 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 10 Baryogenesis and DM from B Mesons 3) Baryon number violation? Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 11 Baryogenesis and DM from B Mesons 3) Baryon number violation? •Baryon number is conserved in our scenario: ∆B =0 In a similar spirit to Hylogenesis, Davoudiasl, Morrissey, Sigurdson, Tulin 1008.2399 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 11 Baryogenesis and DM from B Mesons 3) Baryon number violation? •Baryon number is conserved in our scenario: ∆B =0 In a similar spirit to Hylogenesis, Davoudiasl, Morrissey, Sigurdson, Tulin 1008.2399 •We make Dark Matter an anti-Baryon and generate an asymmetry between the two sectors thanks to the CP violating oscillations and subsequents decays of B-mesons. Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 11 Baryogenesis and DM from B Mesons 3) Baryon number violation? •Baryon number is conserved in our scenario: ∆B =0 In a similar spirit to Hylogenesis, Davoudiasl, Morrissey, Sigurdson, Tulin 1008.2399 •We make Dark Matter an anti-Baryon and generate an asymmetry between the two sectors thanks to the CP violating oscillations and subsequents decays of B-mesons. Visible Sector Dark Sector (Baryons) (anti-Baryons) Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 11 Baryogenesis and DM from B Mesons 3) Baryon number violation? •Baryon number is conserved in our scenario: ∆B =0 In a similar spirit to Hylogenesis, Davoudiasl, Morrissey, Sigurdson, Tulin 1008.2399 •We make Dark Matter an anti-Baryon and generate an asymmetry between the two sectors thanks to the CP violating oscillations and subsequents decays of B-mesons. •Require a new decay mode of the B meson into DM and a visible Baryon! Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 11 A Summary of the Mechanism Out of equilibrium B-mesons decay into CP violating Oscillations late time decay Dark Matter and hadrons + 0 0 ⇠ Dark Matter ¯b B Bd Bs anti-Baryon Φ φ B ¯0 ¯0 b B− Bd Bs ⇤ Baryon d s TRH 20 MeV A A BR(B ⇠ + Baryon + ...) ⇠ `` `` ! Baryogenesis Dark Matter and 11 2 Y =8.7 10− ⌦ h =0.12 B ⇥ DM q 0 With the Baryon asymmetry: YB A Br(B ⇠+ Baryon + X) / `` ⇥ q ! qX=s,d Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 12 New B-Meson decay c c 1.2 GeV . mφ, ⇠ . 2.5 GeV y Y ⇤ ub¯ y Y ¯ s +h.c (McKeen et. al.) L ⊃−ub − s φ (anti Baryon) m > 1 TeV Dark Matter Y (4-jet/squark) ⇠ SM Singlets Y: Colored Triplet Scalar Y (3, 1, 1/3) Y ⇠ − s ¯ u b Baryon 0 ⇤ Bd d d 4 4 3 mB m 1 TeV pyuby s Br(B ⇠ + Baryon) 10− − ! ' 2 GeV m 0.53 ✓ ◆ ✓ Y ◆ Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 13 Any room for a new decay mode? Targeted decay modes are very constrained/well measured: + + 5 B-Factories Br(B K ⌫⌫¯ ) < 10− ! 0 + 9 LHC Br(B µ µ−)=(2.7 0.6) 10− s ! ± ⇥ Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 14 Any room for a new decay mode? Targeted decay modes are very constrained/well measured: + + 5 B-Factories Br(B K ⌫⌫¯ ) < 10− ! 0 + 9 LHC Br(B µ µ−)=(2.7 0.6) 10− s ! ± ⇥ But our decay mode has not been targeted! B ⇠ + Baryon ! Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 14 Any room for a new decay mode? Targeted decay modes are very constrained/well measured: + + 5 B-Factories Br(B K ⌫⌫¯ ) < 10− ! 0 + 9 LHC Br(B µ µ−)=(2.7 0.6) 10− s ! ± ⇥ But our decay mode has not been targeted! B ⇠ + Baryon ! What about the total width of B-Mesons? Measurement: Br(B+ c¯ + X) = (97 4)% ! ± Most stringent current constraint: Br(B ⇠ + Baryon + X) < 10% ! Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 14 Any room for a new decay mode? Targeted decay modes are very constrained/well measured: + + 5 B-Factories Br(B K ⌫⌫¯ ) < 10− ! 0 + 9 LHC Br(B µ µ−)=(2.7 0.6) 10− s ! ± ⇥ But our decay mode has not been targeted! B ⇠ + Baryon ! What about the total width of B-Mesons? Measurement: Br(B+ c¯ + X) = (97 4)% ! ± Most stringent current constraint: Br(B ⇠ + Baryon + X) < 10% ! Ongoing searches with Belle-II data Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 14 The Boltzmann Equations 1 da 2 8⇡ Universe's Evolution H2 = (⇢ + m n ) ⌘ a dt 3m2 rad Φ Φ ✓ ◆ Pl dnΦ Late time Decay +3HnΦ = ΓΦnΦ and dt − d⇢ Radiation rad +4H⇢ = Γ m n dt rad Φ Φ Φ dn⇠ 2 2 B B +3Hn = σv (n n )+2Γ n ΓΦ ΓΦ Br(B ⇠ + Baryon + X) dt ⇠ h i⇠ ⇠ − eq,⇠ Φ Φ ⌘ ⇥ ! dnφ B q 0 q DM evolution +3Hn = σv (n n ? n n ? )+Γ n [1 + A Br(¯b B ) f ] dt φ h iφ φ φ − eq,φ eq,φ Φ Φ ⇥ `` ! q deco q X dnφ? B q 0 q +3Hn ? = σv (n n ? n n ? )+Γ n [1 A Br(¯b B ) f ] dt φ h iφ φ φ − eq,φ eq,φ Φ Φ ⇥ − `` ! q deco q X dn Baryon asymmetry: B +3Hn =2Γ n Br(¯b B0) f q Aq Br(B ⇠ + Baryon + X) dt B Φ Φ ! q deco `` ! n = n n ? q B φ − φ X • Baryon asymmetry directly related to the CP violation in the B0 system and to the new decay of B mesons to a visible Baryon and missing energy.
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