Lepton non-universality at LEP and charged Higgs

Transcription

1 Lepton non-universality at LEP and charged Higgs Jae-hyeon Park TU Dresden Institutsseminar TU Dresden,

2 Standard Model L SM = 1 4 F F+ ψi/dψ [H ψ L Y ψ R+ h.c.] + g2 θ 32π 2 F F+ DH 2 V(H) Omitted: Majorana mass terms of neutrinos Lepton non-universality at LEP and charged Higgs TUD / / 22

3 Standard Model L SM = 1 4 F F + ψi/dψ [H ψ L Y ψ R + h.c.] + g2 θ 32π 2 F F+ DH 2 V(H) tested Omitted: Majorana mass terms of neutrinos Lepton non-universality at LEP and charged Higgs TUD / / 22

4 Standard Model L SM = 1 4 F F + ψi/dψ [H ψ L Y ψ R + h.c.] + g2 θ 32π 2 F F+ D H 2 V(H) tested probed Omitted: Majorana mass terms of neutrinos Lepton non-universality at LEP and charged Higgs TUD / / 22

5 Standard Model L SM = 1 4 F F + ψi/dψ [H ψ L Y ψ R + h.c.] + g2 θ 32π 2 F F+ D H 2 V(H) tested probed constrained Omitted: Majorana mass terms of neutrinos Lepton non-universality at LEP and charged Higgs TUD / / 22

6 Standard Model L SM = 1 4 F F + ψi/dψ [H ψ L Y ψ R + h.c.] + g2 θ 32π 2 F F+ D H 2 V(H) tested constrained probed to be explored Omitted: Majorana mass terms of neutrinos Lepton non-universality at LEP and charged Higgs TUD / / 22

7 Lepton universality in charged current interactions SM predicts lepton universality. W boson couplings to e, µ,τ are determined by SU(2) gauge invariance. L CC = g ( ) 2 W µ ν l γ µ 1 γ5 l+h.c. 2 l=e,µ,τ Thoroughly tested in µ eνν, τ µνν, τ eνν, π eν, π µν, τ πν,... All these consistent with lepton universality. Lepton non-universality at LEP and charged Higgs TUD / / 22

8 Test of lepton universality at µ eνν and τ µνν Use parameterization L CC = l=e,µ,τ Take ratio Γ(τ µνν)/γ(µ eνν): τ µ g τ W g µ W g µ g e ν τ ν µ µ ν µ e ν e ( ) g l W µ ν l γ µ 1 γ5 l+h.c (g τ /g e ) τµ = ± Data from Loinaz, Okamura, Rayyan, Takeuchi, Wijewardhana, PRD(2004) Lepton non-universality at LEP and charged Higgs TUD / / 22

9 Test of lepton universality at µ eνν and τ µνν Use parameterization L CC = l=e,µ,τ Take ratio Γ(τ µνν)/γ(µ eνν): τ µ g τ W g µ W g µ g e ν τ ν µ µ ν µ e ν e ( ) g l W µ ν l γ µ 1 γ5 l+h.c (g τ /g e ) τµ = ± Perfect agreement with lepton universality Data from Loinaz, Okamura, Rayyan, Takeuchi, Wijewardhana, PRD(2004) Lepton non-universality at LEP and charged Higgs TUD / / 22

10 Measurement of B(W lν) at LEP LEP directly measured B(W eν e ), B(W µν µ ), B(W τν τ ), from partial cross sections of WW 4f. e e + ν e W f 1 f 1 e W f 2 f 2 f 3 γ,z f 3 W + e + W + f 4 f 4 (f 1,f 2 )=(e,ν e ),(µ,ν µ ),(τ,ν τ ),(d,u),(s,c). (f 4,f 3 ) is a conjugate. Lepton non-universality at LEP and charged Higgs TUD / / 22

11 Tau mode excess LEP electroweak working group, hep-ex/ LEP results Experiment B(W eν e ) [%] B(W µν µ ) [%] B(W τν τ ) [%] ALEPH 10.78± ± ±0.38 DELPHI 10.55± ± ±0.43 L ± ± ±0.45 OPAL ± ± ± 0.48 LEP ± ± ± 0.22 Under assumption of B(W eν e )=B(W µν µ ), B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = 1.077±0.026 LEP New physics? Lepton non-universality at LEP and charged Higgs TUD / / 22

12 Tau mode excess LEP electroweak working group, hep-ex/ LEP results Experiment B(W eν e ) [%] B(W µν µ ) [%] B(W τν τ ) [%] ALEPH 10.78± ± ±0.38 DELPHI 10.55± ± ±0.43 L ± ± ±0.45 OPAL ± ± ± 0.48 LEP ± ± ± 0.22 Under assumption of B(W eν e )=B(W µν µ ), B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = 1.077±0.026 LEP New physics? Lepton non-universality at LEP and charged Higgs TUD / / 22

13 Tau mode excess LEP electroweak working group, hep-ex/ LEP results Experiment B(W eν e ) [%] B(W µν µ ) [%] B(W τν τ ) [%] ALEPH 10.78± ± ±0.38 DELPHI 10.55± ± ±0.43 L ± ± ±0.45 OPAL ± ± ± 0.48 LEP ± ± ± 0.22 Under assumption of B(W eν e )=B(W µν µ ), B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = 1.077±0.026 LEP 7.7% or 2.8 σ departure from lepton universality. New physics? Lepton non-universality at LEP and charged Higgs TUD / / 22

14 Previous attempts for explanation X.-Y. Li, E. Ma, hep-ph/ Gauge model of generation non-universality. Two SU(2) gauge groups: one for 1st and 2nd family fermions, the other for 3rd. Mixing of gauge bosons leads to flavor-dependent lightest W boson couplings to leptons. Can fit leptonic W branching ratios. Lepton non-universality at LEP and charged Higgs TUD / / 22

15 Previous attempts for explanation X.-Y. Li, E. Ma, hep-ph/ Gauge model of generation non-universality. Two SU(2) gauge groups: one for 1st and 2nd family fermions, the other for 3rd. Mixing of gauge bosons leads to flavor-dependent lightest W boson couplings to leptons. Can fit leptonic W branching ratios. However, it decreases Γ(τ µνν)/γ(µ eνν) by 7% 15 σ ruled out. Lepton non-universality at LEP and charged Higgs TUD / / 22

16 Dilemma A model leading to effective interactions L CC = l=e,µ,τ g l ( W µ ν l γ µ 1 γ5 2 2 ) l+h.c., with g τ g e,µ, generically conflicts with lepton universality tests from µ, τ decays. A different approach is preferable. Lepton non-universality at LEP and charged Higgs TUD / / 22

17 Dilemma A model leading to effective interactions L CC = l=e,µ,τ g l ( W µ ν l γ µ 1 γ5 2 2 ) l+h.c., with g τ g e,µ, generically conflicts with lepton universality tests from µ, τ decays. W τ ν τ A different approach is preferable. Lepton non-universality at LEP and charged Higgs TUD / / 22

18 Dilemma A model leading to effective interactions L CC = l=e,µ,τ g l ( W µ ν l γ µ 1 γ5 2 2 ) l+h.c., with g τ g e,µ, generically conflicts with lepton universality tests from µ, τ decays. ν τ τ τ W µ W ν τ µ W ν µ ν µ e ν e A different approach is preferable. Lepton non-universality at LEP and charged Higgs TUD / / 22

19 Dilemma A model leading to effective interactions L CC = l=e,µ,τ g l ( W µ ν l γ µ 1 γ5 2 2 ) l+h.c., with g τ g e,µ, generically conflicts with lepton universality tests from µ, τ decays. ν τ τ τ W µ W ν τ µ W ν µ ν µ e ν e A different approach is preferable. Lepton non-universality at LEP and charged Higgs TUD / / 22

20 Outline 1 Introduction 2 Charged Higgs solution 3 Constraints from data 4 Effects on B(W lν) 5 Test at future experiments 6 Other related works Lepton non-universality at LEP and charged Higgs TUD / / 22

21 Can charged Higgs be a solution? JhP, JHEP(2006) Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 e W f 2 f 2 f 3 γ,z f 3 W + e + W + f 4 f 4 B(W lν) is measured by counting final state fermions. σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

22 Can charged Higgs be a solution? JhP, JHEP(2006) Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 f 1 e W e H f 2 f 2 f 2 f 3 γ,z f 3 γ,z f 3 W + e + W + e + H + f 4 f 4 f 4 B(W lν) is measured by counting final state fermions. σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

23 Can charged Higgs be a solution? JhP, JHEP(2006) Suppose H + H pairs were produced at LEP. e ν e e + W f 1 f 1 f 1 e W e H f 2 f 2 f 2 f 3 γ,z f 3 γ,z f 3 W + e + W + e + H + f 4 f 4 f 4 Mostly, (f 1,f 2 )=(τ,ν τ ),(s,c). B(W lν) is measured by counting final state fermions. σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

24 Can charged Higgs be a solution? Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 f 1 e W e H f 2 f 2 f 2 W + f 3 f 4 e + γ,z B(W lν) is measured by counting final state fermions. W + f 3 f 4 e + γ,z H + JhP, JHEP(2006) f 3 f 4 Mostly, (f 1,f 2 )=(τ,ν τ ),(s,c). Charged Higgs contamination may appear as excessive B(W τν τ ) σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

25 Can charged Higgs be a solution? Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 f 1 e W e H f 2 f 2 f 2 W + f 3 f 4 e + γ,z B(W lν) is measured by counting final state fermions. W + f 3 f 4 e + γ,z H + JhP, JHEP(2006) f 3 f 4 Mostly, (f 1,f 2 )=(τ,ν τ ),(s,c). Charged Higgs contamination may appear as excessive B(W τν τ ) σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

26 Can charged Higgs be a solution? Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 f 1 e W e H f 2 f 2 f 2 W + f 3 f 4 e + γ,z B(W lν) is measured by counting final state fermions. W + f 3 f 4 e + γ,z H + JhP, JHEP(2006) f 3 f 4 Mostly, (f 1,f 2 )=(τ,ν τ ),(s,c). Charged Higgs contamination may appear as excessive B(W τν τ ) σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

27 Can charged Higgs be a solution? Suppose H + H pairs were produced at LEP. e e + ν e W f 1 f 1 f 1 e W e H f 2 f 2 f 2 W + f 3 f 4 e + γ,z B(W lν) is measured by counting final state fermions. W + f 3 f 4 e + γ,z H + JhP, JHEP(2006) f 3 f 4 Mostly, (f 1,f 2 )=(τ,ν τ ),(s,c). Charged Higgs contamination may appear as excessive B(W τν τ ) σ HH is a decreasing function of m H ± m H ± m W desirable. See the plot on Page 17. Hard (but not impossible) to realize in MSSM due to m 2 H ± = m 2 W + m2 A and m A > 93 GeV. Here consider a 2HDM. Lepton non-universality at LEP and charged Higgs TUD / / 22

28 2HDM s free of tree-level FCNC Make assumptions on Higgs Yukawa couplings for suppressing tree-level FCNC. Four example models Model labels borrowed from Barger, Hewett, Phillips, PRD(1990) Models I II III IV ( u d ( ν l ) ) VEV A f VEV A f VEV A f VEV A f H 2 cotβ H 2 cotβ H 2 cotβ H 2 cotβ H 2 cotβ H 1 tanβ H 1 tanβ H 2 cotβ H 2 cotβ H 1 tanβ H 2 cotβ H 1 tanβ tanβ v 2 /v 1 H ± -fermion-fermion interaction Lagrangian L = g 2mW H + [V ij m ui A u u Ri d Lj + V ij m dj A d u Li d Rj + m l A l ν L l R ]+h.c. governs b sγ, H ± τν τ,... Lepton non-universality at LEP and charged Higgs TUD / / 22

29 2HDM s free of tree-level FCNC Make assumptions on Higgs Yukawa couplings for suppressing tree-level FCNC. Four example models Model labels borrowed from Barger, Hewett, Phillips, PRD(1990) Models I II III IV ( u d ( ν l ) ) VEV A f VEV A f VEV A f VEV A f H 2 cotβ H 2 cotβ H 2 cotβ H 2 cotβ H 2 cotβ H 1 tanβ H 1 tanβ H 2 cotβ H 2 cotβ H 1 tanβ H 2 cotβ H 1 tanβ tanβ v 2 /v 1 H ± -fermion-fermion interaction Lagrangian L = g H + [V ij m ui A u u Ri d Lj + V ij m dj A d u Li d Rj + m l A l ν L l R ]+h.c. 2mW governs b sγ, H ± τν τ,... H + in Model I becomes fermiophobic for high tanβ Lepton non-universality at LEP and charged Higgs TUD / / 22

30 b sγ constraint One of the most stringent constraints on m H ±. Branching ratio in 2HDM: B(B X s γ) B SM (B X s γ) = C SM 7γ (m b)+c H± C SM 7γ (m b) 7γ (m 2 b) = A u A d A 2 u 2 In Models II and III, A u A d = 1, and therefore excluded. B(B X s γ) B SM (B X s γ) 2.9 for m H ± m W In Models I and IV, A u = A d = cotβ, Lepton non-universality at LEP and charged Higgs TUD / / 22

31 b sγ constraint One of the most stringent constraints on m H ±. Branching ratio in 2HDM: B(B X s γ) B SM (B X s γ) = C SM 7γ (m b)+c H± C SM 7γ (m b) 7γ (m 2 b) = A u A d A 2 u 2 In Models II and III, A u A d = 1, and therefore excluded. B(B X s γ) B SM (B X s γ) 2.9 for m H ± m W In Models I and IV, A u = A d = cotβ, Lepton non-universality at LEP and charged Higgs TUD / / 22

32 b sγ constraint One of the most stringent constraints on m H ±. Branching ratio in 2HDM: B(B X s γ) B SM (B X s γ) = C SM 7γ (m b)+c H± C SM 7γ (m b) 7γ (m 2 b) = A u A d A 2 u 2 In Models II and III, A u A d = 1, and therefore excluded. B(B X s γ) B SM (B X s γ) 2.9 for m H ± m W In Models I and IV, A u = A d = cotβ, Models I and IV survive if tanβ 4 Lepton non-universality at LEP and charged Higgs TUD / / 22

33 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : 1.0 B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. b sγ and direct search largely determine one viable model. Consider only Model I from here on. Lepton non-universality at LEP and charged Higgs TUD / / 22

34 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : 1.0 B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. ALEPH, PLB(2002) b sγ and direct search largely determine one viable model. Consider only Model I from here on. Lepton non-universality at LEP and charged Higgs TUD / / 22

35 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : 1.0 B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. ALEPH, PLB(2002) b sγ and direct search largely determine one viable model. Consider only Model I from here on. Lepton non-universality at LEP and charged Higgs TUD / / 22

36 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : 1.0 B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β ALEPH, PLB(2002) Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. Model I is favored for m H ± m W b sγ and direct search largely determine one viable model. Consider only Model I from here on. Lepton non-universality at LEP and charged Higgs TUD / / 22

37 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : 1.0 B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β ALEPH, PLB(2002) Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. Model I is favored for m H ± m W b sγ and direct search largely determine one viable model. Consider only Model I from here on. Lepton non-universality at LEP and charged Higgs TUD / / 22

38 Direct constraints on m H ± B(H ± τν τ ) as a function of tanβ : B H ± ΤΝ LEP excluded Models II, IV Model III Model I tan Β BR(H ± τν) OPAL: H + H -, BR(H ± τν)+br(h ± qq)= excluded 95% CL, observed 95% CL, expected 90% CL, observed 99% CL, observed m ± H (GeV) Hatched region is excluded for m H ± = 86 GeV [plot on Page 17]. Model IV leads to B(H ± τν τ ) 0.99 for tanβ 4. Model I is favored for m H ± m W b sγ and direct search largely determine one viable model. Consider only Model I from here on. OPAL, Lepton non-universality at LEP and charged Higgs TUD / / 22

39 Other constraints From LEP W-pair production cross section: σhh < 1% σ WW < error of σ WW Angular distribution of W-pair: measured from qqeν and qqµν final states irrelevant. Anomalous triple-gauge-boson couplings measurement: charged Higgs effect is smaller than or comparable to an error. W mass and width: shifts are smaller than errors. S, T, and U: okay unless neutral Higgses are too heavy. From CDF t H + b: constraint weakens as tanβ grows safe for tanβ 1. FCNC and CP violation: B s B s, B 0 B 0, K 0 K 0, ε /ε K, B τν,... H ± decouples from fermions for high tanβ Safe for tanβ 4. Lepton non-universality at LEP and charged Higgs TUD / / 22

40 Other constraints From LEP W-pair production cross section: σhh < 1% σ WW < error of σ WW Angular distribution of W-pair: measured from qqeν and qqµν final states irrelevant. Anomalous triple-gauge-boson couplings measurement: charged Higgs effect is smaller than or comparable to an error. W mass and width: shifts are smaller than errors. S, T, and U: okay unless neutral Higgses are too heavy. From CDF t H + b: constraint weakens as tanβ grows safe for tanβ 1. FCNC and CP violation: B s B s, B 0 B 0, K 0 K 0, ε /ε K, B τν,... H ± decouples from fermions for high tanβ Safe for tanβ 4. Lepton non-universality at LEP and charged Higgs TUD / / 22

41 Other constraints From LEP W-pair production cross section: σhh < 1% σ WW < error of σ WW Angular distribution of W-pair: measured from qqeν and qqµν final states irrelevant. Anomalous triple-gauge-boson couplings measurement: charged Higgs effect is smaller than or comparable to an error. W mass and width: shifts are smaller than errors. S, T, and U: okay unless neutral Higgses are too heavy. From CDF t H + b: constraint weakens as tanβ grows safe for tanβ 1. FCNC and CP violation: B s B s, B 0 B 0, K 0 K 0, ε /ε K, B τν,... H ± decouples from fermions for high tanβ Safe for tanβ 4. For the same reason, Γ(τ µνν)/γ(µ eνν) [µ, τ, π, K decays] safe if tanβ 0.03 A feature not shared by non-universal charged current interaction models! Lepton non-universality at LEP and charged Higgs TUD / / 22

42 Other constraints From LEP W-pair production cross section: σhh < 1% σ WW < error of σ WW Angular distribution of W-pair: measured from qqeν and qqµν final states irrelevant. Anomalous triple-gauge-boson couplings measurement: charged Higgs effect is smaller than or comparable to an error. W mass and width: shifts are smaller than errors. S, T, and U: okay unless neutral Higgses are too heavy. From CDF t H + b: constraint weakens as tanβ grows safe for tanβ 1. FCNC and CP violation: B s B s, B 0 B 0, K 0 K 0, ε /ε K, B τν,... H ± decouples from fermions for high tanβ Safe for tanβ 4. For the same reason, Γ(τ µνν)/γ(µ eνν) [µ, τ, π, K decays] safe if tanβ 0.03 A feature not shared by non-universal charged current interaction models! Okay thanks to H + s fermiophobia for high tanβ Lepton non-universality at LEP and charged Higgs TUD / / 22

43 How effective is charged Higgs contribution? Take m H ± = 81 GeV, s=200 GeV σ HH = 0.14 pb,σ WW = 17 pb For Model I, B(H ± qq)=0.3 and B(H ± τν τ )=0.7 B(W qq)=6/9, B(W µν µ )=1/9 Estimate using qqτν and qqµν modes: B(W τν τ ) B(W µν µ ) = σ qqτν WW + σ qqτν HH appar Estimate using τντν and µνµν: B(W τν τ ) B(W µν µ ) = appar σ qqµν WW = 1+ σ HH B(H ± τν τ ) σ WW B(W µν µ ) 1+ σ HH σ WW B(H ± qq) B(W qq) 1.02 ( B(H ± ) 2 τν τ ) 1.15 B(W µν µ ) Can accommodate a few % of tau mode excess. Lepton non-universality at LEP and charged Higgs TUD / / 22

44 How effective is charged Higgs contribution? Take m H ± = 81 GeV, s=200 GeV σ HH = 0.14 pb,σ WW = 17 pb For Model I, B(H ± qq)=0.3 and B(H ± τν τ )=0.7 B(W qq)=6/9, B(W µν µ )=1/9 Estimate using qqτν and qqµν modes: B(W τν τ ) B(W µν µ ) = σ qqτν WW + σ qqτν HH appar Estimate using τντν and µνµν: B(W τν τ ) B(W µν µ ) = appar σ qqµν WW = 1+ σ HH B(H ± τν τ ) σ WW B(W µν µ ) 1+ σ HH σ WW B(H ± qq) B(W qq) 1.02 ( B(H ± ) 2 τν τ ) 1.15 B(W µν µ ) Can accommodate a few % of tau mode excess. Lepton non-universality at LEP and charged Higgs TUD / / 22

45 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality at LEP and charged Higgs TUD / / 22

46 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality at LEP and charged Higgs TUD / / 22

47 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality at LEP and charged Higgs TUD / / 22

48 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality at LEP and charged Higgs TUD / / 22

49 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality at LEP and charged Higgs TUD / / 22

50 Maximum likelihood fit Use data available in DELPHI, EPJC (2004). Likelihood fit with only W gives B(W τν τ ) [B(W eν e )+ B(W µν µ )]/2 = W only Likelihood fit in 2HDM I gives B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 = HDM fit for m H ± = 81 GeV. Tau mode excess diminished by 4%. Can expect an improvement of the ratio B(W τν τ ) [B(W eν e )+B(W µν µ )]/ ± LEP,2HDM Lepton non-universality reduced to 1.4 σ Lepton non-universality at LEP and charged Higgs TUD / / 22

51 Charged Higgs mass dependence of the fit Likelihood fit result of r as a function of m H ±: B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 2HDM fit r Σ W only m H ± GeV The lighter, the better, but for Model I, LEP constrains m H ± > 80.7 GeV. Lepton non-universality at LEP and charged Higgs TUD / / 22

52 Charged Higgs mass dependence of the fit Likelihood fit result of r as a function of m H ±: B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 2HDM fit r Σ W only m H ± GeV 1-σ mitigation needs m H ± 86 GeV The lighter, the better, but for Model I, LEP constrains m H ± > 80.7 GeV. Lepton non-universality at LEP and charged Higgs TUD / / 22

53 Charged Higgs mass dependence of the fit Likelihood fit result of r as a function of m H ±: B(W τν τ ) [B(W eν e )+B(W µν µ )]/2 2HDM fit r Σ W only m H ± GeV 1-σ mitigation needs m H ± 86 GeV The lighter, the better, but for Model I, LEP constrains m H ± > 80.7 GeV. Lepton non-universality at LEP and charged Higgs TUD / / 22

54 Test at ILC What to look for: charged Higgs with m H ± m W that couples very weakly to fermions. Test of scenario is charged Higgs search. Doable at ILC. Beam polarization helps a lot. e /e + polarization σ HH [pb] σ WW [pb] σ HH /σ WW [%] 0%/ 0% %/ 0% %/ 0% %/60% %/60% for s=500 GeV, right-handed electron and left-handed positron beam polarizations. At LHC? Lepton non-universality at LEP and charged Higgs TUD / / 22

55 Test at ILC What to look for: charged Higgs with m H ± m W that couples very weakly to fermions. Test of scenario is charged Higgs search. Doable at ILC. Beam polarization helps a lot. e /e + polarization σ HH [pb] σ WW [pb] σ HH /σ WW [%] 0%/ 0% %/ 0% %/ 0% %/60% %/60% for s=500 GeV, right-handed electron and left-handed positron beam polarizations. At LHC? Lepton non-universality at LEP and charged Higgs TUD / / 22

56 Test at ILC What to look for: charged Higgs with m H ± m W that couples very weakly to fermions. Test of scenario is charged Higgs search. Doable at ILC. Beam polarization helps a lot. e /e + polarization σ HH [pb] σ WW [pb] σ HH /σ WW [%] 0%/ 0% %/ 0% %/ 0% %/60% %/60% for s=500 GeV, right-handed electron and left-handed positron beam polarizations. At LHC? Lepton non-universality at LEP and charged Higgs TUD / / 22

57 Test at ILC What to look for: charged Higgs with m H ± m W that couples very weakly to fermions. Test of scenario is charged Higgs search. Doable at ILC. Beam polarization helps a lot. e /e + polarization σ HH [pb] σ WW [pb] σ HH /σ WW [%] 0%/ 0% %/ 0% %/ 0% %/60% %/60% for s=500 GeV, right-handed electron and left-handed positron beam polarizations. At LHC? What do you think? Lepton non-universality at LEP and charged Higgs TUD / / 22

58 Summary A resolution is proposed of the possible lepton non-universality observed at the W-pair production experiments at LEP. H ± almost degenerate with W, within 2HDM, could reduce 2.8 σ of deviation down to 1.4 σ. No conflict with the existing direct or indirect constraints. In particular, µ, τ, π, K decays are safe. Charged Higgs direct search at LEP in combination with b sγ singles out one viable type of 2HDM out of the four that are free of tree-level FCNC interactions. No tan β dependence in prediction. Testable at ILC. Lepton non-universality at LEP and charged Higgs TUD / / 22

59 A supersymmetric solution Light CP-odd Higgs scenario where m A < 2m b. m H ± = m 2 W + m2 A m W Dermisek, Circumvent LEP bound, m A > 93 GeV, by suppressing σ(e + e ha) cos 2 (β α). Escape from detection of higgstrahlung, e + e hz, using B(h AA,b b) 90%,10%, plus A τ + τ,c c, and/or adding a singlet to MSSM. As for b sγ, cancel charged Higgs loop with chargino-stop loop. Account for apparent excess of B(W τν τ ) at LEP using H ± τν τ. Dermisek, Lepton non-universality at LEP and charged Higgs TUD / / 22

60 More plots W-pair production cross section Σ WW Σ pb Σ HH Error of σ WW is between 0.21 pb and 0.7 pb s GeV S, T, U constraints Constraints on m h and m A from δt, with m H /m h fixed at 1.0, 1.5, and 2.0, respectively. S and U constraints are weaker. ma GeV allowed by T m H m h m h GeV Lepton non-universality at LEP and charged Higgs TUD / / 22

61 Fit in 2HDM Modify channel cross sections as σ qqτν s = σ WW,s 2B(W qq)b(w τν τ )+σ HH,s 2B(H ± qq)b(h ± τν τ ) σ τντν s = σ WW,s B 2 (W τν τ )+σ HH,s B 2 (H ± τν τ ) σ qqqq s = σ WW,s B 2 (W qq)+σ HH,s B 2 (H ± qq) Use B(H ± qq)=0.3 and B(H ± τν τ )=0.7 for Model I, and calculated σ HH,s. Fit variables are B(W eν e ),B(W µν µ ),B(W τν τ ),σ WW,s. Lepton non-universality at LEP and charged Higgs TUD / / 22