660 likes | 786 Vues
v. S.L. Olsen U of Hawai’i 高能所 北京. B-factory constraints on possible New Physics at the LHC. Academia Sinica (Taipei) June 12, 2007. Outline. Implications of recent D 0 -D 0 mixing results CPV measurements with Penguins Charged Higgs limits Light dark matter searches.
E N D
v S.L. Olsen U of Hawai’i 高能所 北京 B-factory constraints on possibleNew Physicsat the LHC Academia Sinica (Taipei) June 12, 2007
Outline • Implications of recent D0-D0 mixing results • CPV measurements with Penguins • Charged Higgs limits • Light dark matter searches
SUSY “Flavor Problem” K0-K0 mixing SM: NP (MSSM): QCD-vertices EW-vertices 6x6 matrix 2nd order EW: Δm 3 x 10-12 MeV Potentially huge: effects not seen
How to make Δm small? PLB 309, 337 (1993)
Quark-Squark “Alignment” Invoke a horizontal symmetry that results in small values for the down-type squark mixing This fixes up-type squark mixing elements cosqC (~0.2) Expect large effects in D0-D0 mixing e.g. Δm ~ 6x10-11 MeV Nir & Raz PRD 66, 035007 (2002)
Neutral D meson phenomenology SM: CPV is very small: q ≈ p ≈1/2
Recent D0-D0 mixing results (I) “Wrong sign” (WS) decays D*+ p+ D0 D0 K+p- pion charge tags the D0 flavor DCS decays
mixing evidence from WS decays BaBar excludes no-mixing at 3.9s strong phase
Recent D0-D0 mixing results (II) D2-D1 lifetime diff: Kp Kp D0 = (1/2) (D1 + D2) x KK,pp KK,pp Lifetime measured w D0Kp decays = <t1 + t2>/2 “ “ w D0KK & pp decays = t1
Belle measurement of ycp hep-ex/0703036 accepted by PRL For CPV = 0: yCP = y
Recent D0-D0 mixing results III Dalitz analysis of D0KSp+p- decays D*+ p+ D0 D0 t-dependent interference KSp+p- pion charge tags D0 flavor @ t=0 D0 decay D0 decay
Dalitz analysis of D0KSp+p- D0K*-p+ K*+/K*- + D0K*+p-
95% CL contour Results HFAG YCP (0,0) excluded at 2.7s level x = (0.80 0.29 0.17) % y = (0.33 0.24 0.15)% = (410.3 0.3) fs
Commentsalà Y. Nir hep-ph/0703235v2 • D0-D0 mixing probably observed in ΔΓ • y = (Γ1-Γ2)/2Γ = (1.4 ± 0.4) x 10-2 • Mass difference still not seen • x < 0.015 @ 95% CL • Δm < 1.2 x 10-11 MeV (CP conserved) • Δm < 2.2 x 10-11 MeV (CP violated) • ~factor of 3 below m≈1TeV q/g expectation ~ ~ ~ ~ ~
Making ΔM small in the MSSM • fine-tune the squark mixing terms • SUSY is supposed to save us from fine-tuning • make the squark masses degenerate GIM • unlike ordinary quarks: mt/mu ~ 105 • raise the SUSY mass scale ( ~few TeV) • not much fun for LHC experimenters
CPV in the SM complex terms in the CKM quark-flavor mixing matrix Wolfenstein bu (f3) td (f1)
sin21from BfCP + BBfCPinterf. J/y Vcb B0 KS V*2 sin2f1 no CP phase td J/y V* Vtb td B0 B0 KS Vtb V* td Sanda, Bigi & Carter:
What do we measure? Flavor-tag decay (B0 or B0 ?) Asymmetric energies J/ e fCP e t=0 KS z B - B B + B sin21 more B tags t z/cβγ (tags) more B tags This is for CP=-1; for CP=+1, the asymmetry is opposite
Results (2006) Belle BaBar
sin2f1(b) history LP2001 Rome
CKM with (mostly) trees CKM Global Fit (Sep.2006) SM+CKM is “correct” at tree level
Next Step Check the Unitary Triangle with Penguins bs FCNC decay
SM FCNC: NP: QCD-vertices EW-vertices ~ ~ c- g ~ ~ ~ c ~ s t b x t x 2nd-order Weak process 2nd-order QCD process huge effects are possible (but not seen) This mixing matrix is 6x6 (lots of CP phases) at least V i.e. > 0.1 for MNP accessible @ LHC
sin2f1 with bs penguins (SM) Example: no CP phase f1 * Vtd , h’, K+K- , h’, K+K- + B B * Vtd f1 SM: sin2f1 =sin2f1 from BJ/y KS (bc c s) _ eff
hep-ex/0608039 B0h'K0 K0KS K0KL B0 momentum B0 mass (bkg subtracted) h’ rg Ks(p+p-) 794 36 h(2g)pp Ks(p+p-) 363 21 h(3p)pp Ks(p+p-) 100 11 rg Ks(p0p0) 103 15 h(2g)pp Ks(p0p0) 62 9 Total1421 46 h’h(2g)pp KL 392 37 h(3p)pp KL 62 13 Total 454 39
hep-ex/0608039 TCPV in B0h'K0 “sin2f1” = +0.64 0.10(stat) 0.04(syst) A = -0.01 0.07(stat) 0.05(syst) Dt distribution and asymmetry • Consistent with the SM • Consistent with Belle 2005 (Belle 2005: “sin2f1” = +0.620.120.04) • First observation of TCPV • (5.6s) in a single bgs mode • h'KS and h'KL combined • background subtracted • good tags • Dt g –Dt for h'KL
hep-ex/0608039 B0 fK0 fgK+K-, KSgp+p- fgK+K-, KSgp0p0 fgKSKL, KSgp+p- 24618 409 227 30721 fKS signal fgK+K- 11417 fKLsignal K0KL K0KS (bkg subtracted) B0 momentum B0 mass
hep-ex/0608039 TCPV in B0gfK0 Preliminary “sin2f1” = +0.50 0.21(stat) 0.06(syst) A = +0.07 0.15(stat) 0.05(syst) Dt distribution and asymmetry • Consistent with the SM (~1s lower) • Consistent with Belle 2005 (Belle2005: “sin2f1” = +0.440.270.05) • fKS and fKL combined • background subtracted • good tags • Dt g –Dt for fKL unbinned fit SM
Smaller than bgccs in all of 9 modes Theory tends to predict positive shifts (originating from phase in Vts) 2006: f1 with bgs Penguins Naïve average of all b g s modes sin2beff = 0.52 ± 0.05 2.6 s deviation between penguin and tree (b g s) (b g c)
eff History of sin2f1 2.8s 2.6s 2.6s 3.1s 3.9s sin2f1 from bccs decays (2007) D 0.15 sin2f1 (bqqs decays) (Belle&BaBar average) 2002 2003 2004 2005 2006
How to make Δsin2f1 small? eff ~ g ~ ~ s b x • Tune the squark mixing terms • is there enough freedom to do this? • Make the squark masses degenerate • invoke a GIM-like mechanism • Make the SUSY mass scale very high (~few TeV) • not much fun for LHC experimenters
B Decays w/ “Missing E(>1n)” SM : B decay constant Lattice QCD BSM : sensitive to New Physics from H
449M BB B tn(nearly invisible decays) tn signal B e- (8GeV) e+(3.5GeV) Υ(4S) p B Tag-side: Full reconstruction N= 680k eff.= 0.29% purity = 57% 4-momentum determined B meson beam ! Charged B
B candidate event Missing momentum
B tn results Belle Hadronic tags PRL97, 251802 (2006). e+nn (3.6%) m+nn (2.4%) p+n (4.9%)p+p0n(2.0%) pppn (0.8%) First evidence, 3.5 s
BaBar results on Btn Gritsan@FPCP07 D l n tags hep-ex/0608019 hadron tags BaBar combined result:
Belle measures: Branching fraction Babar preliminary Product of B meson decay constant ƒB and CKM element |Vub | Compare with
Constraints on H mass Use known fB and |Vub |Ratio to the SM BF. excluded rH=1.130.51 excluded
Radiative Penguins b sl +l - b sg
New Physics? b sg b sl +l - H- ~ t ~ t ~ c- ~ c-
NNLO theory Theory News M. Misiak et al, hep-ph/0609232, PRL 98,022002(2007) NNLO calculation (29826) x 10-6