Low Energy Precision Tests of Supersymmetry

Transcription

1 Low Energy Precision Tests of Supersymmetry M.J. Ramsey-Musolf Caltech Wisconsin-Madison M.R-M & S. Su, hep-ph/ J. Erler & M.R-M, PPNP 54, 351 (2005)

2 Outline I. Motivation: Why New Symmetries? Why Low Energy Probes? II. Prime Suspect: Supersymmetry III. Low Energy Precision Tests Weak Decays PVES

3 I. Motivation Why New Symmetries? Why Low Energy Probes?

4 Fundamental Symmetries & Cosmic History Electroweak symmetry Puzzles the breaking: Standard Higgs Model? can t solve 1. Origin of matter 2. Unification & gravity 3. Weak scale stability 4. Neutrinos What are the symmetries (forces) of the early universe beyond those of the SM? Beyond the SM SM symmetry (broken)

5 Fundamental Symmetries & Cosmic History Electroweak symmetry breaking: Higgs? Baryogenesis: When? CPV? SUSY? Neutrinos? WIMPy D.M.: Related to baryogenesis? New gravity? Lorentz violation? Grav baryogen?? Weak scale baryogenesis Beyond the can SMbe tested experimentally SM symmetry (broken) Cosmic Known Energy Unknowns Budget

6 Fundamental Symmetries & Cosmic History Present universe Early universe 4! A near miss for grand unification 2 g i Standard Model Gravity Is there unification? What new forces are responsible? Weak scale log 10 (µ / µ 0 ) High energy desert Planck scale

7 Fundamental Symmetries & Cosmic History 2 Present universe G F ~ 1 M WEAK Weak Int Rates: Solar burning Element abundances 4! Weak scale 2 unstable: g i Standard Model Early universe Unification Neutrino mass Origin of matter Why is G F so large? High energy desert Weak scale log 10 (µ / µ 0 ) Planck scale

8 There must have been additional symmetries in the earlier Universe to Unify all matter, space, & time Stabilize the weak scale Produce all the matter that exists Account for neutrino properties Give self-consistent quantum gravity Supersymmetry, GUT s, extra dimensions

9 What are the new fundamental symmetries? Collider experiments (pp, e + e -, etc) at higher energies (E >> M Z ) Two frontiers in the search Indirect searches at lower energies (E < M Z ) but high precision Large Hadron Collider Ultra cold neutrons High energy physics CERN LANSCE, NIST, SNS, ILL Particle, nuclear & atomic physics

10 Precision Probes of New Symmetries New Symmetries Electroweak symmetry breaking: Higgs? 1. Origin of Matter " µ 2. Unification & gravity 3. Weak scale stability 4. Neutrinos µ " " 0 µ " " e " µ W " Beyond the SM SM symmetry (broken)

11 Precision Probes of New Symmetries Radiative corrections Direct Measurements Precision Probing Fundamental measurements predicted Symmetries a range beyond for m t before the SM: top quark discovery muse t >> precision m b! lowenergy measurements m t is consistent with that range to probe virtual effects of new symmetries & It compare didn t have with to collider be that way results Stunning SM Success J. Ellison, UCI

12 Precision, low energy measurements can probe for new symmetries in the desert Precision ~ Mass Scale " NEW = #ONEW O SM $ % ' ) & ( M M *, + 2 M=m µ δ ~ 2 x 10-9 δ exp ~ 1 x 10-9 M=M W δ ~ 10-3 Interpretability Precise, reliable SM predictions Comparison of a variety of observables Special cases: SM-forbidden or suppressed processes

13 II. Prime suspect: Supersymmetry

14 SUSY: a candidate symmetry of the early Universe Unify all forces Protect G F from shrinking Produce all the matter that exists 3 of 4 Yes Maybe so Account for neutrino properties Give self-consistent quantum gravity Maybe Probably necessary

15 Couplings unify with SUSY Present universe Early universe Standard Model 4! g i 2 Supersymmetry High energy desert Weak scale log 10 (µ / µ 0 ) Planck scale

16 SUSY protects G F from shrinking " NEW H 0 H 0 " NEW H 0 H 0 "M 2 WEAK ~ M 2 $ M 2 + log terms # # =0 if SUSY is exact

17 SUSY may help explain observed abundance of matter Cold Dark Matter Candidate χ 0 Lightest SUSY particle Baryonic matter: electroweak phase transition Unbroken phase Broken phase t CP Violation H

18 SUSY: a candidate symmetry of the early Universe Supersymmetry gauginos Higgsinos Fermions e L,R, q L,R W, Z,!, g H u, H d Bosons e L,R, q L,R W, Z,!, g H u,h d sfermions W, Z,!, H Charginos, u, d " # ±, # 0 neutralinos

19 SUSY must be a broken symmetry 105 new parameters: masses, mixing angles, CPV phases (40) Superpartners have not been seen Theoretical models of SUSY breaking Models: relate weak scale parameters to each other at high scales ( hidden sector ) M e >> m e SUSY Breaking M q >> m q M " >> M W,Z,# Visible World Hidden World How is SUSY broken? Flavor-blind mediation

20 SUSY and R Parity P = (!1) 3(B! L) (!1) 2S R If nature conserves P R vertices have even number of superpartners Consequences Lightest SUSY particle viable dark matter candidate Proton is stable (! 0 ) is stable Superpartners appear only in loops

21 R-Parity Violation (RPV) ΔL=1 W RPV = λ ijk L i L j E k + λ / ijk L i Q j D k +µ / i L i H u + λ // ijku i D j D k ΔB=1 proton decay: Set λ // ijk =0 L i, Q i E i, U i, D i SU(2) L doublets SU(2) L singlets

22 RPV : Four-fermion Operators! e e! k e R d e! j q L λ 12k λ 12k λ / 1j1 λ / 1j1 µ!! µ e! d ΔL=1 ΔL=1! 12k = " 12k 2! 2 1j 1 4 2G F M e k R / = / " iji G F M q j L

23 III. SUSY & Weak Decays

24 Weak Decays & SUSY d " u e # $ e s " u e # $ e b " u e # $ e u c t ( ) " V ud V us V ub %" d% $ ' $ ' V cd V cs V cb s $ ' $ ' # V td V ts V tb &# b& " µ µ " " µ µ " β-decay W " " 0 " µ " e µ n " p e # $ e A(Z,N) " 0 " A(Z #1,N " +1) e + e $ e " % + µ " % 0 e + " e $ +L e " # "O SUSY +L~ O SM SUSY G F " G F µ = V ud 1+ #r " $ #r µ ( ) New physics

25 SUSY Radiative Corrections Δr µ Propagator " µ " # " e W " W " + " µ e " " e W " W " +L µ " " 0 µ " " e Vertex & External leg " µ µ " " e " µ W " " 0 µ " + " µ µ " " + W " µ " " e +L " 0 " µ " 0 " e Box " µ " e +L µ " " #

26 Weak Decays & SUSY " µ µ "! d " u e # $ e s " u e # $ e b " u e # $ e! " e e e β-decay! " µ k e W " R λ" 0 12k λ 12k " µ µ! µ n " p e # $ e! µ A(Z,N) " 0 " A(Z #1,N " +1) e + j e $ q L e " % + µ " % 0 e + " e λ $ / 1j1 +L e d e! λ / 1j1 " # d "O SUSY R Parity Violation +L~ O SM u c t ( ) M W " Flavor-blind SUSYbreaking V ud V us V ub %" d% $ ' $ ' V cd V cs V cb s CKM Unitarity $ ' $ ' # V td V ts V tb &# b& CKM, (g-2) µ, M W, M t, G F " G F µ = V ud 1+ #r " $ #r µ ( ) M µ L > M q L Kurylov, R-M, Su APV π l2 SUSY No RPV long-lived LSP New or SUSY physics DM Kurylov, R-M

27 Weak decays d " u e # $ e s " u e # $ e b " u e # $ e u c t ( ) " V ud V us V ub %" d% $ ' $ ' V cd V cs V cb s $ ' $ ' # V td V ts V tb &# b& kaon decay K + " # 0 e + $ e G F K G F µ = V us 1+ "r K # "r µ ( ) Value of V us important New Situation physics: Unsettled too small

28 CKM Summary: PDG04 UCNA

29 CKM Summary: New V us & τ n? V us & V ud theory? New τ n!! New 0+ info UCNA

30 Weak decays & new physics Correlations d " u e # $ e s " u e # $ e b " u e # $ e u c t ( ) " V ud V us V ub %" d% $ ' $ ' V cd V cs V cb s $ ' $ ' # V td V ts V tb &# b& " µ µ " " e " µ W " " 0 µ " u d u " 0 " # " e " e "O SUSY +L~ O SM +L SUSY dw "1+ a r p e # p r $ E e E $ + A r % n # r p e E e + L Non (V-A) x (V-A) interactions: m e /E β-decay at SNS, RIACINO?

31 Weak decays & SUSY : Correlations Chiral symmetry breaking in SUSY Is χsb / m f as in SM? u u " 0 " e " e Large χ symmetry breaking: New SUSY models " r J Profumo, R-M, Tulin d " # Future exp t? r J " r p # Collider signature: Mass suppressed χ symmetry breaking: alignment models SUSY but only SMlike Higgs

32 Pion leptonic decay & SUSY SM strong interaction effects: parameterized by F π Hard to compute " l " SM radiative corrections also have QCD effects " " l " +L To probe effects of new physics in Δ NEW we need to contend with QCD u d u " 0 " # " l " l l "

33 Pion leptonic decay & SUSY New TRIUMF, PSI u Leading QCD uncertainty: Marciano & Sirlin Probing Slepton Universality " 0 " e u " 0 " µ " " l " +L Can we do better on? Tulin, Su, R-M Prelim u " e vs u " µ d " # d " # µ " Min (GeV)

34 Lepton Flavor & Number Violation µ e Present universe Early universe " " Y #1 MEG: B µ!eγ ~ 5 x µ e " L #1 R = B µ!e B µ!eγ " S #1 A( Z,N) A( Z,N)?? MECO: B µ!e ~ 5 x Also PRIME Weak scale log 10 (µ / µ 0 ) Planck scale

35 µ Lepton Flavor & Number Violation 0νββ decay e LFV Probes of RPV: Raidal, Santamaria; Cirigliano, Kurylov, R-M, Vogel µ!eγ " MEG: Light B ν µ!eγ ~ 5 x M exchange? µ e u u ( ) A( Z,N) A Z,N " M W " W " e " d d d " 0 d u u λ / k11 ~ for for m SUSY ~ ~ 11 TeV " µ e e e " * " * " ## µ e e + e + Heavy particle exchange? MECO: B µ!e ~ 5 x Logarithmic enhancements of R Low scale LFV: R ~ O(1) GUT scale LFV: R ~ O(α)

36 Lepton Flavor & Number Violation " " " N N N N N N Short distance contributions Long range nuclear effects (π s) Faessler et al Prezeau, R-M, Vogel

37 Lepton Flavor & Number Violation λ 111 / ~ 0.06 for m SUSY ~ 1 TeV 0νββ signal equivalent to degenerate hierarchy Loop contribution to m ν of inverted hierarchy scale Effective!! Mass (mev) Inverted Normal Minimum Neutrino Mass (mev) U e1 = "m 2 = 70 mev2 sol U e2 = 0.5 "m 2 = 2000 mev2 atm U e3 = 0 Degenerate

38 IV. SUSY & PVES

39 Q W and SUSY Radiative Corrections Tree Level Q W f = g V f g A e Radiative Corrections Flavor-dependent Q W f =! PV (2I 3 f " 4Q f # PV ) +! f sin 2! W Normalization Constrained by Z-pole precision observables Scale-dependent effective weak mixing Flavor-independent

40 SUSY Radiative Corrections Propagator " # Z 0 " " + f f + Z 0 e " " +L e + f f Vertex & External leg Box " 0 e " " f f " # Z 0 Z 0 + " +L e " e f +L " f f " # f f

41 Probing SUSY with PV en Interactions No SUSY dark matter " # Z 0 " + f SUSY " + e loops " f Z 0 e " " +L e + f f χ 0 -> eµ + ν e ν is Majorana! e e! RPV 95% e CL k fit to λ R weak 12k λ decays, M W, etc. 12k µ!! µ Kurylov, Su, MR-M

42 Probing SUSY with PV en Interactions Lattice for f K + δ Q W P, SUSY / Q W P, SM Large N C for f K + δ Q W e, SUSY / Q W e, SM

43 Probing SUSY with PV en Interactions λ 12k ~ 0.3 for m SUSY ~ 1 TeV & δq We / Q W e ~ 5% Kurylov, Ramsey-Musolf, Su 0νββ sensitivity 95% C.L. JLab 11 GeV Møller λ 111 / ~ 0.06 for m SUSY ~ 1 TeV

44 Probing SUSY with PV en Interactions λ 12k ~ 0.3 for m SUSY ~ 1 TeV & δq We / Q W e ~ 5% 0νββ sensitivity λ 111 / ~ 0.06 for m SUSY ~ 1 TeV LFV Probes of RPV: µ!eγ LFV Probes of RPV: µ!e λ k31 ~ 0.15 for m SUSY ~ 1 TeV λ k31 ~ 0.03 for m SUSY ~ 1 TeV

45 Comparing Q w e and Q W p Kurylov, R-M, Su "Q W p,susy Q W p,sm Νο SUSY dark matter Linear collider DIS Parity SUSY loops E158 &Q- Weak JLab Moller RPV 95% CL "Q W e,susy Q W e,sm

46 Comparing A d DIS and Q w p,e e RPV p Loops

47 Low Energy Probes of SUSY We re making progress won t leave until the job is done and open to new ideas.