miguel-angel sanchis-lozano

QWG5 DESY October 20, 2007

Miguel A. Sanchis-Lozano IFIC-Valencia

1

Miguel-Angel Sanchis-Lozano

Department of Theoretical Physics & IFICUniversity of Valencia – CSIC

Spain

A light non-standard Higgs: to be or not to beA light non-standard Higgs: to be or not to be @ a (Super) B factory*@ a (Super) B factory*

email: [email protected]

*Based on arXiv:0709.3747hep-ph/0702190, hep-ph/0610046hep-ph/020156, hep-ph/0307313

Special thanks to J.Duboscq (CLEO) for many iIluminating discussions

QWG5 DESY QWG5 DESY October 20, 2007 October 20, 2007

Miguel A. Sanchis-Lozano IFICMiguel A. Sanchis-Lozano IFIC-Valencia -Valencia

22

Light neutral Higgs scenarios

Higgs sector in the NMSSM: (seven) 2 neutral CP-odd Higgs bosons (A1,2)

3 neutral CP-even Higgs bosons (H1,2,3 )

2 charged Higgs bosons (H±)

SH

HH

H

HH

d

dd

u

uu

ˆ,ˆ,ˆ00

The A1 would be the lightest Higgs:

sMSSM1 A sinA cosA AA

Coupling of A1 to down type fermions tancos A

PQ symmetry or U(1)R slightly broken → a light pseudoscalar Higgs A1 A0

L & H

Light dark matter?

NMSSM candidate compatible with present bounds: Light neutralino with a singlet component

McElrath [hep-ph/0506151]

Light and heavy Higgsbosons can live together

tan β = v2 / v1



33

Light Higgs windows at LEP (CPV MSSM)Light Higgs windows at LEP (CPV MSSM)hep-ex/0406057hep-ex/0406057

hep-ex/0406057

CPX MSSM 95% exclusion areas using scans with different values of arg (At,b). The region excluded by Yukawa searches, Z-width

constraints or decay independent searches is shown in red

CPX MSSM 95% exclusion areas using scans with differentvalues of the top mass

Diagram illustrating the effective coupling of a Higgs mass eigenstate H1 to the Z. Only the CP-even admixture h and H couple to Z while the CP-odd A does not: hence

the coupling of the H1 is reduced wrt a CPC scenario.



44

Next-to-Minimal Supersymmetric Model (NMSSM)Next-to-Minimal Supersymmetric Model (NMSSM)

Much less constrained by LEP data Much less constrained by LEP data and B-physics observables than the MSSMand B-physics observables than the MSSM

Hiller, hep-ph/0404220

Higgs mass values allowed down to several GeVHiggs mass values allowed down to several GeV

Similarly for Similarly for Little Higgs modelsLittle Higgs models with an with an extended structure of global U(1) symmetries extended structure of global U(1) symmetries

broken both spontaneously and explicitly, broken both spontaneously and explicitly, possibly leading to light pseudoscalar particles in possibly leading to light pseudoscalar particles in

the Higgs spectrum the Higgs spectrum Kraml et al. hep-ph/0608079

Upsilon decays should be useful in the search for a light Higgs



55

FormalismFormalism

Leptonic decaysLeptonic decays



66

Mixing of a pseudoscalar Higgs AMixing of a pseudoscalar Higgs A00 and a and a b b resonanceresonance

000

000

22

22

2

bbbimmm

mimm AAA

M

000

00

0

sincos

sincos

A

AA

bb

bo

A00 , b0

unmixed states

A0 , b mixed (physical)

states

000

00

0

22

22

|sin||cos|

|sin||cos|

A

AA

bb

bo

e+ e- τ+ τ-

000

00

0

sincos

sincos

A

AA

ggg

ggg

bb

bo

0

0

dXRv

mm

b

b

|)0(|

4

32/1

2

32

22sin m

Xd = cosA tanβSmaller couplingSmaller couplingstrength than instrength than in

the MSSMthe MSSM



77

bb / A / A00 mixing mixing

Xd = 10

b mass shift ?

Hyperfine splitting m-mb

unexpectedly large/or small

broader b ?

b > [b2g]

due to the new physics contribution

Xd = cosA tanβ

Xd = 10,20,40

Possible spectroscopic consequences



88

Our proposal:Our proposal:Test of lepton universality in Test of lepton universality in leptonic decays leptonic decays

000

0

22

02

2

2

2

22

/ |sin||cos|

][|cos|1

8bA

Adl

A

m

m

v

XmR

1)(

)(/

B

B

B

BBR

em

nS

000

22

02

/ |cos||sin|

][|sin|

][

][

bA

bl

A

llB

BR

• Non-resonant decay

• Resonant decay

Wilczek formula

M1 transition probability

Mixing effect

Mixing effect

2b

32b

2M1

bs 3

41)( b

m

kQIB

QCD+binding energy effects QCD+binding energy effects small for the pseudoscalar Asmall for the pseudoscalar A00



99

Lepton universality in the SMLepton universality in the SM

ΓΓllll is an is an inclusiveinclusive quantity: quantity: ll+ + ll- - is is accompanied byaccompanied by anan infinite number of soft photonsinfinite number of soft photons

The test of lepton universality can be seen as complementary to searches for The test of lepton universality can be seen as complementary to searches for monochromatic photons in the monochromatic photons in the γγ ττττ channel (see B. Heltsley talk) channel (see B. Heltsley talk)

To order To order αα33:: ΓΓllll = = ΓΓllll 0 0 [1+[1+δδvacvac++δδvertex vertex ] ] ΓΓllll 0 0 [1+[1+δδvacvac] ]

Divergencies/singularities free at any order: Bloch and Nordsieck theorem &Divergencies/singularities free at any order: Bloch and Nordsieck theorem &

Kinoshita-Sirlin-Lee-Nauenberg theoremKinoshita-Sirlin-Lee-Nauenberg theorem

eeee )(BF)(BF)(BF

3α /4π ~ 0.17%

7.6% Contribution potentially dangerous for testing lepton universality if final-state radiation is not properly taken into account in the MC to obtain the detection efficiency in the analysis of experimental dataAlbert et al. Nucl. Phys. B 166 (1980) 460

Warning!

δ vac=δee+δ+δ+ δquarks

Neglecting phase space and helicity flip effects. Higher-order SM effects are negligible



1010

Testing Lepton UniversalityTesting Lepton Universality

Channel:Channel: * * BF[eBF[e++ee--]] BF[BF[μμ++ μμ--]] BF[BF[++--]] RR//ll

(1S) (1S) 2.38 2.38 ± 0.11 %± 0.11 % 2.60 ± 0.10 % 2.60 ± 0.10 % 0.09 ± 0.060.09 ± 0.06

(1S)(1S) 2.48 ± 0.05 %2.48 ± 0.05 % 2.60 ± 0.10 % 2.60 ± 0.10 % 0.05 0.05 ± 0.04± 0.04

(2S)(2S) 1.91 1.91 ± 0.16 %± 0.16 % 2.00 ± 0.21 %2.00 ± 0.21 % 0.05 ± 0.140.05 ± 0.14

(2S)(2S) 1.93 1.93 ± 0.17 %± 0.17 % 2.00 ± 0.21 %2.00 ± 0.21 % 0.04 ± 0.140.04 ± 0.14

(3S)(3S) 2.18 2.18 ± 0.20 %± 0.20 % 2.29 ± 0.30 %2.29 ± 0.30 % 0.05 0.05 ± 0.16± 0.16

(3S)(3S) 2.18 ± 0.21 %2.18 ± 0.21 % 2.29 2.29 ± 0.30 %± 0.30 % 0.05 0.05 ± 0.16± 0.16

1)(

)(/

B

BB

BBR

em

nS s

Lepton Universality inUpsilon decays implies

<R/l > = 0

)(BF)(BF)(BF ee

ee

* * From PDG ‘07From PDG ‘07



1111

Lepton Universality Breaking?Lepton Universality Breaking?

22

offunction decreasing (smoothly)

2/12

2

22)(

M/with

)41)(21(M

)0(4

mx

xxR

Qx

nb

em

A0 LU

R/l

0.0 0.1 0.2

R/e(1S)

R/(1S)

R/e(2S)

R/(2S)

R/e(3S)

R/(3S)

0.3 0.4

1)(/

)(/

)(/

)(/ˆ)(

)(/

llem

nS

xKB

xKB

xK

xKR

0.0-0.1



1212

Expected LUExpected LU breakingbreaking

Green line: non-resonant decayBlack line: resonant decay

Red line: sum

Xd=10, b0 = 5 MeV



1313

A closer look at the A closer look at the NMSSM parameter spaceNMSSM parameter space



1414

AA

A

A

AA

sm

sAsAs

sAv

22

2 sin22sin3

cos33

2sin3)(2

2sin)2(cos

1

λ

Aλ = -200 GeV

μ = 150 GeVAκ = -15 GeV

tanβ= 50

Aλ ~ - Κ μ / λ

Κ - (4/3) λ =0

0.1 ≤| cos A |≤ 0.5

XXdd

κλλ

tantanββ ~ ~ 1/ [1/ [Aλ+Κ (μ / λ) ] Ananthanarayan & Pandita, hep-ph/9601372Ananthanarayan & Pandita, hep-ph/9601372

Xd > 5``Xd =10



1515

In several In several NMSSM NMSSM parameter regions, it may happen at the same time: parameter regions, it may happen at the same time:

Large tanLarge tanββ (for A(for Aλλ + + κκ s ≈ 0)s ≈ 0)

0.1 ≤ | 0.1 ≤ | cos cos AA | | ≤ 0.5 ≤ 0.5 ((AA00 mainly singlet but not completely mainly singlet but not completely))

|X|Xdd| = 5 – 25 | = 5 – 25 for tanfor tanββ = 50 = 50

Low mass (e.g. 10 GeV) of the lightest CP-odd Higgs boson Low mass (e.g. 10 GeV) of the lightest CP-odd Higgs boson AA00

Low fine-tunning in order to get a Higgs-like boson explaining theLow fine-tunning in order to get a Higgs-like boson explaining the Z+b-jets event excess at LEP Z+b-jets event excess at LEP (Dermisek & Gunion, hep-ph/0510322)(Dermisek & Gunion, hep-ph/0510322)

Suggestive coincidence !

“There should be one thousand reasons for not running a B factory at There should be one thousand reasons for not running a B factory at (3S) (3S) but right now I cannot think of one”but right now I cannot think of one”



1616

SummarySummaryWhat if...What if...

there exists a light Higgs-like particle about 10 GeV?there exists a light Higgs-like particle about 10 GeV?

A high luminosity B factory would be the ideal place A high luminosity B factory would be the ideal place to discover/study it, e.g. looking at to discover/study it, e.g. looking at

- decay into - decay into ττ++ ττ-- ( ():): Lepton universality test Lepton universality test ((M.A.S.L.,M.A.S.L., arXiv:0709.3747)arXiv:0709.3747)

-- direct searches for monochromatic photons direct searches for monochromatic photons (see(see B. HeltsleyB. Heltsley talk) talk)

Dermisek, Gunion and McElrath, Dermisek, Gunion and McElrath, hep-ph/0612031hep-ph/0612031

(( also also Mangano and NasonMangano and Nason in in γγ μμμμ decays, decays, arXiv:0704:1719 arXiv:0704:1719 ))

Complementary/Implications to LHC/ILC searches!Complementary/Implications to LHC/ILC searches! + related topics: muon g-2 anomaly, light dark matter + related topics: muon g-2 anomaly, light dark matter



1717

Back upBack up



1818

Proposal of testing lepton universality (to the percent level) @ a (Super) B factoryProposal of testing lepton universality (to the percent level) @ a (Super) B factory

With the machine sitting on the With the machine sitting on the (3S)(3S) Final state & BFFinal state & BF

(3S) (3S) ππ ++ ππ - - (1S,2S) (1S,2S) →→ ++ - - ππ ++ ππ - - ++ - -

BF BF 2-4 x 10 2-4 x 10-2 -2 BF BF 2 x 10 2 x 10-2 -2 BF BF 4 - 8 x 10 4 - 8 x 10-4-4

(3S) (3S) ππ ++ ππ - - (1S,2S) (1S,2S) →→ ++ - - ππ ++ ππ -- l l ++ ll --

BF BF 10 10-1 -1 ++ -- → → ll ++ ll -- X, X, l = l = ee, , BF BF 5 - 10 x 10 5 - 10 x 10-5-5

(3S) (3S) ++ -- ++ --

BF BF 2 x 10 2 x 10-2 -2 BF BF 2 x 10 2 x 10-2 -2

(3S) (3S) ++ - - l l ++ ll -- X X → → ll ++ l l - - X, X, l = l = ee, , BF BF 2 x 10 2 x 10-3 -3

With the machine sitting on the With the machine sitting on the (4S)(4S)

(4S) (4S) ππ ++ ππ - - (1S,2S) (1S,2S) →→ ++ - - ππ ++ ππ - - ++ --

BF BF 10 10-4 -4 BF BF 2 x 10 2 x 10-2 -2 BF BF 2 x 10 2 x 10-6-6

(4S) (4S) ππ ++ ππ - - (1S,2S)(1S,2S) →→ ++ - - ππ ++ ππ -- l l ++ ll - - XX BF BF 10 10-1 -1 ++ -- → → ll ++ l l - - X, X, l = l = ee, , BF BF 2 x 10 2 x 10-7-7

Compare rates

Compare rates

Compare rates

Statistical error ≈ 0.07 / √ # fb-1

Systematic error ≤ 0.037

hep-ph/0610046



1919

Entangled both theoretically and experimentally?

b resonance A0 Higgs boson/

Searches for b states over more than 20 years

No signal found so far!

Petit bourgeois Enfant terrible

Spectroscopic consequences: quite larger or smaller hyperfine splitting

An unlikely but not impossible situation:

(ns) and b(nS) mass levels might be reversed!

Mixing

miguel-angel sanchis-lozano

Documents

lightest higgs

pseudoscalar higgs a0

higgs bosons h1

higgs bosons hthe a1

higgs mass eigenstate

higgs spectrum kraml

little higgs models

neutral cpodd higgs