[PPT] - Low energy neutrino experiments sensitivity to physics beyond the PowerPoint Presentation

SLIDE 1

Low energy neutrino experiments sensitivity to physics beyond the Standard Model

Timur Rashba MPI, Munich

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.1

SLIDE 2

Outline

Motivations Non-standard ν-e and ν-q interactions Non-standard contributions to ν-N coherent scattering Sensitivity to specific NSI scenarios: Z′, leptoquark and R-parity breaking SUSY Weak mixing angle and neutrino charge radius Summary

References:

J. Barranco, O. Miranda and TR, hep-ph/0508299, hep-ph/0702175, arXiv:0707.4319

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.2

SLIDE 3

Non Standard Interactions (NSI)

Most extensions of the SM, in particular neutrino mass theories, predict neutral current non-standard interactions (NSI) of neutrinos which can be either flavor preserving (NU – non-universal) or flavor-changing (FC). NSI effective Lagragian form: LNSI

eff = −

αβfP

εfP

αβ 2

√ 2GF (¯ ναγρLνβ)( ¯ fγρPf)

e, u, d e, u, d

b
a

Here α, β = e, µ, τ; f = e, u, d; P = L, R; L = (1 − γ5)/2; R = (1 + γ5)/2

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.3

SLIDE 4

Non Standard Interactions (NSI)

Non-standard neutral current neutrino interactions may arise: from a non trivial non-unitary lepton mixing matrix Schechter & Valle’80 in models where neutrino masses are "calculable" from radiative corrections Zee’80, Babu’88 in SUSY models with broken R-parity see review by Hirsch & Valle [hep-ph/0405015] and refs therein in unified SUSY models as a renormalization effect Hall, Kostelecky & Raby’86 . . . some other models, like left-right models, etc . . . Predictions:

In most models NSI contributions are expected to be small, e.g. being supressed by the smallness of neutrino masses, however in some models NSI is not strongly restricted

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.4

SLIDE 5

Current bounds on NSI couplings

Bounds on NSI couplings come from ν-scattering experiments: LSND, CHARM, NuTeV, MUNU, MINOS Barger et al’91, Davidson et al’03, Barranco et al’05 Friedland et al’06 e−e+ → ν¯ νγ measured at LEP Berezhiani & Rossi’02 analysis of atmospheric neutrino data Fornengo et al’02, Friedland et al’04’05 lepton flavor violating interactions, appeared at loop level from NSI, like µ capture by nuclei Davidson et al’03 Invisible Z-boson decay width including loop corrections due to NSI Davidson et al’03

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.5

SLIDE 6

Solar + KamLAND without and with NSI

★ ★

0.2 0.4 0.6 0.8 1

sin

2θSOL

10

5

10

4

∆m

2 SOL [eV 2]

★

0.2 0.4 0.6 0.8 1

sin

2θSOL

★

0.2 0.4 0.6 0.8 1

sin

2θSOL

10

6

10

5

10

4

10

3

∆m

2 SOL [eV 2]

★

0.2 0.4 0.6 0.8 1

sin

2θSOL

LMA-I LMA-0 LMA-D

Miranda, Tortola, Valle, hep-ph/0406280

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.6

SLIDE 7

Applications (not complete list!)

ν oscillations in matter

. . . , Guzzo et al’91, Fornengo et al’02, Friedland et al’04’05, Miranda et al’04, Kopp et al’07

ν scattering experiments

. . . , Barger et al’91, Davidson et al’03, Barranco et al’05, Kopp et al’07

supernovae explosion

Freedman et al’77, Fuller et al’87’88, Amanik et al’04’06, Esteban-Pretel et al’07

LEP (ILC)

Berezhiani & Rossi’02, Davidson et al’03

Early Universe

Mangano et al’06

. . .

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.7

SLIDE 8

Coherent neutrino scattering off nuclei (Henry Wong talk yesterday!)

Good statistics due to quadratic coherent enhancement Sensitivity to ν-quark couplings Coherent scattering if the momentum transfer, Q, is small, QR < 1 (R is radius of nucleus): = ⇒ ν-s doesn’t "see" structure of nucleus! For most of nuclei: 1/R ∼ 25 − 150 MeV Well satisfied for most neutrino sources like supernovae, solar, reactor and artificial neutrino sources Planned experiments to measure coherent ν-N scattering: NOSTOS, TEXONO . . . and other proposals Experimentally difficult: very low energy threshold

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.8

SLIDE 9

Proposed experiments to measure coherent ν-N scattering

TEXONO: 1kg of germanium, reactor neutrinos

hep-ex/0511001, H.Wong talk yesterday

NOSTOS: spherical TPC detector, 10 ton of Xenon

astro-ph/0511470

Stopped-π ν beam and kg-to-ton mass detector

hep-ex/0511042

beta-beams

Bueno et al, PRD’06

more ideas in the past, superconducting detector (Drukier & Stodolsky’84) acoustic (Krauss’91) cryogenic (Oberauer’02)

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.9

SLIDE 10

ν-N coherent scattering

dσ dT = G2

F M

2π ( (GV + GA)2 + (GV − GA)2 „ 1 − T Eν «2 − ` G2

V − G2 A

´ MT E2

ν

) GV = h“ gp

V + 2εuV ee + εdV ee

” Z + “ gn

V + εuV ee + 2εdV ee

” N i F V

nucl(Q2)

GA = h“ gp

A + 2εuA ee + εdA ee

” (Z+ − Z−) + “ gn

A + εuA ee + 2εdA ee

” (N+ − N−) i F A

nucl(Q2)

dσ dT (Eν, T) = G2

F M

π „ 1 − MT 2E2

ν

« × × h Z(gp

V + 2εuV ee + εdV ee ) + N(gn V + εuV ee + 2εdV ee )

i2 + + X

α=µ,τ

h Z(2εuV

αe + εdV αe ) + N(εuV αe + 2εdV αe )

i2 9 = ; Axial couplings contribution is zero or can be neglected Coherent enhancement of cross section Degeneracy in determination of NSI parameters

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.10

SLIDE 11

Resolving degeneracy

h Z(gp

V + 2εuV ee + εdV ee ) + N(gn V + εuV ee + 2εdV ee )

i2 = ˆ Zgp

V + Ngn V

˜2 εuV

ee (A + Z) + εdV ee (A + N) = const .

Solution: take two targets with maximally different k = (A + N)/(A + Z)

20 40 60 80 100 120 Z [protons] 20 40 60 80 100 120 N [neutrons]

76Ge ■

■ 28Si

k=1.15 k = 1

136Xe ■

■132Xe ■22Ne ■ 40Ar

86Kr ■

■ 208Pb

10

4 events

5 x 10

3

3 x 10

3

10

3

Tth=400eV 20 40 60 80 100 120 Z [protons] 20 40 60 80 100 120 N [neutrons]

76Ge ■

■ 28Si

k=1.15 k = 1

136Xe ■

■132Xe ■22Ne ■ 40Ar

86Kr ■

■ 208Pb

5 x 10

4 events

3 x 10

4

2 x 10

4

10

4

Tth=100eV

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.11

SLIDE 12

Estimated bounds on NSI from TEXONO-like experiment (Ge+Si)

0.06
0.04
0.02

0.02 0.04 0.06

εee

dV

0.06
0.04
0.02

0.02 0.04 0.06

εee

uV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

Tth = 400eV

0.6
0.4
0.2

0.2 0.4 0.6

ετe

dV

0.6
0.4
0.2

0.2 0.4 0.6

ετe

uV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

Tth = 400eV

0.06
0.04
0.02

0.02 0.04 0.06

εee

dV

0.06
0.04
0.02

0.02 0.04 0.06

εee

uV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

Tth = 100eV

0.6
0.4
0.2

0.2 0.4 0.6

ετe

dV

0.6
0.4
0.2

0.2 0.4 0.6

ετe

uV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

Tth = 100eV

76Ge+28Si Tth=400eV

|ǫdV

ee | < 0.036

|ǫuV

ee | < 0.038

|ǫdV

τe | < 0.48

|ǫuV

τe | < 0.50 76Ge+28Si Tth=100eV

|ǫdV

ee | < 0.018

|ǫuV

ee | < 0.019

|ǫdV

τe | < 0.34

|ǫuV

τe | < 0.37

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.12

SLIDE 13

Present bounds and future sensitivity to NSI

One parameter analysis to compare coherent scattering sensitivity with present bounds and νFactory sensitivity (from Davidson et al’03), see also Kropp et al, hep-ph/0702269 Present Limits ν Factory

76Ge Tth=400eV 76Ge+28Si Tth=400eV

(76Ge Tth=100eV ) (76Ge+28Si Tth=100eV ) ǫdV

ee

−0.5 < ǫdV

ee < 1.2

|ǫdV

ee | < 0.002

|ǫdV

ee | < 0.003

|ǫdV

ee | < 0.002

(|ǫdV

ee | < 0.001)

(|ǫdV

ee | < 0.001)

ǫdV

τe

|ǫdV

τe | < 0.78

|ǫdV

τe | < 0.06

|ǫdV

τe | < 0.032

|ǫdV

τe | < 0.024

(|ǫdV

τe | < 0.020)

(|ǫdV

τe | < 0.017)

ǫuV

ee

−1.0 < ǫuV

ee < 0.61

|ǫuV

ee | < 0.002

|ǫuV

ee | < 0.003

|ǫuV

ee | < 0.002

(|ǫuV

ee | < 0.001)

(|ǫuV

ee | < 0.001)

ǫuV

τe

|ǫuV

τe | < 0.78

|ǫuV

τe | < 0.06

|ǫuV

τe | < 0.036

|ǫuV

τe | < 0.023

(|ǫuV

τe | < 0.023)

(|ǫuV

τe | < 0.018)

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.13

SLIDE 14

Specific NSI scenarios

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.14

SLIDE 15

Extra heavy neutral gauge boson Z′

εuL

ee

= εdL

ee = −εuR ee = −4γ sin2 θW ρNC νN

cβ √ 24 − sβ 3 r 5 8 ! 3cβ 2 √ 24 + sβ 6 r 5 8 ! εdR

ee

= −8γ sin2 θW ρNC

νN

3cβ 2 √ 24 + sβ 6 r 5 8 !2 , γ = (MZ/MZ′)2

1
0.5

0.5 1

cosβ

200 400 600 800 1000 1200 1400 1600

MZ’ (GeV)

beta beam 15 keV TEXONO 100 eV beta beam 5 keV TEXONO 400 eV Stopped pion source Double Chooz current limit

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.15

SLIDE 16

Leptoquark εuV = λ2

u

m2

lq

√ 2 4GF , εdV = λ2

d

m2

lq

√ 2 4GF

2 4 6

mass*time/(M 0 year)

0.01 0.015 0.02 0.025

λd

2 / (m lq/300 GeV) 2

Current limit beta beam 15 keV TEXONO 100 eV beta beam 5 keV TEXONO 400 eV Stopped pion case

In some models leptoquark can be light See Dorsner et al’05

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.16

SLIDE 17

SUSY with broken R-parity

R-parity violating MSSM (imposing baryon number conservation) with a superpotential that contains the following L- violating terms: λijkLi

LLj L ¯

Ek

R,

λ′

ijkLi LQj L ¯

Dk

R

2 4 6

mass*time/(M0 year)

0.001 0.01

|λ

’dL

2

1j1 - λ ’dR

2

11k | λ

’dL

2

1j1 current limit

TEXONO 100 eV beta beam 5 keV TEXONO 400 eV beta beam 15 keV Stopped pion source

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.17

SLIDE 18

The νee interaction and sin2 θW

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.18

SLIDE 19

The νee interaction and sin2 θW

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55

sin

2θW

1 2 3 4 ∆ χ

2 global Irvine Krasnoyarsk Rovno LAMPF LSND MUNU

1 σ

90 % C. L.

Barranco, Miranda, TR, arXiv:0707.4319: sin2 θW = 0.259 ± 0.025 not competitive to NuTeV (sin2 θW (on-shell)=0.2277 ± 0.0013 ± 0.0009), Moller scattering and atomic parity violation (1%), but different channel: νee scattering!

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.19

SLIDE 20

The νee interaction and a νe effective charge radius

2
1

1 2 3 4

<r

2>

1 2 3 4 5 6

∆ χ

2

1 σ

90 % C. L.

global Irvine Krasnoyarsk Rovno LAMPF LSND MUNU

The existence of a non-zero neutrino charge radius as a gauge-independent quantity has been the subject of a recent polemic: J. Bernabeu, J. Papavassiliou and J. Vidal,

Phys. Rev. Lett. 89, 101802 (2002); arXiv:hep-ph/0303202. K. Fujikawa and R. Shrock,
Phys. Rev. D 69, 013007 (2004); arXiv:hep-ph/0303188.

If the neutrino charge radius exists it should have a value of ≈ 0.4 × 10−32 cm2 and it would modify the νee by changing the value of sin2 θW to sin2 θW = sin2 θW + δ with the radiative correction δ = ( √ 2πα/3GF )r2

νe = 2.3796 × 1030 cm2 × r2 νe

ur result: −0.13 × 10−32 cm2 < r2

νe < 3.32 × 10−32 cm2 at 90% C.L.

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.20

SLIDE 21

νe-e scattering, sin2 θW and r2

νe Experiment Energy Events sin2 θW r2

νe >

r2

νe <

MeV 10−32 cm2 10−32 cm2 90% C.L. 90% C.L. LAMPF 7 − 60 236 0.249 ± 0.063 −3.56 5.44 LSND 10 − 50 191 0.248 ± 0.051 −2.97 4.14 1.5 − 3.0 381 Irvine 8 > < > : 9 > = > ; 0.29 ± 0.05 N/A N/A 3.0 − 4.5 77 Krasnoyarsk 3.15 − 5.175 N/A 0.22+0.7

−0.8

−7.3 7.3 Rovno 0.6 − 2.0 41 N/A N/A N/A MUNU 0.7 − 2.0 68 N/A N/A N/A

Global

0.259±0.025

0.13

3.32

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.21

SLIDE 22

Conclusions

Non-standard interactions in the neutrino sector are predicted in models beyond the SM and can be rather large NSI can play significant role in astrophysical environments Coherent neutrino scattering off nuclei gives a new sensitive probe to ν-quark vector couplings Combined analysis of all νee scattering experiments gives new limit to νe effective charge radius

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.22

SLIDE 23

neutrino-nuclei scattering

76Ge+28Si Tth=400eV 76Ge+28Si Tth=100eV

ǫdV

ee

|ǫdV

ee | < 0.036

|ǫdV

ee | < 0.018

ǫuV

ee

|ǫuV

ee | < 0.038

|ǫuV

ee | < 0.019

ǫdV

τe

|ǫdV

τe | < 0.48

|ǫdV

τe | < 0.34

ǫuV

τe

|ǫuV

τe | < 0.50

|ǫuV

τe | < 0.37

ǫdV

ee

−0.002 < ǫdV

ee < 0.034

−0.0009 < ǫdV

ee < 0.016

ǫdV

τe

|ǫdV

τe | < 0.1

|ǫdV

τe | < 0.074

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.23

SLIDE 24

NSI with d-quark only εdV

τe

versus

εdV

ee

0.01 0.02 0.03 0.04 0.05

εee

dV

0.1
0.05

0.05 0.1

ετε

dV

Tth = 400eV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

0.01 0.02 0.03 0.04 0.05

εee

dV

0.1
0.05

0.05 0.1

ετε

dV

Tth = 100eV

76Ge [90% C.L.] 76Ge [99%] 76Ge+ 28Si [90%] 76Ge+ 28Si [99%]

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.24

SLIDE 25

Example: Rp / parity violating SUSY

Non-standard neutrino-electron and neutrino quark interactions: L = λijk˜ ek∗

R (¯

νi

L)cej L + λ′ ijk ˜

dj

L ¯

dk

Rνi L + . . .

Barger, Giudice & Han’89 See e.g. Roulet’91, Amanik et al’05

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.25

SLIDE 26

Solar ν oscillations and NSI HNSI = √ 2GFNf

ε

ε ε′

.

with,

ε = − sin θ23 εfV

eτ

ε′ = sin2 θ23 εfV

ττ − εfV ee

and

εfV

ττ = εfL ττ + εfR ττ

Note:

ν oscillations are sensitive mainly to vector couplings because matter is

not polarized.

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.26

SLIDE 27

Current bounds on NU NSI ν-q couplings from Davidson et al’03

vertex current limits future limit (¯ uγρPu)(¯ ντ γρLντ) |εuL

ττ | < 1.4

−0.3 < εuL

ττ < 0.25

|εuR

ττ | < 3

−0.25 < εuR

ττ < 0.3

(Γinv)∗) KamLAND and SNO/SK ( ¯ dγρLd)(¯ ντγρLντ ) |εdL

ττ | < 1.1

−0.25 < εdL

ττ < 0.3

|εdR

ττ | < 6

−0.3 < εdR

ττ < 0.25

(Γinv)∗) KamLAND and SNO/SK (¯ uγρPu)(¯ νµγρLνµ) |εuL

µµ| < 0.003

|εuL

µµ| < 0.001

−0.008 < εuR

µµ < 0.003

|εuR

µµ | < 0.002

NuTeV s2

W in DIS at νFactory

( ¯ dγρPd)(¯ νµγρLνµ) |εdL

µµ| < 0.003

|εdL

µµ| < 0.0009

−0.008 < εdR

µµ < 0.015

|εdR

µµ| < 0.005

NuTeV s2

W in DIS at νFactory

(¯ uγρPu)(¯ νeγρLνe) −1 < εuL

ee < 0.3

|εuL

ee | < 0.001

−0.4 < εuR

ee < 0.7

|εuR

ee | < 0.002

CHARM s2

W in DIS at νFactory

( ¯ dγρPd)(¯ νeγρLνe) −0.3 < εdL

ee < 0.3

|εdL

ee | < 0.0009

−0.6 < εdR

ee < 0.5

|εdR

ee | < 0.005

CHARM s2

W in DIS at νFactory

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.27

SLIDE 28

Current bounds on FC NSI ν-q couplings from Davidson et al’03

vertex current limits future limit (¯ uγρPu)(¯ ντγρLνµ) |εuP

τµ | < 0.05

|εuP

τµ | < 0.03

NuTeV s2

W in DIS at νFactory

( ¯ dγρPd)(¯ ντ γρLνµ) |εdP

τµ | < 0.05

|εdP

τµ | < 0.03

NuTeV s2

W in DIS at νFactory

(¯ uγρPu)(¯ νµγρLνe) |εuP

µe | < 7.7 × 10−4

(Tiµ → Tie)∗) ( ¯ dγρPd)(¯ νµγρLνe) |εdP

µe | < 7.7 × 10−4

(Tiµ → Tie)∗) (¯ uγρPu)(¯ ντ γρLνe) |εuP

τe | < 0.5

|εuP

τe | < 0.03

CHARM s2

W in DIS at νFactory

( ¯ dγρPd)(¯ ντ γρLνe) |εdP

τe | < 0.5

|εdP

τe | < 0.03

CHARM s2

W in DIS at νFactory

All these bounds are derived taking one parameter at a time! NSI couplings with νµ are already strongly restricted See Davidson et al’03 [hep-ph/0302093] for NSI neutrino-electron couplings bounds

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.28

SLIDE 29

Neutrino-nuclei interaction

LNSI

νHadron = − GF

√ 2 X

q=u,d α,β=e,µ,τ

ˆ ¯ ναγµ(1 − γ5)νβ ˜ “ εqL

αβ

ˆ ¯ qγµ(1 − γ5)q ˜ + εqR

αβ

ˆ ¯ qγµ(1 + γ5)q ˜” , LNC

νHadron = − GF

√ 2 X

q=u,d α,β=e,µ,τ

ˆ ¯ ναγµ(1 − γ5)νβ ˜ “ fqL

αβ

ˆ ¯ qγµ(1 − γ5)q ˜ + fqR

αβ

ˆ ¯ qγµ(1 + γ5)q ˜” , fuL

αα = ρNC νN

„ 1 2 − 2 3 ˆ κνN ˆ s2

Z

« + λuL + εuL

αα

fdL

αα = ρNC νN

„ − 1 2 + 1 3 ˆ κνN ˆ s2

Z

« + λdL + εdL

αα

fuR

αα = ρNC νN

„ − 2 3 ˆ κνN ˆ s2

Z

« + λuR + εuR

αα

fdR

αα = ρNC νN

„1 3 ˆ κνN ˆ s2

Z

« + λdR + εdR

αα

Low energy neutrino experiments sensitivity to physics beyond the Standard Model – p.29