The Daya Bay and T2K results on sin 2 2θ 13 and Non-Standard Neutrino Interactions (NSI)

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1 The Daya Bay and TK results on sin θ 13 and Non-Standard Neutrino Interactions (NSI) Ivan Girardi SISSA / INFN, Trieste, Italy Based on: I. G., D. Meloni and S.T. Petcov Nucl. Phys. B 886, 31 (014) 8th Neutrino Oscillation Workshop (NOW 014) Conca Spellucchia, Italy, September 7-14, 014

2 Outline Introduction The Daya Bay and the TK experiments Theory Non Standard Neutrino Interactions NSI bounds, P ee, P µe oscillation probabilities Phenomenology How NSI can decrease (I) or increase (II) I: large sin θ 13 ( ) II: small sin θ 13 ( 0.09) Summary NOW 014, I. Girardi (SISSA)

The Daya Bay experiment in China The Daya Bay experiment searching for e! e transition gives the most precise determination of θ13: sin θ13 = 0.090±0.009 ( 10%) F. P.

See Peng s talk Daya Bay: 6 reactors (D1,D,L1-L4) 6 antineutrino detectors (ADs) EH1 = AD1+AD EH = AD3 EH3 = AD4+AD5+AD6 In the one dominant mass-scale approximation

3 The Daya Bay experiment in China The Daya Bay experiment searching for e! e transition gives the most precise determination of θ13: sin θ13 = 0.090±0.009 ( 10%) F. P. An et al. (Daya Bay) PRL 11 (014) See Peng s talk Daya Bay: 6 reactors (D1,D,L1-L4) 6 antineutrino detectors (ADs) EH1 = AD1+AD EH = AD3 EH3 = AD4+AD5+AD6 In the one dominant mass-scale approximation Δm31L/(4E)=O(1) (Δm1L/(4E) 0.03 for baseline L = 1 km and mean neutrino energy <E> GeV): P ( e! e ) ' 1 sin 13 sin no sensitivity to Δm1 and θ1 no sensitivity to neutrino mass ordering no sensitivity to CPV phase δ m 4E NOW 014, I. Girardi (SISSA) F. P. An et al. (Daya Bay) PRL 11 (014) See Peng s talk

4 The TK experiment in Japan Expanding for small Δm 1L/(4E) 0.05: P ( µ! e ) ' sin 3 sin 13 sin sin 1 sin 3 sin sensitivity to sin δ m m 1 L sin 13 cos 13 sin TK appearance channel (8 events): high-energy ν µ beam from J-PARC to SK L = 95 km and <E> 0.6 GeV Δm 31L/(4E) π/ m sin (π) 1 K. Abe et al. (TK) PRL 11 (014) See Giganti s talk Searching for µ! e sin 1 =0.306, m 1 = ev, m 3 = ev, =0, 3 = /4 assuming The TK Collaboration found for NO(IO) sin 13 = ( ) δ CP (π) δ CP m3 >0 68% CL 90% CL Best fit PDG01 1σ range Latest global fit analysis θ 3 < π/4 δ 3π/ F. Capozzi et al. PRD 89 (014) NOW 014, I. Girardi (SISSA) -0.5 m3 < sin θ 13

5 Non Standard Neutrino Interactions We analyze the impact of NSI on sin θ 13 in the same conditions of the TK experiment: δ = 0, θ 3 = π/4,... Assumptions: NSI affects both neutrino production and detection matter effects are neglected The effective non-renormalizable operator neglecting matter effects parametrizing NSI at the source (s) and at the detector (d) is a 4 fermion interaction L NSI p G F " ff0 s(d) ( P L` ) f 0 P L,R f + h.c. with " M W M NSI and f, f = u, d or charged leptons M NSI 1 (10) TeV, ε αβ 10 - (10-4 ) Wolfenstein (1978), Guzzo, Masiero, Petcov (1991), Roulet (1991), Grossman (1995), J. Kopp, M. Lindner, T. Ota and J. Sato (008), T. Ohlsson (013), T. Ota and J. Sato (008), T. Ohlsson (013) NOW 014, I. Girardi (SISSA)

6 Non Standard Neutrino Interactions n! p + e + e n! p + e + µ ( ) most of ν µ s from -body decay + (K + )! µ + + µ + (K + )! µ + + e ( ) Standard NSI Standard NSI e + p! n + e + µ ( )+p! n + e + CCQE W ± exchange (target changes but no break up) µ + n! µ + p e ( )+n! µ + p most of ν e s from 3-body decay µ +! e + + e + µ K +! 0 + e + + e K. McFarland INSS 013 D. Harris Invisibles School 014 TK CC-0π (dominated by CCQE), CC-1π + (dominated by CC resonant production) and the other CC-other. See Giganti s talk Standard CCQE 0.6 GeV, see Benhar s talk Nuclear Resonance Production (target goes to excited states): CC-1π single pion,... (1π 0 comes also from NC) µ + n! µ + p + 0 (N or ) + n + + NOW 014, I. Girardi (SISSA)

7 Non Standard Neutrino Interactions In a general approach the neutrino states are superposition of orthonormal flavor eigenstates i s = i + X =e,µ, h d = h + X =e,µ, " s i = (1 + " s ) i " d h = h (1 + " d ) D. Meloni, T. Ohlsson, W. Winter and H. Zhang (010), A. N. Khan, D. M. McKay and F. Tahir (013), T. Ohlsson (013), T. Ohlsson, H. Zhang and S. Zhou (014) The oscillation probability can be obtained by squaring the amplitude P s! d = h d e ihl s i = (1 + " d ) e ihl (1 + " s ) Some NSI parameters receive contribution from the same higher dimensional operator involving u and d quarks " s e = " d e " e e i e NOW 014, I. Girardi (SISSA)

8 Non Standard Neutrino Interactions Contributions of ε s and ε d for a reactor experiment J. Kopp, M. Lindner, T. Ota and J. Sato (008) Contributions of ε s and ε d in a super-beam experiment for the appearance channel J. Kopp, M. Lindner, T. Ota and J. Sato (008) NOW 014, I. Girardi (SISSA)

9 NSI bounds and P ee oscillation probability For the NSI parameters there exist model independent of O(10 - ) " ee < 0.041, " eµ < 0.05, " e < 0.041, " s,d µe < 0.06, " s,d µµ < 0.078, " s,d µ < C. Biggio, M. Blennow and E. Fernandez-Martinez (009) with θ 13 I. G. and D. Meloni arxiv: For δ = 0 (similarly to TK), ε ee = 0 and ε eµ, ε eτ 1 P ( e! e )=1 sin ˆ 13 sin apple m sin ˆ 13 =sin 13 +4" eµ sin 13 sin 3 cos 13 cos( eµ) +4" e sin 13 cos 3 cos 13 cos( e ) T. Ohlsson and H. Zhang (009), I. G., D. Meloni and S. T. Petcov (014) Φ eµ = Φ eτ = π and large ε decreases θ 13 Φ eµ = Φ eτ + π and large ε: θ 13 = θ 13 if ε eµ = ε eτ NOW 014, I. Girardi (SISSA)

10 NSI P µe oscillation probability In the limit of δ = 0, expanding for Δm 1 L / (4E) 1 and ε eµ, ε eτ, ε µe s 1 P ( µ! e ) ' sin 3 sin 13 sin m 31L 4E + P 0 + P 1 with P 0 = 4 " s µe sin 13 sin 3 cos( s µe)sin apple m apple 4 " s µe sin 13 sin 3 sin( s µe)sin m apple cos m apple m 4" eµ sin 13 sin 3 cos( eµ ) cos 3 sin apple apple m 4" eµ sin 13 sin 3 sin( eµ )sin m cos +8" e sin 13 sin 3 cos 3 cos( e )sin apple m + O(" sin 13 )+O(" ) Dominant since Δm 31L/(4E) π/ P 1 = " s µe sin 1 cos 3 sin s µe m 1L E +" eµ sin 1 sin m 3 cos 3 cos 1L eµ + " eµ sin 1 cos 3 sin eµ m 1L E +" e sin 1 sin 3 cos 3 cos e m 1L apple sin m E apple apple m 1 sin 3 sin apple sin " e sin 1 sin 3 cos m apple 3 sin 1L e sin E m " sin 1L 13 + O(" ) + O m E m Sub-leading terms of O(Δm 1/Δm 31) I. G., D. Meloni and S. T. Petcov (014) NOW 014, I. Girardi (SISSA)

11 I: The case of sin θ 13 = 0.14 (0.17) for NO (IO) In order to allow for relative large NSI couplings: " = " eµ = " e = " s µe, = eµ = e, s µe = χ (Φ,ε) Daya Bay + TK NO + e em = e et = He s L me f em = f et, Hf s L me = χ (Φ,ε,θ 13 ) Daya Bay + TK NO q 13 free + Combined fit to the Daya Bay and TK data for fixed δ = 0, θ 3 = π/4... fixed sin θ 13 = 0.14 (0.17) from TK small tension with NSI bounds 1 Upper Bound Daya Bay TK-1.0 IO log 10 HeL e em = e et = He s L me 6 f em = f et, Hf s L me = Daya Bay TK-1.6 IO q free log 10 HeL + free sin θ 13, but constrained with the gaussian prior sin θ TK 13 = ± for NO (sin θ TK 13 = ± for IO) larger allowed parameter space as expected I. G., D. Meloni and S. T. Petcov (014) 1 Upper Bound log 10 HeL 1 GLoBES log 10 HeL 1σ σ 3σ NOW 014, I. Girardi (SISSA)

12 I: The case of sin θ 13 = 0.14 (0.17) for NO (IO) In the case of free θ 13 the sensitivity to ε is strongly reduced: vast parameter space for NSI for which the Daya Bay and TK results can be fitted simultaneously at the price of changing the value of θ 13 at the best fit sin θ 13 = (0.130) for NO (IO) PHne->neL The spectral data are well reproduced: for NO we have 1.00 Ú Ú Ú ÚÚ Ú Ú Ú Ú = EH1 = EH 6 = EH3 NSI Number of ne candidate events 8 4 SD sin θ 13 = SD sin θ 13 = TK best fit curve L GLoBES E I. G., D. Meloni and S. T. Petcov (014) NOW 014, I. Girardi (SISSA)

13 II: The case of sin θ 13 = 0.09 Minimizing the NSI effects in the P ee oscillation probability we assume: " = " eµ = " s µe, " e 6=0, eµ = s µe =, e =0-0.5 χ (ε eµ,ε eτ ) χ (ε eµ,ε eτ,θ 13 ) Daya Bay + TK NO Daya Bay + TK NO q 13 free -0.5 Combined fit to the Daya Bay and TK data for fixed δ = 0, θ 3 = π/4... log 10 HeetL Ú Ë log 10 He em L = log 10 He s mel I. G., D. Meloni and S. T. Petcov (014) log 10 HeetL Ú Ë log 10 He em L = log 10 He s mel GLoBES 1σ σ 3σ fixed sin θ 13 = 0.09 tension with NSI bounds free sin θ 13, but constrained with the prior sin θ 13 = 0.090±0.009 for NO larger allowed parameter space as expected NOW 014, I. Girardi (SISSA)

14 II: The case of sin θ 13 = 0.09 The spectral data are well reproduced: for NO using within 1σ (log 10 ε, log 10 Φ) = (-1.63,-1.63) within σ (log 10 ε, log 10 Φ) = (-1.80,-1.80) 8 8 Number of ne candidate events 6 4 Number of ne candidate events 6 4 NSI SD sin θ 13 = TK best fit curve E I. G., D. Meloni and S. T. Petcov (014) GLoBES E Message: neutrino physics is entering in the precision era and can be used to probe New Physics effects For Unitarity Violation see Ross-Lonergan s talk LED & Daya Bay: I. G. and D. Meloni arxiv: Sterile Daya Bay & JUNO: I. G., D. Meloni, T. Ohlsson, H. Zhang and S. Zhou JHEP 1408 (014) 057 NOW 014, I. Girardi (SISSA)

15 Summary The latest 3ν oscillation data give hints for a non-zero value of δ However Non Standard Neutrino Interactions have a strong impact on the correlation between sin θ 13 and δ NSI might reconcile the difference of sin θ 13 with the hypothesis of δ = 0 Further studies with more statistics needed Improvements soon... (with D. Meloni and A. Di Iura) NOW 014, I. Girardi (SISSA)

16 Acknowledgments Otranto Thanks to my supervisor S. T. Petcov to D. Meloni for the nice collaboration on NSI, to A. V. Titov and to the organizers NOW 014, I. Girardi (SISSA)

The Leptonic Dirac CP-Violating Phase from Sum Rules

The Leptonic Dirac CP-Violating Phase from Sum Rules Arsenii Titov in collaboration with I. Girardi and S.T. Petcov SISSA and INFN, Trieste, Italy XIV International Conference on Topics in Astroparticle