KamLAND

(µ) ν e RSFP + ν e RSFP(Resonant Spin Flavor Precession) ν e RSFP 1. ν e ν µ ν e RSFP.ν e νµ ν e νe µ

KamLAND νe KamLAND (ʼ4). kton-day 8.3 < E ν < 14.8 MeV candidates Φ(νe) < 37 cm - s -1 P(νe νe) <.8-4 (9% C.L.) 7 5 5 kton-day ( )

ν e 1. cm - s -1 (9% C.L.) (E ν > 19.3 MeV) for constant SN rate model Super-Kaimiokande SK νe Reactor νe 8 B solar νe hep νe Atmospheric νe KamLAND

ν e β : νe + p e + + n γ e + e - γ : e + + e - γ Eprompt = E ν - Tn -.784 MeV ν e p n μsec σtot () = π /me 5 f R τn γ Ee () pe () τn = 885.7 ±.8 sec d cm ] 4 Cross Section [! Cross Section 5 15 : n + p d + γ Edelayed =. MeV.% 5 4 6 8 1 14 16 18 Neutrino Energy [MeV]

νe 7.5 < Eprompt < 3. MeV 1.8 < Edelayed <.6 MeV.5 < ΔT <. µsec ΔR < 16 cm Rprompt, Rdelayed < 6 cm µ (ΔQ> 6 p.e.) sec veto µ (ΔQ< 6 p.e.) Events/.1MeV 3 Reactor e w/ oscillation Geo e 8 B = 8 e B e (.8 SRN (LL model) -4 ) 3m sec veto e - ν µ 1 C µ - τ=.μsec X µ 1-1 ν µ ν e β,γ 3m - 4 6 8 1 14 E prompt [MeV] 7.5MeV

1.. 3. 9 Li 4. 5.

1. NUANCE ( ) Geant4 NC ν(ν) + 1 C ν(ν) + n + 11 C CC ν(ν) + 1 C l - (l + ) + n + + X ν + p l + + n -1 [m sec sr GeV] 4 3 1 µ µ e e NUANCE Fermi gas model νe, ν µ, νe, ν µ / π CH(.78g/cm 3 ) 9m -1 - -3-4 -5-6 -7-8 -9 - -11-1 : % M.Honda, et al., ʼ5-1 1 3 4 neutrino energy [GeV] full mixing 5% (CC )

.6% L.A.Ahrens, et al., (ʼ87) Q <.45 (GeV/c) 71.7% σ =. (flux)+.6 ( ) Events/.5(GeV/c) 8 6 4 71.7% = 8.7% cm /nucleon] -38 [ 3 1 1-1 nc free proton nc bound neutron nc bound proton -..4.6.8 1 q [(GeV/c) ] -3 1 1.5.5 33 3.5 44 4.5 55 5.5 6 [MeV] E µ 6

5% E <.4 GeV 18.3% flux : % : 5% : 5% 59.4% Event/.5GeV 9 8 7 6 18.3% cm /nucleon] -38 3 1 cc free proton cc bound neutron cc bound proton 5 4 3 [ 1-1 1.1..3.4.5.6.7.8.9 1 Energy [GeV] - -3 1 1.5.5 33 3.5 44 4.5 55 5.5 6 E µ [MeV] 6

Events/.5MeV 14 /ndf =.3 / 7 1 8 6 4 Probability = 17.% f(e) = 171.19 exp(-e / 19.76) /ndf = 9.8 / 7 Probability = 19.8% f(e) = -.9 E +.7 KamLAND σ = 7/7= 19.% 3 4 5 6 7 8 9 E prompt [MeV] (5kton-day) NUANCE σ = 8.7% 7.5 < Eprompt < 15. MeV 7.5 < Eprompt < 3. MeV 11.9 ± 3.4 7. ± 7.7 1.6 ± 1. 3.8 ±.3 1

. μ μ MUSIC/MUSUN (3 ) Geant4 n n p Events/7MeV 9 8 7 6 5 4 3 Measurement MC (tracked muon) MC (untracked muon) 3 4 5 6 7 Visible Energy (MeV) (5kton-day) 3 Events/m 3 35 4 45 5 55 6 65 7 Prompt Event Radius (cm) 7.5 < Eprompt < 15. MeV 7.5 < Eprompt < 3. MeV 1. ± 1.. ±..5 1.5 1.5 Measurement MC (tracked muon) MC (untracked muon)

3. 9 Li 9 Li μ 6 dq > events /.1 sec 4 35 3 5 15 p.e. μ 9 Li / ndf 3.49 / 18 9 8 9 He/ Li Li 959.1 ± 33.3 Offset 5.79 ±.84 β n τ = 57. msec, Q = 13.6 MeV, β - + n 6 dq < events /.1 sec 5 4 35 3 5 15..4.6.8 1 1. 1.4 1.6 1.8 time difference from muon [sec] p.e., dl < 3 m μ 3m 9 Li / ndf 1.43 / 18 9 8 9 He/ Li Li 336.6 ± 6. Offset 33.51 ± 1.59 μ 959.1 ± 33.3 sec veto.4 ±.1 μ 336.6 ± 6. 3m sec veto 14.9 ± 1. 7.5 MeV 19.7% 3. ±.3 events / bin 5..4.6.8 1 1. 1.4 1.6 1.8 time difference from muon [sec] 45 4 35 3 5 15 3m 6 dq < p.e 95.8 % within 3m 95.8% 5 3 4 5 6 7 8 9 distance from muon track [cm]

4. νe neutrino spectrum [/fission/mev] 1-1 - -3-4 -5 νe 35 U 38 39 41 U Pu Pu Events/.1MeV 3 1 KamLAND -6 4 6 8 neutrino energy [MeV] 8MeV Double Chooz (hep-ex/453) -1-4 6 8 1 14 E prompt [MeV] 1.5 ±.5

5. Events/.MeV 5 15 7.5MeV 3MeV.sec 1.sec 3 161 ->.161 Events/.4sec 5 15 161 ->.161 5 5 5 15 5 3 E prompt [MeV]..4.6.8 1 1. 1.4 1.6 T [sec]. < ΔT < 1. sec 1/. ±.1

7.5 Eprompt 15. MeV 7.5 Eprompt 3. MeV 11.9 ± 3.4 7. ± 7.7 1.6 ± 1. 3.8 ±.3 1. ± 1.. ±. 9 Li 3. ±.3 3. ±.3 1.5 ±.5 1.5 ±.5. ±.1. ±.1 19. ± 3.7 37.5 ± 8.3

7.5 < Eprompt < 15. MeV 19.3 ± 3.7 ( ) σ σ = Confidence interval P (N) = σ = 15.8 8.3 dσ de ν SdE ν 15.8 8.3 SdE ν 8.89-4 cm ( νe) ={6.88-4 cm ( 8 Bνe) 1 (ν Nexp ) πσ e σ ν N (N unknown σ sys ) +(N BG σ BG ) BPS8(GS) 8 Bνe W.T.Winter, et al.(ʼ6) νe Lawrence Livermore group (T.Totani, et al., ʼ98) N! e ν dν Nunknown : 8 Bνe or νe ( ) NBG (19.3 ) N exp = Nunknown + NBG σsys =.% σbg = 19.%

Events/MeV 1 8 B (9% C.L.).3 events SRN (9% C.L.) 11. events Reactor 1.5 events 9 Li 3. events Neutral Current 11.9 events Charged Current 1.6 events 8 Fast Neutron 1. events Accidental. events 6 NUANCE KamLAND 4 8 9 11 1 13 14 15 E prompt [MeV] (9%C.L.) 8 Bνe KamLANDʼ4 νe Flux [cm - s -1 ] 6 37 16 νe νe 1. -4.8-4

3 7 5 5kton-day KamLAND νe 19.3 ± 3.7 (7.5 < Eprompt < 15. MeV) 37.6 ± 8.3 (7.5 < Eprompt < 3. MeV) ν e νe 1. -4 (9% C.L.) 16 cm - s -1 (9% C.L.) NC