sergio palomares-ruiz june 22, 2005 super-no a based on o. mena, spr and s. pascoli hep-ph/0504015 a...
TRANSCRIPT
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Super-NOSuper-NOAA
Based onBased on
O. Mena, SPR and S. PascoliO. Mena, SPR and S. Pascoli
hep-ph/0504015hep-ph/0504015
a long-baseline neutrino a long-baseline neutrino experimentexperiment
with two off-axis detectorswith two off-axis detectors
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
What we know and what we do What we know and what we do not know about neutrinosnot know about neutrinos
We We don’t knowdon’t know if there are sterile neutrinos if there are sterile neutrinos
We We don’t knowdon’t know what the absolute mass of neutrinos is what the absolute mass of neutrinos is
We We don’t knowdon’t know what is their nature: Majorana or Dirac what is their nature: Majorana or Dirac
We We don’t knowdon’t know what is the mass mechanism what is the mass mechanism
We We knowknow that neutrinos do oscillate: have mass that neutrinos do oscillate: have mass
We We knowknow that there are only 3 light active neutrinos that there are only 3 light active neutrinos
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Solar sector
m221 = (7.6 - 8.6) 10-5
eV2
sin2 12 = (0.28 – 0.33)
Reactor sector
sin2 13 < 0.041
Atmospheric sector
| m231 | = (1.5 – 3.4) 10-3 eV2
sin2 223 > 0.92 We We don’t knowdon’t know the octant of the octant of 2323 We We don’t knowdon’t know whether there is CP violation in the lepton sector whether there is CP violation in the lepton sector We We don’t knowdon’t know the type of mass hierarchy the type of mass hierarchy We We don’t knowdon’t know whether whether 1313 is different from 0 is different from 0
We We knowknow
O. Mena and S. J. Parke, Phys. Rev. D69:117301, 2004
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
DegeneraciesDegeneracies
((2323 , , /2 - /2 - 2323) )
(( , , 1313))
sign(sign( m m223131))
%
%
H. Minakata and H. Nunokawa, JHEP 0110:001,2001
~ sin
~ cos
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Resolving degeneraciesResolving degeneracies: : ((2323 , , /2 - /2 -
2323)) Atmospheric neutrino experimentsAtmospheric neutrino experiments
Sub-GeV events (solar term)Sub-GeV events (solar term) Multi-GeV events (matter effect)Multi-GeV events (matter effect)
Very long-baseline neutrino experimentsVery long-baseline neutrino experiments Through the solar term contributionThrough the solar term contribution
Neutrino factories and Neutrino factories and beams beams ee →→ and and ee →→
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Resolving degeneracies: Resolving degeneracies: (( , ,
1313)) Long-baseline neutrino experimentsLong-baseline neutrino experiments
Reduce degeneracy under special configurationsReduce degeneracy under special configurations
Reactor neutrino experimentsReactor neutrino experiments Only sensitive to Only sensitive to 1313
Atmospheric neutrino experimentsAtmospheric neutrino experiments
Neutrino factories and Neutrino factories and beams beams
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Resolving degeneracies: Resolving degeneracies: sign(sign( mm22
3131))
Atmospheric neutrino experimentsAtmospheric neutrino experiments Multi-GeV eventsMulti-GeV events
Long-baseline neutrino experimentsLong-baseline neutrino experiments Off-axis experimentsOff-axis experiments
Neutrino Factories and Neutrino Factories and beams beams
Need of matter effects → 13 0
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Off-axis conceptOff-axis concept
221
43.0
EE
2
2
22 4
1
1
2
LFlux
D. Beavis et al., BNL Proposal E-889
Neutrinos produced in two body decays: → +
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Experimental set-upExperimental set-up
NONOAA Medium energy beamMedium energy beam 50 (30) kton calorimeter50 (30) kton calorimeter L = 810 kmL = 810 km Off-axis distance = 10 kmOff-axis distance = 10 km →→ E = 2.3 GeVE = 2.3 GeV 3.7 (6.5) x 103.7 (6.5) x 102020 pot/yr pot/yr Proton Driver = Proton Driver = 18.5 (25) x 1018.5 (25) x 102020 pot/yr pot/yr
Super-NOSuper-NOA A NONOA + another off-axis detector A + another off-axis detector
with the same L/E (L = 200 km)with the same L/E (L = 200 km) We will consider 50 kton Liquid We will consider 50 kton Liquid
Argon detectors (high efficiency)Argon detectors (high efficiency) Only neutrinosOnly neutrinos 5 years5 years
NoA
2nd detector = Super-NoA
D. S. Ayres et al. [NOA Collaboration], hep-ph/0503053
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
ProbabilitiesProbabilities Up to second order in Up to second order in 1313, , 1212//1313, , 1212/A and /A and 1212LL
A. Cervera et al., Nucl. Phys. B579:17, 2000
P( → e) = x2 f2 + 2 x y f g cos( - ) + y2 g2
x ≡ sin 23 sin 213
y ≡ (m221 / m2
31) cos 23 sin 212
f ≡ sin(-AL/2)/( - AL/2)
g ≡ sin(AL/(2 ))/(AL/(2 ))
≡ m231 L / (4 E)
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
AsymmetryAsymmetry
)()(
)()(
FN
FN
LPLP
LPLPD
O. Mena, SPR and S. Pascoli, hep-ph/0504015
tan
11
21FFNN LALA
D
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
O. Mena, SPR and S. Pascoli, hep-ph/0504015
tan
11
42
12sin
2
1)cos(
sin1
2222
132
12FFNN LALA
x
yDD
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Bi-event plot for NOBi-event plot for NOAA
O. Mena, SPR and S. Pascoli, hep-ph/0504015
P = A cos cos + B sin sin + C
P = A cos cos + B sin sin + CIt collapses to a line if:
(AB - AB) cos sin
B = AB = -A
cos sin
NONOAA 0.9 <
<1.3
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Bi-event plots for Super-Bi-event plots for Super-NONOAA
O. Mena, SPR and S. Pascoli, hep-ph/0504015
PF = AF cos cos + BF sin sin + CF
PN = AN cos cos + BN sin sin + CN
BF = AF
BN = AN
It collapses to a line if:
(AFB – ABF) cos sin
It is always a line
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Measurable integrated Measurable integrated asymmetryasymmetry
O. Mena, SPR and S. Pascoli, hep-ph/0504015
FoNo
FoNo
NNNN
NNNNA
//
//
PD
95% C.L.
2 analysis
99%95%90%
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
Comparison with NOComparison with NOA and A and T2KT2K pot/yr = 6.5 x 1020
pot/yr (PD) = 25 x 1020
12 km off-axis3 yrs + 3 yrs
6 yrs + 6 yrs with NOA
+3 yrs + 3 yrs
with 2nd detector at second maximum
With Super-NoAonly 5 yrs to getthere
D. S. Ayres et al. [NOA Collaboration], hep-ph/0503053
June 22, 2005June 22, 2005
Sergio Palomares-Sergio Palomares-RuizRuiz
ConclusionsConclusions Resolving degeneracies is a crucial taskResolving degeneracies is a crucial task
Super-NOSuper-NOAA: 2 off-axis (LAr) detectors with same : 2 off-axis (LAr) detectors with same L/E using the NuMI beam L/E using the NuMI beam →→ determination of determination of sign(sign( m m22
3131) free of degeneracies) free of degeneracies
Only need of 5 years of neutrino run to resolve the Only need of 5 years of neutrino run to resolve the type of hierarchy down to sintype of hierarchy down to sin22 2 21313 = 0.02 with = 0.02 with Proton Driver (for all values of Proton Driver (for all values of ))
Better capabilities than NOBetter capabilities than NOA + T2K at HK for A + T2K at HK for determining the type of mass hierarchydetermining the type of mass hierarchy