nagoya university k.kimura collaborated with a.takamura and t.yoshikawa
DESCRIPTION
3 rd T2KK workshop. Test of Unitarity by using Oscillations. 9/30-10/1 at Tokyo. Nagoya University K.Kimura Collaborated with A.Takamura and T.Yoshikawa Based on Phys.Lett.B642,372 (2006) and Preliminary paper. Outline of this talk. Introduction - PowerPoint PPT PresentationTRANSCRIPT
Nagoya UniversityK.Kimura
Collaborated withA.Takamura and T.Yoshikawa
Based on Phys.Lett.B642,372 (2006)and
Preliminary paper
3rd T2KK workshop
Test of Unitarity by using Oscillations
9/30-10/1 at Tokyo
Outline of this talk
Introduction Search for E and L with large ter
m CP phase effect in oscillations Simulation of CP sensitivity Correlation of CP phase with Possibility for Unitarity Test in T2KK Summary
)( 231m
cos
Introduction
Double-Chooz experiment
T2K experiment
One of the main purposes of next generation experiments is to determine the value of 1-3 mixing angle.
If , 1-3 mixing angle will be discovered in next generation experiments. In our study, we consider the case that is large and found within next ten years.
03.02sin 132
13
In the case of large , mass hierarchy is determined.CP phase can be also measured.Precision measurement of other parameters is possible.
T2KK experimentIlluminating plan with two detectors was proposed.
13
M. Ishitsuka et al, PRD72, 033003 (2005) K. Hagiwara et al, PLB637, 266 (2006)
Are there other good points for T2KK experiment ?
T2KK experiment
N. Okamura, hep-ph/0509164 Good points of
T2KK
Test of Unitarity
General feature on CP dependence
Magnitude of each coefficient
If we assume Unitarity
In superbeam experiments like T2KK, it is possible to use three kinds of neutrino oscillation channels in principle.
is the same order as , so the CP phase effect in oscillations is not so small. Is there possibility to detect CP phase effect in oscillations, independently from oscillations ? If possible, we can test the unitarity and may be obtain the clue of new physics.
A eA
e
(CP phase)
Search for E and L with large term
Region with large A
Parameter set
At first, we explore the region E and L where is large, without limiting the experiment of T2KK.
becomes large in the low energy and long baseline.
cos
KamiokaKorea
Atmospheric
Where is the best point ? Are there any chance to measure the CP phase in T2KK by using oscillations ?
Next slide
We discuss later
Analytic Estimation of the Region with large A
Effective masses
becomes largest around E=0.43GeV and L=5000km.
Approximate formula
Max
We show the energy dependence of and at L=5000km. A P
CP phase effect in oscillations
Results
At L=5000km, the average of attains to 0.1 around E=0.43GeV. As the CP phase effect remains even after averaging out, it may be observed in the atmospheric neutrino in the case of large .
A
13
4MW JPARC beam → 500kt WC Detector ( =0.085GeV) L=295km(250kt)+1000km(250kt) and L=5000km(500kt) M. Ishitsuka et al, PRD72, 033003 (2005) K. Hagiwara et al, PLB637, 266 (2006) E=0.4-10 GeV 10 years run Only oscillation Signal: CC (total rates)+QE (96bin normalization free) Background: NC events Systematics: normalization (2.5%), tilt (0.01%) Parameter uncertainty:
Software: GLoBES 3.0 P. Huber et al, hep-ph/0701187
Experimental Setup
e
%)1.0(231m
CP Sensitivity at L=295km+1000km
At L=295km+1000km, we cannot measure the CP phase effect well in oscillations because of the parameter uncertainties.
Results
90true 180true
Systematics only
+Correlation
CP Sensitivity at L=5000km
At L=5000km, there is the possibility for measuring the CP phase in oscillations without affecting the parameter uncertainties.
6060
120
Results
60 60
90true 180true
Systematics only
+Correlation
Correlation of CP phase with at small L/E
)( 231m
Same Energy Dependence
const
At small L/E, the correction term from and term have almost the same energy dependence.
Results
231m
Why so wrong at L=295km+1000km ?
Even 0.6% error of prevents the measurement of CP phase in small L/E. The degeneracy disappear in large L/E.
Correlation of CP phase with at small L/E
231m
Results
E=1GeV
)( 231m
E=10GeV
kmL 295
kmL 5000
kmL 1000
kmL 3000
CP Sensitivity at L=295km+1000km
If can be determined at the level of 0.1%, we can measure the CP phase even at L=295km+1000km by using only oscillations.
Results
90true 180true
Systematics only
+Correlation
231m
%1.0/)( 231
231 mm
1408080
Results
We obtain the information of the CP phase from oscillations when is below 0.6%.
dependence of CP sensitivity in T2KK)( 231m
15.02sin 132
)( 231m
(%) (%)
Results
We obtain the information of the CP phase from oscillations in the case of .
dependence of CP sensitivity in T2KK13%1.0/)( 2
31231 mm
03.02sin 132
Summary
6060
is largest around E=0.43GeV and L=5000km. In such region with large L/E, we can measure the CP phase without affecting the parameter uncertainties. Even in T2KK with small L/E, we will measure the CP phase by oscillations independently from channel, if is found precisely at the level of 0.1% and have the possibility for the test of unitarity.
e
ResultsA
T2KK 90true %1.0/)( 231
231 mm
80 80
231m
15.02sin 132
CP phase Effect in Atmospheric Neutrino
Probabilities in Atmospheric Neutrino
In T2KK experiment, a lot of atmospheric neutrino events can be also observed.
Atmospheric Neutrino Events
Effect of term in events
Ave~1.3 Ave~0.1
SK1489days22.5kt
T2KK3650days500kt×50
E(GeV)
L=8000km
L=9000km
L=10000km
E(GeV)
L=5000km
L=6000km
L=7000km
E(GeV)
L=2000km
L=3000km
L=4000km
cos
L=4000~6000km 9000~10000km
Ishitsuka, hep-ex/0406076
Ave~1.3 Ave~0.1
Effect of term in events
SK1489days22.5kt
T2KK3650days500kt×50
E(GeV)
L=5000km
L=6000km
L=7000km
E(GeV)
L=2000km
L=3000km
L=4000km
E(GeV)
L=8000km
L=9000km
L=10000km
Ishitsuka, hep-ex/0406076
L=2000~4000km 6000~7000km 9000~10000km
sin
Effect of term in events
Ave~0.2 Ave~1.3
cos e
SK1489days22.5kt
T2KK3650days500kt×50
E(GeV)
L=8000km
L=9000km
L=10000km
E(GeV)
L=5000km
L=6000km
L=7000km
E(GeV)
L=2000km
L=3000km
L=4000km
L=4000~6000km 9000~10000km
Ishitsuka, hep-ex/0406076
Ave~1.3 Ave~0.2
Effect of term in events
SK1489days22.5kt
T2KK3650days500kt×50
E(GeV)
L=5000km
L=6000km
L=7000km
E(GeV)
L=2000km
L=3000km
L=4000km
E(GeV)
L=8000km
L=9000km
L=10000km
Ishitsuka, hep-ex/0406076
L=2000~4000km 6000~7000km 9000~10000km
sin e
Effect of term in events
Probabilities in Atmospheric Neutrino
In T2KK experiment, a lot of atmospheric neutrino events can be also observed.
Ave~1.3 (15000events)Ave~0.1 (1000events)
SK1489days22.5kt300events
T2KK3650days500kt15000events
×50E(GeV)
L=4000km
L=5000km
L=6000km
Ishitsuka, hep-ex/0406076
cos e