# Presentation: 868697

## Working Group 1 Summary: 

**                                         ****D. Casper**
**                                      ***** M. Lindner**
**                                         ****K. Nakamura**

**O****scillation Physic****s (mostly)**
**- Part 3 -**

##                    Outline:

** ****Current knowledge of masses and mixings**
-    Giunti, Maltoni
** ****Degeneracies & future LBL experiments**
-    Minakata, Sugiyama, Whisnant, Donini, Migliozzi, Winter
** ****New reactor plans & impact on LBL **
-    Yasuda, Huber, Choubey
** ****Theory &  beyond 3******** LBL oscillation physics**
-    deGouvea, Sato, Abazajian, Shrock, Ohlsson, Chen
-     ... and plenary speakers
-     ... apologies for what is not mentioned

## Knowledge of masses and mixings 

**Giunti**: _**The absolute neutrino mass scale**_
- Kinematical measurement:
-       Mainz-Troitsk: m < 2.2 eV
-        future KATRIN:  m = | mi U2ei|  < 0.3 eV
-        atmospheric splitting ~0.05 eV
-        if  m < 3 10-2     normal hierarchy
- Cosmology:  (Raffelt)
-       WMAP + 2dF + Ly mi  < 0.7 - 1.2eV
-  further improvement expected ~X5

**3******** parameters: ****m****1****, ********m****2********, ********m****2****21****, ********23****, ********12****, ********13****, ********, ********2****, **********

## 3) Neutrino less 

- 3) Neutrino less
-     double beta decay
-    (for Majorana masses)

## Giunti:

**Giunti:**

## Maltoni: Global fits

**Maltoni: **_**Global fits**_

- (3 neutrinos, ignoring LSND)

**We know it is LMA! ******** CP violation**

## Inlcluding LSND in 4 neutrino fits

**2+2 scheme:**
- ruled out by solar + atm. data
**3+1 scheme:**
- strongly disfavoured
-  tension in the data

**3+2 scheme:** fits better    cosmology
**CPT violation: ** tension in the analyses...?
****** ****MiniBooNE**

**Maltoni ******

## Impact of solar density variations:

-  8% density change affects LMA region considerably
-  requires huge magnetic fields ...  solar modelling?

## Near future Formaggio: 

_**(Awaited) results from SNO**_

**De Holanda,**
**Smirnov**
**hep-ph/0212270**

- Day – Night
- Contours (%)

- Probability
- Contours

## Future LBL experiments & degeneracies 

-  do not compare apples with pies

_**Compare only studies which**_
-  include all relevant experimental & theoretical aspects
- - have equally ambitious scenarios as a function of
-   time, technology, cost, ...  unbiased attitude

**- degeneracies**
** ****correlations**

##  bi-probability plots

****** ****bi-probability plots**

## Minakata, Yasuda: 

_**Overview of degeneracies**_

## Compare only complete studies 

-  Probabilities show only qualitative behaviour
-  Asymmetries are dangerous
-  _Perform event rate based analysis:_
-      * Include trigonometric correlations and degeneracies
-      * Include errors for external parameters (solar)
-      * Do not fix unknown parameters (e.g. =0)
-      * Include matter effects and matter profile uncertainties
-      * Do not omit relevant terms in oscillation formulae
-      * Proper statistical methods
-      * ...

**Compare only complete studies**
- (or at least ``equivalent‘‘ studies)

## Example: MINOS sin213 sensitivity

- to appear

- Example: MINOS sin213 sensitivity

-  sensitivity to some parameter combination
-  sensitivity to sin213

## Tazanakos: Updated MINOS discovery potential

**Tazanakos: ****Updated MINOS discovery potential**

- Better unit: pot
- Old limits: 7.4 1020 pot
- Asked for 25 1020 pot / 5y

## Strategies to break degeneracies  combine:

** ****Different energies**
** ****Neutrinos and anti-neutrinos**
** ****Different oscillation channels **
** ****Spectral information **
** ****Oscillation with & without matter**
** ****...****	**
-  all directions / combinations have advantages and disadvantages
-  optimization relatively clear for next generation
-      JHF-SK  ; NuMI ; reactor
-  final answer difficult for long term future (technology, ...)
-      ...but what we know is encoutaging and it can only become better

_**Strategies to break degeneracies **__****__** combine:**_

## Degeneracies session: Results of main groups agree*

**Whisnant: **_**Combining superbeams**_

**Donini: **_**Combining superbeams and the neutrino factory**_

**Migliozzi: **_**Silver channel and the neutrino factory**_

**Winter: **_**Resolving degeneracies for different values of **__****__**13**_

**Degeneracies session: **_**Results of main groups agree**__*****_

-  Impact / resoltion of degeneracies at different LBL levels:

- *) This does not mean that any study includes all relevant aspects

- Next generation

- Neutrino factory

## Combining JHF-SK &   NuMI@ 890   Synergies 

_**Combining JHF-SK &   NuMI@ 890  **__****__** Synergies**_

**Barger, Marfatia, Whisnant**
**Huber, ML, Winter**
**Minakata, Nunokawa, Parke**
**...**

## Winter

**Winter**

## +

**+**

## Donini:

**Donini:**

## New reactor ideas & impact on LBL 

**Yasuda: **_**New short baseline reactor ideas**_

## Yasuda, Suekane: 

**Yasuda, Suekane: **
_**Combine reactor with JHK-SK**_

- Very active case
- studies in different places
-  Link

## Huber: Combining beams and reactors

**Huber: **_**Combining beams and reactors**_

** ****Similar sensitivity at LMA-I und atmospheric best fit**
** ****Reactor sensitivity is less ********m****2****31**** and less ********m****2****21**** dependent**

##  JHF-SK  +  NuMI-890  +  Reactor-II perform best 

** ****JHF-SK  +  NuMI-890  +  Reactor-II perform best **
** ****Sensitivity to sgn(********m****2****) for any ********m****2****21**
** ****Sensitivity to CP violation in LMA-II region**

- Combine: Improved sin2(213) , sgn(m2) and CP limits

## Choubey: Implications of Kamland/Precision measurement of parameters before nufact

- SPMIN:
- good  sensitivity

- SPMAX:
- poor  sensitivity

**KamLAND is not**
**     ****in the ideal place!**

- LMA-I   70 km
- LMA-II  20-30 km

** ****Propose a new reactor experiment at ideal distance**
** ****HLMA ******** even some ********13**** sensitivity**

## Improving the solar parameters is important for LBL!

- Current studies assume typically a 10% relative error on solar param.
- ... which enters via correlations
- ... and contributes to the error / limitations of LBL measurements!

-  think of ideas to improve solar parameters to few % level

## Theory 

**Shrock: **_**Neutrino masses without a new energy scale**_

**Chen: **_**Neutrino masses and mixings in SO(10) models**_

** ****There exist many models for neutrino masses**

-  attractive framework for neutrino masses

-  interesting alternative to explain neutrino masses without
-      conventional see-saw in DSB framework ~TeV scales

**Dirac or Majorana?**
- Majorana: * see-saw  smallnes of neutrino masses
-                  * simplest leptogenesis scenario
-       Dirac: * other tiny Yukawa couplings exist
-                  * may be enforced by extra U(1)    (strings, ...)
-  experiments must decide   02 decay, L violation

## How small could  sin2(213)  be?

-  random mass matrices (anarchy)  predicts large mixings
-      large neutrino mixings may be rather natural
-  why is Ue3 , i.e.  sin2(213) so small?
-      expect sin2(213)  close to experimental limit
-      or some protective symmetry must operate

**How small could  ****sin****2****(2********13****)**  **be?**
- In general arbitrarily small, inlcuding zero
- Models: anarchy   close to limit
-               textures   mass ratio suppression ~ typically down to 10-2
-                                                  sin2(213) = 0 possible, requires model tuning
- Quantum corrections (RGE)  [sin2(213) ] = 10-4 ....  10-1
-  good reasons to expect sin2(213) = 10-2   reachable

## Abazajian: Cosmological energy density of neutrinos from oscillation measurements

**Sato: **_**Lepton flavour violation in long baseline experiments**_

**Ohlsson: **_**Extrinsic CPT violation in neutrino oscillations**_

-  matter violates C, CP and CPT
-  interesting theoretical consequences for oscillation formulae
-  for LBL a tiny effect  theoretical error of LBL studies

-  3 oscillation may be affected by LFV effects
-  must be included in analysis
-  less sensitivity to oscillation parameters

-  connection between cosmological energy density & oscillation
-  Future measurements of q12 and q13 will further constrain
-      the cosmological neutrino density

## Conclusions:

**Knowledge of oscillation parameters:**
-  KamLAND has established LMA region  ideal for leptonic CP violation
-  Further improvements of solar data expected (SNO)
-  MiniBooNE will clarify LSND evidence
**LBL studies have become better:**
-  Degeneracies & correlations under control
-  Strategies to break degeneracies by combining
-   e.g. Silver channels at NuFact
-  Synergies in next generation superbeams
-  New reactor experiments & superbeams are synergetic
-    sin2(213) sensitivity down to 10
**Theory:**
-  Reasons to expect sin2(213) not below this magnitude

****** ****Lets measure it with next generation experiments ******** NuFact**