Alain Blondel

Detectors

UNO(400kton Water

Cherenkov)

Liquid Ar TPC(~100kton)

Alain Blondel

Far detector in second phase

Phase-I: Super-K

22.5kt (50kt)

Phase-II: Hyper-K1,000 kt

Candidate site in Kamioka

Other major goal: improve proton decay reach

limit to the size of large underground Water Cherenkovdetectors will be given by the difficulties of excavation. Max width is about 50-60 meters.=> increase high&length

Alain Blondel

SPL neutrino beam

* At 2 GeV, K production is very small Bkg of from e in the beam is small and dominatedby muon decay This can be tailored by varying the length of the decay tunnel and reduced to 0.3-0.4 % (all spectrum)

* this is a low energy beam ( <E> = 300 MeV )

e

Still work to do to fucus these…

Alain Blondel

/e Background Rejection

e/mu separation directly related to granularity of coverage. Limit is around 10-3 (mu decay in flight) SKII coverage OKOK, less maybe possible

Alain Blondel

reconstruction < 1GeV region

CC quasi elastic reaction

cos

22

pEm

mEmE

N

N

+ n → + p

-

p

(E, p)

+ n → + p +

-

p

(E, p)

Inelastic (BG)

CCqe

inelastic

~80MeV(10%)limited by Femi motion

Small BG5 X smallerfor SPL beam

SK FullDet. Sim.

Energy can be well reconstructed =>Bkg reductionprecise measurement of osc. params SENSITIVITY SIMILAR TO JHF-> HyperK

Alain Blondel

BETA Beam

new idea by P. Zucchelli

produce 6He++, store, accelerate (100 GeV/u), store

Q=3.5078 MeV T/2 = 0.8067 s

pure anti-e beam at 600 MeV

or: eFNe e

189

1810 pure e beam at 600 MeV

oscillation signal: appearance of low energy muons no opposite charge neutrinos=> no need for magnetic detectorslittle matter effects at these energieswater Cerenkov excellent for this too, same as for Superbeam.seems feasible; but cost unknown so far. Critical: duty cycle. A nice *** idea to be followed up!

6He++ Li+++ e e

Alain Blondel

Anti-Neutrino Source

Consider 6He++6Li+++ e e-

E03.5078 MeV T/2 0.8067 s

1. The ion is spinless, and therefore decays at rest are isotropic.

2. It can be produced at high rates, I.e.5E13 6He/s

3. The neutrino spectrum is known on the basis of the electron spectrum.

DATA and theory:<Ekine>=1.578 MeV<E>=1.937 MeVRMS/<E>=37%

B.M. Rustand and S.L. Ruby, Phys.Rev. 97 (1955) 991B.W. Ridley Nucl.Phys. 25 (1961) 483

Alain Blondel

Neutrino Source

Possible neutrino emitter candidate:18Ne

The same technology used in the production of 6He is limitedin the 18Ne case to 1012 ions/s.Dedicated R&D should increase this figure. Use this intensity as reference.

Issues: MgO less refractory,heat dissipation

Alain Blondel

Beta Beam (P. Zucchelli)

PS

SPS

Decay

RingISOL

target

SPL

ACCUMULATORPSPS

SPS

Decay

RingISOL

target

SPL

ACCUMULATOR

M. Lindroos et al.

Alain Blondel

Combination of beta beam with low energy super beamUnique to CERN:

need few 100 GeV accelerator (PS + SPS will do!)experience in radioactive beams at ISOLDE

many unknowns: what is the duty factor that can be achieved? (needs < 10 -

3 )

combines CP and T violation tests

e (+) (T) e (+)

(CP)

e (-) (T) e (-)

Can this work???? theoretical studies now on beta beam + SPL target and horn R&D design study together with EURISOL

Alain Blondel

Superbeam & Beta Beam cost estimates

Educated guess on possible costs USD/CHF 1.60UNO 960 MCHFSUPERBEAM LINE 100 MCHFSPL 300 MCHFPS UPGR. 100 MCHFSOURCE (EURISOL), STORAGE RING 100 MCHFSPS 5 MCHFDECAY RING CIVIL ENG. 400 MCHFDECAY RING OPTICS 100 MCHF

TOTAL (MCHF) 2065 MCHFTOTAL (MUSD) 1291 MUSD

INCREMENTAL COST (MCHF) 705 MCHFINCREMENTAL COST (MUSD) 441 MUSD