1. Linear Accelerator Laboratory – Orsay – France
SPLFréjus
J-E Campagne
Linear Accelerator Laboratory – Orsay – France
Thanks: A. Cazes, M. Mezzetto, Th. Schwetz
and the GLoBES team
and AM Lombardi, R. Garoby

2. A possible schema CERN SPL LSM-Fréjus 130km Near detector
TRE
CERN SPL
LSM-Fréjus
Near detector
130km
Related talks
Machines
R. Garoby & M. Lindroos
+ BetaBeam: see M. Mezzetto
+ ATM n: see Th. Schwetz

3. SPL block diagram (CDR 1)
Characteristics (Conceptual Design Report 1):
are “optimized” for a neutrino factory
assume the use of LEP cavities & klystrons up to the highest energy
2.2GeV

4. Gradients at 700 MHz Last test performed in CryHoLab (July 04):
from Stephane Chel, HIPPI04, Frankfurt, sep04
Last test performed in CryHoLab (July 04):
5-cells 700 MHz ß=0.65 Nb cavity A5-01
from CEA/Saclay and IPN-Orsay
LEP cavities may have worked 350MHz & 3.6MV/m effective gradient
NuFact Note 040

5. New optimization questioned @ MMW04*
Particle production
Horn design optimisation
Decay tunnel parameter optimisation
Flux computation at Fréjus
q13 and dCP sensitivity. p p n
LAL – submitted to EPJC
*: Multi MegaWatt Workshop at CERN May 04

6. Particle production Proton beam : Target :
Pencil like
Ek=2.2GeV, 3.5GeV…
Target :
30cm long cylinder, 15mm in Liq. Hg
FLUKA
Normalized to a power of 4MW:
GeV
GeV

7. SuperBeam vs nFact Optics
px/pz x
20 mrad
2 m
Super Beam
Spot 130km
Decay tunnel size
px/pz x
½ rad
30cm
nFact
Decay channel solenoids
Aperture and B strength
Thanks S. Gilardoni

8. at the exit of the target
p (2.2GeV) p+ Hg
Pion production
nFact SB
at the exit of the target
Horn optimisation by S. Gilardoni
This new optimisation
2 105 pot
Rule of thumb: Ep/3~ En (GeV)  2.L(km)

9. Kaon production? at 2.2GeV : at 3.5GeV : at 4.5GeV : 0.26 p+/s
see BENE meeting 11/09/03
Ep(GeV) p+ p- K+ K- K0
Not physical dip !!!
Not Used…
3.5
2.2
For pot
at 2.2GeV :
0.26 p+/s
K+/s
at 3.5GeV :
0.29 p+/s
K+/s
at 4.5GeV :
0.32 p+/s
K+/s

10. Conductor thickness : 3mm
Horn design parameter
140 cm
220 cm
80 cm
Conductor thickness : 3mm
horn : 300kAmps
reflector : 600kAmps
Challenging!!!
Drawing from the horn built at CERN
Optimized for Super Beam
HORN
inner radius
3.4cm
neck length
40cm
outer radius
20.5cm
total length
140cm
REFLECTOR
220cm
En~300MeV
Ep~800MeV
+ or - focusing
Using Geant 3.2.1
NuFact-Note 138

11. Decay Tunnel Parameters
Length
modify purity
L=10m, 20m, 40m and 60m have been tested.
10m40m
nm , nm + 50% to 70%
ne , ne + 50% to 100%
40m60m
nm , nm + 5%
ne , ne + 20%
40m seems better
Radius
modify acceptance
R=1m, 1.5m and 2m have been Tested
1m 2m (L=40)
nm , nm +50%
ne , ne +50% to 70%
Larger is better (2m)…
This results have been checked on sensitivity to q13 and dCP

12. Fluxes comparison @ 130km ~95 nmCC/kT/yr*
<En> ~ 300 MeV, /100m2/yr
3.5GeV SPL optimum
<En> ~ 245 MeV, /100m2/yr
2.2GeV SPL optimum
<En> ~ 275 MeV, /100m2/yr
Old nFact optimum
*: Lipari x-sect. (see later)

13. nm ne ne nm Flux @ 130km: + focusing p+ m+ x1/140
x1/140
x1/17
x1/3000 nm ne p+ m+
3.5GeV Kinetic p beam
~800MeVp focusing
40m decay tunnel length
2m decay tunnel radius
ne
nm
~1/2 m-
~1/2 K0e3 p-

14. The X-sections
nm SPL
---: Lipari et al.
on H20
bB is an ideal tool to measure these cross-sections and a 2% systematic error on both signal and background are used.

15. Analysis: GLoBES + M. Mezzetto’s parameterization file
440kT x 5yrs: 2,2 Mt.yrs (+)
nmne (Sig)
q13 = 1°
q13 = 3°
sin22q13= 0.05 33
(d = p/2)
330
2200
3670
(d = 0°)
nmne (Bkg)
1500
ne ne CC
p0 from NC
nm nm CC
(m missId)
ne ne CC
Frac. of Bkg
90% 6% 3% 1%
Reduction Factor
0.707(1060)
(90)
(45)
0.677(15)
nmnm (Sig)
64950
64414
nmnm (Bkg)
3 ( nmnm CC)
sin22q12=0.82, q23=p/4, Dm221= eV2, Dm231= eV2
Reduction factor and efficiencies taken from SK simulation (D. Casper) and a tight cut for e/m misId. (cf. hep-ph/ )

16. 440kT x 8yrs: 3,5 Mt.yrs (-) nmne (Sig) q13 = 1° q13 = 3°
sin22q13= 0.001
q13 = 3°
sin22q13= 0.01
sin22q13= 0.05
110
(d = p/2)
390
1300
1140
(d = 0°)
nmne (Bkg)
490
ne ne CC
ne  ne CC
p0 from NC
nm nm CC
(m missId)
Frac. of Bkg
45%
35%
18% 2%
Reduction Factor
0.677(220)
0.707(170)
(90)
(10)
nmnm (Sig)
19760
19590
nmnm (Bkg)
1 ( nmnm CC)
sin22q12=0.82, q23=p/4, Dm221= eV2, Dm231= eV2

17. Some physics performances
440kT water Č, 4MW SPL, opti. Fluxes
dCP=0
preliminary
90%CL
New Opt.
Old Opt.
5yrs (+)
True values: (Dm23, sin22q13)
sin22q12=0.82, q23=p/4, Dm221= eV2
5% external precision on q12 and Dm221 and use SPL disappearance channel and spectrum analysis*
2% syst. on signal & bkg
Sin22q13(90%CL) = (0.7°)
sizeable improvement
*: 5 bins [0.08,1.08] GeV
(2(2dof)=4.6 or 11.83)

18. Some physics performances
True values: dCP=0, q13=0, sin22q12=0.82, q23=p/4, Dm221= , Dm231=
5% external precision on q12 and Dm221 and use SPL disappearance channel
2yrs (+)
8yrs (-)
preliminary
T2K-I
Rate only
Spectrum analysis (prelim.)
90%CL (2(2dof)=4.6)
5yrs (+)
Old SPL
x10
2yrs (+)
8yrs (-)
preliminary
Improve T2K-I
2% syst. on signal & bkg

19. Some physics performances
CP 3s
2yrs (+)
8yrs (-)
preliminary
Old Opti.
New Opti.
True values (dCP,q)
Tests dCP=0 and dCP=p
sin22q12=0.82, q23=p/4,
Dm221= , Dm231=
5% external precision on q12 and Dm221
use SPL disappearance channel
2% syst on signal & bkg
Use glbChiDelta and 2 (1dof)=9

20. Evolution of the performances
2yrs (+), 8 yrs (-)
0.02
0.04
0.06
sin22q13 -1
-0.5
0.5
d/p
“nFact opt.”
“ 3.5 GeV opt.”
true
Wrong q23
Wrong hierarchy
Wrong
hierarchy and q23
90%CL
Solid: SPL+ATM
Dashed: SPL only
NNN05
New Prelim.
True values: dCP/p =-0.85, sin22q13=0.03, sin2q23=0.4,
5% external precison on Dm221= , Dm231= , q23
cf. Th. Schwetz

21. CDR2 block diagrams CERN proton complex 1-2GeV Eurisol, bB 2-3.5GeV
SuperB, NuFact

22. Global planning (R.G courtesy)
RF tests in SM 18 of prototype structures* for Linac4
3 MeV test place ready
Linac4 approval
SPL approval
CDR 2

23. Summary Thank you Higher proton energy & SB Horn specific
new baseline: 3.5GeV/2m/40m
q13 sensitivity:
sensitivity to q13 = 0.7° (5yrs +): gain +25% wrt old result
down to q13 = 1.4° with the 10yrs mixed scenario independently of dCP
Improve T2K-I by a factor 10 at dCP = 0 (5yrs +)
Can discover CP violation
Can solve ambiguities alone and result is improved thanks to ATMn (Th. Schwetz ‘s talk)
Complementary to BetaBeam to cross check the background and improve dCP sensitivity (M. Mezzetto’s talk)
Thank you

24. END

25. q13 and dCP Sensitivity computation
Use GLoBES v and M. Mezzetto SPL.glb file
detector:
Water Cerenkov
440 kt
at Fréjus (130 km from CERN)
Run:
5 years p+
1 year p+ + 4 years p-
2 years p+ + 8 years p-
Computed with dCP=0 (standard benchmark) and q13 = 0
other parameters…
Dm23 = eV2
Dm12 = eV2
Same
duration
Same statistics
sin22q23 = 1.0
sin22q12 = 0.82

26. nm ne nm ne Flux @ 130km: - focusing 1/3 m+ 1/3 K0e3 1/3 K+e3 p+
3.5GeV Kinetic p beam
~800MeVp focusing
40m decay tunnel length
2m decay tunnel radius
x1/1300
x1/10
x1/200 p- m-
nm
ne

27. 5 years positive focusing
Energy comparison
Focusing comparison
dCP = 0
10-3
sin22q13
Dm223 (eV2)
En~260MeV
dCP = 0
10-3
sin22q13
Dm223 (eV2)
Best
sin22q13 >
Ek = 4.5GeV
En=300MeV
tunnel : 40m long
2m radius

28. positive focusing vs 10 years mixed scenario.
Energy comparison
Focusing comparison
300MeV
4.5GeV
3.5GeV
260MeV
2y+
8y-
5y+ 50
2.2GeV
3.5GeV
4.5GeV
8GeV
-50
-50
5y+
2y+
8y-
-100
-100
-150
-150
10-4
10-3
10-4
10-3
10-4
10-3
10-4
10-3
Best
sin22q13 >
Ek = 3.5GeV
En=300MeV
tunnel : 40m long
2m radius
90%CL

29. General comparison.
5y mixed focusing
10y mixed focusing
5y positive focusing
for 10 years in mixed focusing, sensitivity around q13~1°
Clear complementarily between positive scenario and bbeam (dCP>0)

30. Neutrino Flux 100km away p+ focusing evts/100m2/y Ek=3.5GeV En ~300MeV
L = 40m,R=2m
Neutrino Flux 100km away
p+ focusing
from p and m
from K0
from K
Ekine (GeV)
evts/100m2/y

31. Discrepancies reduced in the beam line
MARS vs FLUKA
At the entrance of the SB decay tunnel (after the horn focusing)
R = 1m
No angular cut
Discrepancies reduced in the beam line
A. Cazes thesis