2. 24 Aprile 2003DPNC Simone Gilardoni Introduction to the Neutrino Factory Simone Gilardoni DPNC - Université de Genève CERN - AB/ABP Division

3. 24 Aprile 2003DPNC Simone Gilardoni Neutrino oscillation Observation:  into another of different flavour Results:NEUTRINOS HAVE MASS MASS STATES  FLAVOUR STATES Parameters: 3 masses –Two  m 2 differences Three mixing angles One delta phase

4. 24 Aprile 2003DPNC Simone Gilardoni Neutrino Oscillations Mixing described by For 3-flavour eigenstates U is Maki-Nakagawa-Sakata (MNS): 6 parameters: 3 mixing angles - θ 23,θ 12 and θ 13 CP-violation angle - δ 2 mass differences - Δm 2 23 and Δm 2 12 Transition probability:

5. 24 Aprile 2003DPNC Simone Gilardoni Three family oscillation Atmospheric Neutrinos Solar Neutrinos Phase  CP Super-K atm. P(    ) Maximal mixing  m 2  3 10 -3 eV 2 L/E = 1 GeV/500 km SNO P( e  x ) Large Mixing (LMA) Kamland L/E  MeV/1.5 10 11 m Limit from CHOOZ Goal of next generation of neutrino-beam If  13 is zero, IMPOSSIBLE to observe CP violation

6. 24 Aprile 2003DPNC Simone Gilardoni Two friends for Nufact SNO: D 2 O detector Non- e flux in solar neutrinos Kamland: e disappearance from Nuclear Reactor LMA solution for solar neutrinos

7. 24 Aprile 2003DPNC Simone Gilardoni THE last results G.Fogli et al., PR D66, 010001- 406,(2002) The LMA solution for solar neutrinos is confirmed The L/E oscillation pattern is confirmed

8. 24 Aprile 2003DPNC Simone Gilardoni B.Kaiser

9. 24 Aprile 2003DPNC Simone Gilardoni Road Map Experiments to look for  13 –Look for   e in  beam (ICARUS, MINOS) –Off-axis beam (JHF-SK, off axis NUMI) –Low energy SuperBeams Experiments to look for CP/T violation or for  13 (if too small) –Beta-beams (combined with SuperBeam) –Neutrino Factory

10. 24 Aprile 2003DPNC Simone Gilardoni Sensitivity of Nufact 0.1 o 1o1o 2.5 o 5o5o 13 o

11. 24 Aprile 2003DPNC Simone Gilardoni JHF ready in 2007 Construction 2001 ～ 2006 (approved) JAERI@Tokai-mura (60km N.E. of KEK) (0.77MW) Super Conducting magnet for beam line Near detectors @280m and @~2km 10 21 POT(130day)≡ “1 year”

12. 24 Aprile 2003DPNC Simone Gilardoni Far Detectors 48m × 50m ×500m, Total mass = 1 Mton 1 st Phase (2007~, ≥5yrs) Super-Kamiokande(22.5kt) 2 nd Phase (201x~?) Hyper-Kamiokande(~1Mt)

13. 24 Aprile 2003DPNC Simone Gilardoni Proposal for a CERN - Super Beam

14. 24 Aprile 2003DPNC Simone Gilardoni Nufact CERN layout

15. 24 Aprile 2003DPNC Simone Gilardoni Nufact FAQ Why neutrinos from stored muons: –Pure , e beam –Switching the helicity by switching the muon sign –Hope for a muon collider (may be… one day…) Why high energy ? –High cross section neutrino interaction –Small E/L (50GeV/3500 km) Why so many neutrinos? Is there someone that can do better before? –See the roadmap

16. 24 Aprile 2003DPNC Simone Gilardoni Beam Composition Nufact BeamWANF Beam The scales are different !

17. 24 Aprile 2003DPNC Simone Gilardoni Energy and flux specs NuFact near detector 10 20  decay/year 4.0 10 6 CC evt. 1.7 10 6  CC evt. per kg-year Minos near detector 3.7 10 20 pot/year 2.5 10 6 CC evt. 0.6 10 6 CC evt. per ton-year Physics at far detector

18. 24 Aprile 2003DPNC Simone Gilardoni The Holy Grail: any leptonic CP violation? CP is observable IF: sin 2  12 and  m 2 12 are large (LMA) and sin 2  13 small (but not too small…) Appearance experiment: P( e   ) –P( e  e ) is T invariant  CP is conserved (CP not observable from solar or reactor neutrinos)

19. 24 Aprile 2003DPNC Simone Gilardoni Measure  13 via P( e   ) with a precision of 10 -3 or setting a limit to 10 -6 Determine via MSW the sign of  m 2 Discover and measure the CP violation in the leptonic sector (phase  P( e   )  P( e   ) Need of high energy e :    e   e +   Physics at a Nufact

20. 24 Aprile 2003DPNC Simone Gilardoni  +  e + +  + e        + Oscillation Wrong Sign muons 10 16 p/ s 3 10 20 e  yr 3 10 20   yr 0.9 10 21  yr

21. 24 Aprile 2003DPNC Simone Gilardoni High Power –LINAC @ 4 MW –Rep. Rate 50 Hz –2.27 10 14 p/pulse spaced by 22.7 nsec (44 MHz) Accumulator ring to reduce the pulse length CERN interested at least in the low energy part for the LHC upgrade and the improvement of CNGS Superconducting Proton Linac SPL @ 2.2 GeV

22. 24 Aprile 2003DPNC Simone Gilardoni Accumulator and Compressor Accumulator –Macrobunch with internal 23 ns structure (44 MHz) MUON BUNCHES KEEP THIS STRUCTURE –Macrobunch Rep. rate: 20 ms (50 Hz) Compressor –Microbunch length reduction to from 3.5 ns to 1 ns –Time spread due to Pion decay  1 ns

23. 24 Aprile 2003DPNC Simone Gilardoni PDAC time scheme 44 MHz structure 50 Hz

24. 24 Aprile 2003DPNC Simone Gilardoni Proposed site Old ISR tunnel, site of accumulator + bunch compressor Radius = 50 m

25. 24 Aprile 2003DPNC Simone Gilardoni Target Nufact Target: –Mercury: Z = 80  short target Liquid  easy to replace (v //  20 m/s) –Dimensions: L  30 cm, R  1 cm 40000  4 MW =  4 MW of proton into a pint of beer

26. 24 Aprile 2003DPNC Simone Gilardoni Target experiment Experiments @BNL and @CERN Measurements of Hg explosion speed –Speed of protons >> Speed of sound Maximum v   20 m/s v //  3 m/s Protons 1 cm

27. 24 Aprile 2003DPNC Simone Gilardoni Jet test a BNL E-951 Event #11 25 th April 2001 P-bunch:2.7  10 12 ppb 100 ns t o = ~ 0.45 ms Hg- jet :diameter 1.2 cm jet-velocity 2.5 m/s perp. velocity ~ 5 m/s Picture timing [ms] 0.00 0.75 4.50 13.00 K. Mc Donald, H. Kirk, A. Fabich Protons

28. 24 Aprile 2003DPNC Simone Gilardoni The Harp experiment Hadron production cross section measurement

29. 24 Aprile 2003DPNC Simone Gilardoni Top viewSide view Front view Protons 12 GeV Be target

30. 24 Aprile 2003DPNC Simone Gilardoni Magnetic horn Protons Current of 300 kA To decay channel  Hg Target B  1/R B = 0

31. 24 Aprile 2003DPNC Simone Gilardoni First piece of Nufact Merci à l’ atelier du CERN

32. 24 Aprile 2003DPNC Simone Gilardoni Time (arb.) Decay channel Energy (GeV) Solenoid B=1.8 T, L=30 m  “Life Time”  18 m @ p=400 MeV/c Geometry Energy spread reduction needed   Huge Energy spread –Huge velocity spread –LEP  E /E  10 -3 –NF  E /E  2 Debunching Beam type –  –E-t correlation 30 m

33. 24 Aprile 2003DPNC Simone Gilardoni Nufact CERN layout

34. 24 Aprile 2003DPNC Simone Gilardoni What is a “Phase Rotation”? Aim: Reducing the energy spread of a non-relativistic beam How: series of RF cavities that - accelerates low-energy particles - decelerates high-energy particles

35. 24 Aprile 2003DPNC Simone Gilardoni Phase rotation example 100  E  300 MeV 30 RF cavities:  2 MV/m  44 MHz  L = 1 m  B = 1.8 T E = 200  50 MeV time 300 200 100 MeV

36. 24 Aprile 2003DPNC Simone Gilardoni 88 MHz cavity prototype

37. 24 Aprile 2003DPNC Simone Gilardoni Cooling: the problem (transverse phase space) Accelerato Accelerator acceptance R  10 cm, x’  0.05 rad rescaled @ 200 MeV  and  after focusing Problem:  Beam pipe radius of storage ring P  or x’ and x reduction needed: COOLING

38. 24 Aprile 2003DPNC Simone Gilardoni Ionization Cooling : the principle H2H2 rf Liquid H 2 : dE/dx RF restores only P // : E constant Beam sol

39. 24 Aprile 2003DPNC Simone Gilardoni 2) Focusing : a) Needed when x’ reduction comparable with multiple scattering b) same rotation center for the spiral motion. (Rematching) Cooling : the channel 1) Cooling I : x’ reduction3) Cooling II : x’ reduction Heating term ‘ H 2 has X 0 = 8.9 m Cooling works best with high x’

40. 24 Aprile 2003DPNC Simone Gilardoni Cooling: the results Results: phase space density increased by 16 (Cooling rate for MICE: 16%) IN OUT

41. 24 Aprile 2003DPNC Simone Gilardoni Channel engineering design

42. 24 Aprile 2003DPNC Simone Gilardoni MICE: Muon Ionisation Cooling Experiment Proposal to be submitted to RAL before end of the year

43. 24 Aprile 2003DPNC Simone Gilardoni Accelerator and Particle physics together TPG Tracker SciFi Tracker Example of cooling

44. 24 Aprile 2003DPNC Simone Gilardoni Mice roadmap (at RAL?)  - STEP I: 2004 STEP II: summer 2005 STEP III: winter 2006 STEP IV: spring 2006 STEP V: fall 2006 STEP VI: 2007

45. 24 Aprile 2003DPNC Simone Gilardoni Nufact CERN layout

46. 24 Aprile 2003DPNC Simone Gilardoni Storage ring Two straight sections pointing to two detectors Two possible shapes –triangle –bow tie Lattice design for beam divergence x’   beam divergence dominated by   decay   =m  /p  = 2mrad (@ 50 GeV)  25% useful decays per direction

47. 24 Aprile 2003DPNC Simone Gilardoni Technical problems 14  Could you imagine a screw driver falling down from here?

48. 24 Aprile 2003DPNC Simone Gilardoni Nufact CERN layout

49. 24 Aprile 2003DPNC Simone Gilardoni Around Europe... First possible location: Gran Sasso 732 km Second location: 3500 km away best Candidates: Svalbards (Norway) Gran Canaria (Spain)

50. 24 Aprile 2003DPNC Simone Gilardoni Where do you prefer to take shifts ?

51. 24 Aprile 2003DPNC Simone Gilardoni Why two locations? From P. Hernandez Fit of  13 and  a the same time No sensitivity at 732 km Better to combine with 2810 km

52. 24 Aprile 2003DPNC Simone Gilardoni But not too far: no CP sensitivity L = 7332 km From P. Hernandez

53. 24 Aprile 2003DPNC Simone Gilardoni The world as playground

54. 24 Aprile 2003DPNC Simone Gilardoni Far Detector Iron calorimeter Magnetized –Charge discrimination –B = 1 T R = 10 m, L = 20 m Fiducial mass = 40 kT Baseline 3500 Km 732 Km3.5 x 10 7 1.2 x 10 6 5.9 x 10 7 2.4 x 10 6 1.1 x 10 5 1.0 x 10 5  CC e CC  signal Events for 1 year

55. 24 Aprile 2003DPNC Simone Gilardoni The neutrino factory golden-measurement is the CP violation. Super-Beam+Beta-Beam are competitive in various ways, including T violation! General Considerations  = 90 deg 99%C.L. Curves (M. Mezzetto, NNN02)

56. 24 Aprile 2003DPNC Simone Gilardoni Last question: about financing? For the time being our situation is not so good…. BUT….. Some ideas are developing…

57. 24 Aprile 2003DPNC Simone Gilardoni Reserve ……………………………………

58. 24 Aprile 2003DPNC Simone Gilardoni Total flux of 8 B neutrinos

59. 24 Aprile 2003DPNC Simone Gilardoni SNO detector 1000 ton of D 2 0 12 m diam. 9456 PMTs Aim: measuring non e neutrinos in a pure solar e beam How? Three possible neutrino reaction in heavy water:

60. 24 Aprile 2003DPNC Simone Gilardoni SNO: the Puzzle solution LMA (Large Mixing Angle) is the preferred solution SNO Day and Night Energy Spectra Alone Combining All Experimental and Solar Model information

61. 24 Aprile 2003DPNC Simone Gilardoni Usual attitude for LSND

62. 24 Aprile 2003DPNC Simone Gilardoni Summary of experimental results Good news: –LMA solar solution still in good shape –To be confirmed by KAMLAND SNO data taking going on Super-K rebuilt in short time

63. 24 Aprile 2003DPNC Simone Gilardoni sin 2 2  13 * Designed for  appearance <0.013  JHF-SK <0.028<0.040 ?  Low energy CNGS <0.033<0.039<0.056  CNGSx1.5* <0.039<0.047<0.067  CNGS* <0.042<0.049<0.06<0.085  MINOS <0.14 CHOOZ 200920082007200620052004 P. Migliozzi Indication of time-line

64. 24 Aprile 2003DPNC Simone Gilardoni The BETA-BEAM 1. Produce a Radioactive Ion with a short beta-decay lifetime 2. Accelerate the ion in a conventional way (PS) to “high” energy 3. Store the ion in a decay ring with straight sections. 4. It will decay. e ( e ) will be produced. - SINGLE flavour - Known spectrum - Known intensity - Focussed - Low energy - “Better” Beam of e ( e ) The “quality factor” QF=  /E 0 is bigger than in a conventional neutrino factory. In addition, ion production and collection is easier. Then, 500000X more time to accelerate. Muons:  ~500 E 0 ~34 MeV QF~15 6 He Beta-:  ~150 E 0 ~1.9 MeV QF~79 18 Ne Beta+:  ~250 E 0 ~1.86 MeV QF~135

65. 24 Aprile 2003DPNC Simone Gilardoni The Acceleration principle ISOL Target and ECR LinacCyclotronStorage Ring PSSPS 2500 m R=300 m Decay ring/Buncher Bunch rotation is the crucial issue for atmospheric background control! Studies are made on EXISTING CERN machines. Why? Much more detailed knowledge exists, the best way to identify possible problems and limitations.

66. 24 Aprile 2003DPNC Simone Gilardoni channel at neutrino factory High energy neutrinos at NuFact allow observation of  e   (wrong sign muons with missing energy and P  ). UNIQUE Liquid Argon or OPERA-like detector at 3000 km. Since the sin  dependence has opposite sign with the wrong sign muons, this solves ambiguities that will invariably appear if only wrong sign muons are used. ambiguities with only wrong sign muons (3500 km) equal event number curves muon vs taus associating taus to muons (no efficencies, but only OPERA mass) studies on-going A. Donini et al

67. 24 Aprile 2003DPNC Simone Gilardoni Why so far? Earth diameter: Vertical storage ring?

68. 24 Aprile 2003DPNC Simone Gilardoni Degeneracies Degeneracy: 2 or more parameter sets fit the same data Three types, all of which can effect measurement of  &  13 :  13 =8 o,  =-90 o, 0 o, 90 o, 180 o (1) (2) (3) (1) 

69. 24 Aprile 2003DPNC Simone Gilardoni Degeneracies  13 large NB depends on L/E  possible solutions Two baselines and E-dependence at NF NF + SB combination Two off-axis detectors e   as well as e   Mena Huber/Mena Whisnant Meloni

70. 24 Aprile 2003DPNC Simone Gilardoni Degeneracies Mena NuFact at 2810km + SB at 130KM NuFact at 732km + SB at 130KM large small

71. 24 Aprile 2003DPNC Simone Gilardoni e appearance in JHF-Kamioka (phase 1)  e 00 1.8 events 9.3 events 11.1 events 123.2 events @ sin 2 2  13 =0.1,  m 2 =3×10 -3 eV 2 Backgrounds Signal (5 years running)

72. 24 Aprile 2003DPNC Simone Gilardoni Europe: SPL  Frejus Geneve Italy 130km 40kt  400kt CERN SPL @ CERN 2.2GeV, 50Hz, 2.3x10 14 p /pulse  4MW Now under R&D phase

73. 24 Aprile 2003DPNC Simone Gilardoni SPL neutrino beam

74. 24 Aprile 2003DPNC Simone Gilardoni CP  and  13 40 kt Detector 400 kt Detector Running time: 10 y antineutrinos 2 y neutrinos