Presentation on theme: "Alain Blondel Three family oscillations Low energy Super-beam: JHF CERN-SPL … and beta-beam Neutrino Factory Neutrino Factory R&D and new developments:"— Presentation transcript:
Alain Blondel Three family oscillations Low energy Super-beam: JHF CERN-SPL … and beta-beam Neutrino Factory Neutrino Factory R&D and new developments: EMCOG, MICE, ring cooler BENE and design studies Conclusions Future neutrino experiments The road-map… and a few itineraries
Alain Blondel 1.We know that there are three families of active, light neutrinos (LEP) 2. Solar neutrino oscillations are established (Homestake+Gallium+Kam+SK+SNO+KamLAND) 3.Atmospheric neutrino ( ) oscillations are established (IMB+Kam+SK+Macro+Sudan) 4.At that frequency, electron neutrino oscillations are small (CHOOZ) This allows a consistent picture with 3-family oscillations ~30 0 m 12 2 ~ eV 2 ~45 0 m 23 2 ~ eV 2 ~ 10 0 with several unknown parameters mass hierarchy Where are we? *)to set the scale: CP violation in quarks was discovered in 1964 and there is still an important program (K0pi0, B-factories, Neutron EDM, BTeV, LHCb..) to go on for 10 years…i.e. a total of ~50 yrs. and we have not discovered leptonic CP yet! 5. There is indication of possible higher frequency oscillation (LSND) to be confirmed (miniBooNe) This is not consistent with three families of neutrinos oscillating, and is not supported (nor is it completely contradicted) by other experiments. (Case of an unlikely scenario which hangs on only one not-so-convincing experimental result) If confirmed, this would be even more exciting See Barger et al PRD Where do we go? leptonic CP & T violations => an exciting experimental program for at least 25 years *)
Alain Blondel The neutrino mixing matrix: 3 angles and a phase Unknown or poorly known even after approved program: 13, phase , sign of m 13 OR? m 2 23 = eV 2 m 2 12 = eV 2 23 (atmospheric) = 45 0, 12 (solar) = 30 0, 13 (Chooz) < m 2 12 = eV 2 m 2 23 = eV 2
Alain Blondel Consequences of 3 Family oscillation: I There will be ↔ e and ↔ e oscillation at L atm P ( ↔ e ) max =~ ½ sin 2 2 13 +… (small) II There will be CP or T violation CP: P ( ↔ e ) ≠ P ( ↔ e T : P ( ↔ e ) ≠ P ( e ↔ III we do not know if the neutrino which contains more e is the lightest one (natural?) or not. Oscillation maximum 1.27 m 2 L / E = /2 Atmospheric m 2 = eV 2 L = GeV Solar m 2 = eV 2 L = 1 GeV
Alain Blondel = A CP sin solar term… sin sin ( m 2 12 L/4E) sin … need large values of sin m 2 12 (LMA) but *not* large sin 2 … need APPEARANCE … P( e e ) is time reversal symmetric (reactors or sun are out) … can be large (30%) for suppressed channel (one small angle vs two large) at wavelength at which ‘solar’ = ‘atmospheric’ and for e , … asymmetry is opposite for e and e P( e ) - P( e ) P( e ) + P( e ) P( e ) = ¦A¦ 2 +¦S¦ A S sin P( e ) = ¦A¦ 2 +¦S¦ A S sin
Alain Blondel LEPTONIC T, CP VIOLATION The baryon asymmetry in the Universe… requires CP or T violation. That of the quarks is not enough! Boris Kayser This leptonic asymmetry would in turn generate baryon asymmetry. (energies typical of the particles that would be exchanged in Baryon decay GeV or so) NB this is CP asymmetry for the Heavy Majorana Neutrinos 1. we don’t know if neutrinos are Majorana particles 2. The CP phases that enter are those of the heavy neutrinos, not the light ones. Nevertheless: leptonic CP violation may be the reason why we exist… lets look for it!
Alain Blondel Road Map Experiments to find : 1. search for e in conventional beam (ICARUS, MINOS) limitations: NC background, intrinsic e component in beam 2. Off-axis beam (JHF-SK, off axis NUMI, off axis CNGS) or 3. Low Energy Superbeam Precision experiments to find CP violation -- or to search further if is too small 1. Neutrino factory with muon storage ring 2. beta-beam 6 He ++ Li +++ e e fraction thereof will exist. e + e and e - e
Alain Blondel Where will this get us… comparison of reach in the oscillations right to left: present limit from the CHOOZ experiment, expected sensitivity from the MINOS experiment, 0.75 MW JHF to super Kamiokande with an off-axis narrow-band beam, Superbeam: 4 MW CERN-SPL to a 400 kton water Cerenkov in Fréjus from a Neutrino Factory with 40 kton large magnetic detector. INCLUDING SYSTEMATICS sin 2 Mezzetto
Alain Blondel JHF Super-Kamiokande z295 km baseline zJ-PARC approved zneutrino beam under discussion but set as first priority by international committee zProposal to be submitted early 2004 zSuper-Kamiokande: y22.5 kton fiducial yExcellent e/ ID yAdditional 0 /e ID (for E ~ 500 MeV- 1 GeV) zMatter effects small zneed near detector! zEuropean collaboration forming (mailing list: UK(5)-Italy(5)- Saclay-Gva-ETHZ- Spain(2)) This experiment is at the right ratio of Energy to distance L max = 300 km at 0.6 GeV
Alain Blondel Detector Phase I: the Super Kamiokande Detector
Alain Blondel /e Background Rejection e/ separation directly related to granularity of coverage. Limit is around (mu decay in flight) SKII coverage OKOK, less maybe possible
Alain Blondel p 140 m0 m280 m2 km295 km Problem with water Cerenkov: not very sensitive to details of interactions. Either 280 m or 2 km would be good locations for a very fine grained neutrino detector Planned: a scintillating fiber/water calorimeter. Liquid argon TPC would be a very good (better) candidate! Event numbers: near/SK = m(near[tons]) / (300/2) 2 = m(near[tons]) => Need tons fiducial or so The J-PARC- Beamline 1.5km 295km Neutrino spectra at diff. dist 280m
Alain Blondel Under discussion: Possible Swiss contributions to JPARC- a)Beam design and control: studies of high power horn in GVA – in collab. with CERN and LAL Orsay expertise in hadronic production b) A liquid Argon near detector? Generated interest in JHF-Europe! ETHZ leads the show. What would be the envelope?
Alain Blondel Schematic drawing of Hyper-Kamiokande 1 Mton (fiducial) volume: Total Length 400m (8 Compartments) Super-K 40m Other major goal: improve proton decay reach Supernovae until Andromedes, etc…
Alain Blondel Motivations to go beyond this… 1.Intrinsic limits of conventional neutrino beams (intensity, purity, only , low energy ) 2.Go back to Europe and try to establish a possible CERN-based program on the long run Superconducting Proton Linac SPL Superbeam Neutrino factory The ultimate tool for neutrino oscillations Beta beam Very large underground lab Water Cerenkov, L.Arg The common source: SPL EURISOL High intensity Low energy muon beams SPL physics workshhop: June 2004 CERN SPC Cogne meeting sept.2004
Alain Blondel -- Neutrino Factory -- CERN layout e + e _ interacts giving oscillates e interacts giving WRONG SIGN MUON p/ s s = yr e yr yr yr
Alain Blondel 300 MeV Neutrinos small contamination from e (no K at 2 GeV!) A large underground water Cerenkov (400 kton) UNO/HyperK or/and a large L.Arg detector. also : proton decay search, supernovae events solar and atmospheric neutrinos. Performance similar to J-PARC II There is a window of opportunity for digging the cavern stating in 2008 (safety tunnel in Frejus) Possible step 0: Neutrino SUPERBEAM Fréjus underground lab.
Alain Blondel Europe: SPL Frejus Geneve Italy 130km 40kt 400kt CERN CERN 2.2GeV, 50Hz, 2.3x10 14 p /pulse 4MW Now under R&D phase
Alain Blondel Neutrino Factory studies and R&D USA, Europe, Japan have each their scheme. Only one has been costed, US study II: Neutrino Factory CAN be done…..but it is too expensive as is. Aim: ascertain challenges can be met + cut cost in half. + detector: MINOS * 10 = about 300 M€ or M$
Alain Blondel EMCOG (European Muon Concertation and Oversight Group) FIRST SET OF BASIC GOALS The long-term goal is to have a Conceptual Design Report for a European Neutrino Factory Complex by the time of JHF & LHC start-up, so that, by that date, this would be a valid option for the future of CERN. An earlier construction for the proton driver (SPL + accumulator & compressor rings) is conceivable and, of course, highly desirable. The SPL and targetry and horn R&D have therefore to be given the highest priority. Cooling is on the critical path for the neutrino factory itself; there is a consensus that a cooling experiment is a necessity. The emphasis should be the definition of practical experimental projects with a duration of 2-5 years. Such projects can be seen in the following four areas:
Alain Blondel 1.High intensity proton driver. Activities on the front end are ongoing in many laboratories in Europe, in particular at CERN, CEA, IN2P3, INFN and GSI. Progressive installation of a high intensity injector and of a linear accelerator up to 120 MeV at CERN (R. Garoby et al) would have immediate rewards in the increase of intensity for the CERN fixed target program and for LHC operation. This (HIPPI) has received funding from EU! 2. Target studies problem at 4 MW!!. This experimental program is underway with liquid metal jet studies. Goal: explore synergies among the following parties involved: CERN, Lausanne, Megapie at PSI, EURISOL, etc… Experiment at CERN under consideration by the collaboration. 3. Horn studies. Problem at 50 Hz and 4 MW A first horn prototype has been built and pulsed at low intensity. Mechanical properties measured (S. Gilardoni’s thesis, GVA) 5 year program to reach high intensity, high rep rate pulsing, and study the radiation resistance of horns. Optimisation of horn shape. IN2P3 Orsay has become leading house for this. Collaborations to be sought with Saclay, PSI (for material research and fatigue under high stress in radiation environment) 4.Muon Ionization Cooling Never done! A collaboration towards and International cooling experiment MICE has been established with the muon collaboration in United States and Japanese groups. There is a large interest from European groups in this experiment. Following the submission of a letter of Intent to PSI and RAL, the collaboration has prepared a full proposal at RAL. Proposal has been strongly encouraged and large UK funding secured (10M£). PSI offers a solenoid for the muon beam line CERN, which as already made large initial contributions in the concept of the experiment, has earmarked some very precious hardware that could be recuperated.
Alain Blondel MUON Yield without and with Cooling What muon cooling buys exact gain depends on relative amont of phase rotation (monochromatization vs cooling trade off) cooling of minimum ionizing muons has never been realized in practice involves RF cavities, Liquid Hydrogen absorbers, all in magnetic field designs similar in EU and US Nufact concepts
Alain Blondel principle: this will surely work..! reality (simplified) ….maybe… IONIZATION COOLING Difficulty: Wide aperture -> expensive. Affordable prototype of cooling section only cools beam by 10%, while standard emittance measurements barely achieve this precision. Solution: measure the beam particle-by-particle DARK current & RF NOISE!!? A delicate balance between energy loss and multiple scattering, & a technological challenge
Alain Blondel MICE An International Muon Ionization Cooling Experiment
Alain Blondel Incoming muon beam Diffusers 1&2 Beam PID TOF 0 Cherenkov TOF 1 Trackers 1 & 2 measurement of emittance in and out Liquid Hydrogen absorbers 1,2,3 Downstream particle ID: TOF 2 Cherenkov Calorimeter RF cavities 1RF cavities 2 Spectrometer solenoid 1 Matching coils 1&2 Focus coils 1 Spectrometer solenoid 2 Coupling Coils 1&2 Focus coils 2Focus coils 3 Matching coils 1&2 10% cooling of 200 MeV/c muons requires ~ 20 MV of RF single particle measurements => measurement precision can be as good as out / in ) = never done before either….
Alain Blondel We propose a Swiss contribution to the International Muon Ionization Cooling Experiment MICE -- part of international concerted effort -- the Swiss collaborators play an essential role in the design of the experiment and in its leadership. -- well matched to the competence of experimental particle physicists -- will lead to first experimental observation of ionization cooling detailed study of various absorbers, optics, and limits of accelerating gradient. => PSI will provide a muon beam solenoid. => Spectrometer (tracker and contribution to spectrometer solenoid) 720 kCHF => Collaborate with CERN to provide RF power source, based on equipment available at CERN (well justified geographically, maintains ties with CERN without asking CERN the impossible) Cant FORCE funds be allocated for this? Est 760 kCHF Submitted as SNF request with funding profile for 5 years. As a starting point for discussion. Total (including common funds, maintenance, travel and 2 PhD + 2 MA) 3.2 MCHF
Alain Blondel 250 microns pads connected in 3 sets of strips MICE tracker option: TPC with GEM readout. 1 st Prototype being built will take data by end october.
Design studies FP6 foresees funding for design studies of new infrastructures. Encouraged by EU in reference with the (approved) CARE. In preparation is the proposal for a European based Design study of a neutrino factory and superbeam RAL as leading house. (Peach/Edgecock) Proton driver CERN in coll. With RAL, etc., Target many interested. Still searching a leading house. (PSI not interested?) TTA at CERN under consideration. (pulsed beam important) Horn and collectors LAL orsay Cooling; MICE Acceleration, FFAG Saclay, Grenoble Storage ring and instrumentation NN. Europe alone does not have critical mass for all this. => world collaboration with USA and Japan was launched at NUFACT03 in June 2003.
Alain Blondel Conclusions Neutrino Physics is alive an attractive. We have an exciting program for many years. discovery and studies of leptonic CP violation This addresses very fundamental questions (GUTS, matter asymmetry, masses) from a completely different viewpoint than the energy frontier. 1. We should not miss the opportunity to make a coherent contribution to JPARC- 2. We must however make sure that there is a competitive long term program in Europe (and at CERN preferably) SPL is a good start and we must support it very strongly. Without target, horns etc… it would be however useless. And it makes full sense for particle physics as a driver for a neutrino factory Support neutrino factory R&D: MICE and collaborations with e.g. target experiment, etc…
Alain Blondel RESERVE
Alain Blondel Roadmap You are here You want to go there Where do we stand? Where do we go? Which way do we chose? Cheapest? Shortest? Fastest? Taking into account politics?
Alain Blondel Designing a superbeam experiment The process to be detected for superbeam experiments is appearance of e e + N -> e - X event with an electron in the final state. backgrounds: 1. e contamination in the beam from e + e e + e L e + e 2. production in Neutral Current events. solutions: 1. detector must separate electrons from muons 2. beam must be as pure and as monochromatic as possible or: 2’. avoid K production by using low energy proton source 3. stay at low energy (~< 0.6 GeV)to avoid production flux (E 2 /L 2) X cross-section (E) goes like E 3 /L 2 on first oscillation: oscillation goes like (L/E) 2 =>oscillated signal goes like E background goes as E 3 /L 2 => go far to avoid background ( => around 1 st maximum) on subsequent oscillations: flux and signal decrease, signal/noise does not improve, to be avoided unless it provides complementary information– to be demonstrated
Alain Blondel Charged current cross sections CCqe ( + n + p ) Inelastic NC 0 multi …. CCqe dominate ≲ 1GeV Inelastic dominate ≳ 1GeV Background data are old, sparce and sometimes ambiguous.
Alain Blondel T asymmetry for sin = JHFI-SK ! asymmetry is a few % and requires excellent flux normalization (neutrino fact. or off axis beam with not-too- near near detector ) ! JHFII-HK neutrino factory
Alain Blondel Detectors at near site zMuon ~140m yBehind the beam dump yFast (spill-by-spill) monitoring of beam direction/intensity zFirst Front detector “Neutrino yIntensity/direction yNeutrino interactions zSecond Front ~2km Almost same E spectrum as for SK yAbsolute neutrino spectrum yPrecise estimation of background yInvestigating possible sites 1.5km 295km Neutrino spectra at diff. dist 280m
Alain Blondel Syst. error: far/near spectrum diff. Typical OA beam(80mDV) 280m 295km K2K case (MC) FD(300m) (xL SK 2 /L FD 2 ) SK Important not only for disappearance, but also for sig/BG estimation for e search Large(~x2) effect around peak!!