Hadron Productions

1. Hadron Productions Present knowledge & Future plans M.G.Catanesi INFN –Bari Italy Nufact ’04 Osaka

2. Outline • Motivations (why hadron productions) • (Short) Historical overview • Recent and present measurements • Possible future extensions

3. Why Hadron Productions • Neutrino sources from hadron interactions • From accelerators • From cosmic rays • Design parameters of future neutrino beams influenced by target/energy choices NEW NEW

4. 1013 or more protons per spill: very difficult environment Only indirect evaluation MC dependence Layout of a “standard” neutrino beam

5. Neutrinos flux prediction • Energy, composition, geometry of the neutrino beam is determined by the development of the hadron interaction and cascade • It’s hard to make this kind of measurements in situ. Normally MC generators are used for this scope WANF CERN

6. Discrepancies between hadronic generators

7. Secondary particles production : • The task to make a reliable prediction of the neutrino flux at the experiment is difficult. • You need a precise knowledge of the relative population of the different kind of particles and energy spectrum . • To avoid one of the main source of systematic error the neutrino experiments community was always committed to measure in ancillary experiments the hadron production • In neutrino oscillation experiments the beam is (part of) the experiment  no credible result without a reliable understanding of the beam itself.

8. ne nm Geomagnetic field decay chain Proton fluxes: balloons, satellites Hadron Production • the atmospheric neutrino flux Calculations of the neutrino flux: the main incertainties comes from the Hadron production

9. primary flux decay chains Atmospheric neutrino fluxes • Primary flux is now considered to be known to better than 10% • Most of the uncertainty comes from the lack of data to construct and calibrate a reliable hadron interaction model. • Model-dependent extrapolations from the limited set of data leads to about 30% uncertainty in atmospheric fluxes •  cryogenic targets N2,O2 hadron production

10. G.Battistoni Discrepancies between hadronic generators

11. What hadron production measurement is needed in the atmospheric case ? q Ei , r A Importance in the cascade 5-100 GeV PId integrate over the full phase space Ni and O2 targets The experimental data are not adequate Harp & MIPP will cover this hole

12. Primary energy, target material and geometry, collection scheme • maximizing the p+, p-production rate /proton /GeV • knowing with high precision (<5%) the PTdistribution • CERN scenario: 2.2 GeV/c proton linac. • Phase rotation • longitudinally freeze the beam: slow down earlier particles, accelerate later ones • need good knowledge also of PL distribution Example of future projects

14. A little bit of history : CERN 1960/70

15. Historical overview • Mostly based on measurement of particle yields along beam lines • Experiments done making (smart) use of existing facilities • No experiments built on-purpose • Low (~20GeV/c) and high (~400GeV/c) primary proton momenta, forward angular region (<150mrad) • Low statistics and/or limited number of data points • J. Allaby et al., CERN-70-12 • p-nuclei (B4C, Be, Al, Cu, Pb) and p-p collisions at 19.2 GeV/c • Single arm spectrometer • G. Eichten et al., Nucl. Phys. B44(1972) 333 • p, K production in p-nuclei collisions (Be, B4C,Al, Cu, Pb targets) at 24 GeV/c • Single arm magnetic CERN-Rome spectrometer

16. Eichten et Al. based on CERN-70-12

17. Motivations and scope • Experiment’s uncertainties

18. NA20 (Atherton et al.) @ CERN-SPS • Secondary energy scan: 60,120,200,300 GeV • Overall quoted errors • Absolute rates: ~15% • Ratios: ~5% • These figures are typical of this kind of detector setup • H2 beam line in the SPS north-area

19. SPS: NA56/SPY • Most likely the most advanced study done with instrumented beam line experiments • Dedicated to WANF (CHORUS/NOMAD) (and CNGS) experiments • To address discrepancies beam spectrum, shape and composition as measured in CHORUS/NOMAD compared to MC predictions. • 450GeV/c incident protons, 7135 GeV/c secondaries (overlap with Atherton) • Exploits TOF / Cherenkov / Calorimetry

20. SPY:1996 0, ±15mrad, ± 30mrad target region spectrometer

21. SPY measurement principle • TOF + Cherenkov, cross-check with calorimetry.

22. Present • Aim at event-by-event experiments, not particle-by-particle • Modern design • Open-geometry spectrometers • Full solid angle and P.Id. • Design inherited from Heavy Ions experiments (multiplicity, correlations, pion interferometry, …) • Full momentum acceptance, scan on incident proton momenta (not only on momentum of secondaries) • High event rate • Heavy ions experiments are designed for very high track density per event, not for high rate of relatively simple events

23. E910 • BNL E910 • main goal: Strangeness production in p-A collision (comparison with A-A collisions) • Some data overlap with our needs • 6,12,18 GeV/c beam proton momenta • Be, Cu, Au targets • however • low statistics in general (this is common in heavy-ions experiments), very low at 6GeV/c • no thick targets • no backward acceptance (target outside the TPC)

24. HARP (see I.Kato talk) • Inaugurates a new era in Hadron Production for Neutrino Physics: • Based on a design born for Heavy Ions physics studies • Full acceptance with P.Id. • High event rate capability (3KHz on TPC) • Built on purpose • Collaboration includes members of Neutrino Oscillation experiments • And makes measurements on specific targets of existing neutrino beams.

25. HARP physics motivations Input for prediction of neutrino fluxes for the MiniBooNE and K2K experiments Pion/Kaon yield for the design of the proton driver and target system of Neutrino Factories and SPL- based Super-Beams Input for precise calculation of the atmospheric neutrino flux (from yields of secondary p,K) Input for Monte Carlo generators (GEANT4, e.g. for LHC or space applications)

26. HARP’s goals • secondary hadron yields • for different beam momenta • as a function of momentum and angle of daughter particles • for different daughter particles • as close as possible to full acceptance • the aim is to provide measurements with few % overall precision •  efficiencies must be kept under control, down to the level of 1% • primarily trough the use of redundancy from one detector to another • thin, thick and cryogenic targets • T9 secondary beam line on the CERN PS allows a 215 GeV energy range • O(106) events per setting • a setting is defined by a combination of target type and material, beam energy and polarity • Fast readout • aim at ˜103 events/PS spill, one spill=400ms. Event rate ˜ 2.5KHz • corresponds to some 106 events/day •  very demanding (unprecedented!) for the TPC.

27. Data taking summary HARP took data at the CERN PS T9 beamline in 2001-2002 Total: 420 M events, ~300 settings SOLID: n EXP: CRYOGENIC:

28. The Harp detector: Large Acceptance, PID Capabilities , Redundancy Threshold gas Cherenkov: p identification at large Pl TOF: p identification in the low Pl and low Pt region Drift Chambers: Tracking and low Pt spectrometer EM filter (beam muon ID and normalization) Target-Trigger 0.7T solenoidal coil Drift Chambers: Tracking TPC, momentum and PID (dE/dX) at large Pt 1.5 T dipole spectrometer

29. Total Acceptance: 15 GeVp on Be Forward Spectrometer TPC A 4p experiment!!

30. Acceptances & redundancy : an example • Acceptance: PT vs. PL box plot for pions produced in 15 GeV/c interactions of protons on thin Be target • redundancy in overlap regions

31. The Tpc :like a bubble chamber but @3KHz Missing mass distributions  p ->  p p p -> p p Example: Elastic Scattering Target: liquid H2 (cryogenic target) Target length: 18 cm Beam of p and  of 3 GeV/c Red: using dE/dx for PID

32. 2.0 1.5 2.5 0 0.5 1.0 Relevance of HARP for K2K neutrino beam One of the largest K2K systematic errors comes from the uncertainty of the far/near ratio pions producing neutrinos in the oscillation peak To be measured by HARP oscillation peak K2K far/near ratio En(GeV) K2K interest Beam MC confirmed by Pion Monitor Beam MC

33. Preliminary results on K2K target p > 0.2 GeV/c |y | < 50 mrad 25 < |x| < 200 mrad To do: Correction for resolutions Absolute normalisation Empty target subtraction q=0 region, full statistics After efficiency and acceptance correction

34. Y. Fisyak Brookhaven National Laboratory R. Winston EFI, University of Chicago M.Austin,R.J.Peterson University of Colorado, Boulder, E.Swallow Elmhurst College and EFI W.Baker,D.Carey,J.Hylen, C.Johnstone,M.Kostin, H.Meyer, N.Mokhov, A.Para, R.Raja,S. Striganov Fermi National Accelerator Laboratory G. Feldman, A.Lebedev, S.Seun Harvard University P.Hanlet, O.Kamaev,D.Kaplan, H.Rubin,N.Solomey, C.White Illinois Institute of Technology U.Akgun,G.Aydin,F.Duru,Y.Gunyadin,Y.Onel, A.Penzo University of Iowa N.Graf, M. Messier,J.Paley Indiana University P.D.BarnesJr.,E.Hartouni,M.Heffner,D.Lange,R.Soltz, D.Wright Lawrence Livermore Laboratory R.L.Abrams,H.R.Gustafson,M.Longo, H-K.Park, D.Rajaram University of Michigan A.Bujak, L.Gutay,D.E.Miller Purdue University T.Bergfeld,A.Godley,S.R.Mishra,C.Rosenfeld,K.Wu University of South Carolina C.Dukes, H.Lane,L.C.Lu,C.Maternick,K.Nelson,A.Norman University of Virginia ~50 people, 11 graduates students, 11 postdocs.

35. MIPP :Brief Description of Experiment • Approved November 2001 • Techical run 2004 – physics data taking 2005 • Uses 120 GeV Main Injector Primary protons to produce secondary beams of p K  p  from 5 GeV/c to 100 GeV/c to measure particle production cross sections of various nuclei including hydrogen. • Using a TPC can measure momenta of ~all charged particles produced in the interaction and identify the charged particles in the final state using a combination of dE/dx, ToF, differential Cherenkov and RICH technologies. • Open Geometry- Lower systematics. TPC gives high statistics. Existing data poor quality.

36. Particle Physics-To acquire unbiased high statistics data with complete particle id coverage for hadron interactions. Study non-perturbative QCD hadron dynamics, scaling laws of particle production Investigate light meson spectroscopy, pentaquarks, glueballs Nuclear Physics Investigate strangeness production in nuclei- RHIC connection Nuclear scaling Propagation of flavor through nuclei Netrinos related Measurements Atmospheric neutrinos – Cross sections of protons and pions on Nitrogen from 5 GeV- 120 GeV (5,15,25,5070,90) GeV Improve shower models in MARS, Geant4 Make measurements of production of pions for neutrino factory/muon collider targets MINOS target measurements – pion production measurements to control the near/far systematics Complementary with HARP at CERN MIPP :Physics Program

37. MIPP Particle ID capabilities • K/Protonseparation analysis using all systems. • Red = 3s or better. • 3s < Green < 2s • 2s < Blue < 1s • 0s < White < 1 K/π separation p/K separation

38. MIPP Current status Beam Cerenkov Pressure Curve Beam at 45 GeV/c • Commissioning- • Beam tuning going on. • All detectors in readout. Beam chambers fully functional. Drift chambers coming on line. • ToF , Cerenkov in readout • Calorimeters fully operational • TPC in readout. Zero suppression algorithm being worked on. • RICH being refurbished after fire. Should be operational shortly. • Beam Cerenkov pressure curves being taken. • Plans --Continue data taking in 2005. • Tpc electronics upgrading:1KHz TPC installation

39. Future : an Hadron Production for T2K

40. An existing facility :NA49@cern • particle ID in the TPC is augmented by TOFs • leading particles are identified as p or n by a calorimeter in connection with tracking chambers • rate somehow limited (optimized for VERY high multiplicity events). • order 106 event per week is achievable (electronic upgrade needed !) • NA49 is located on the H2 fixed-target station on the CERN SPS. • secondary beams of identified , K, p; 40 to 350 GeV/c momentum • Relevant for atmospheric neutrinos ,NuMI beam & JPARC

41. Or a new experiment ? (Hero)

42. Conclusions • Hadron production for Neutrino Experiments is a well established field since the ’80s • Present trends (Harp & Mipp) • Full-acceptance, low systematic errors • High statistics • Search for smaller and smaller effects characterization of actual neutrino beam targets to reduce MC extrapolation to the minimum • Direct interest of neutrino experiments in hadron production

43. Also in the future the hadron production will be an important ingredient for a successfully neutrino experiment the neutrino beam is part of the experiment, and his knowledge is an unavoidable step