1. 1 JINR participation at Linear Collider Physics and Detector R&D Dubna A.Olchevski 5 th Workshop on the Scientific Cooperation Between German Research Centers and JINR 17-19 January 2005

2. 2 Subjects to cover Beam Energy MeasurementBeam Energy Measurement Forward CalorimeterForward Calorimeter Forward TrackingForward Tracking Hadron CalorimeterHadron Calorimeter PhysicsPhysics

3. 3 The Energy Spectrometer at the ILC DESY – Dubna - TU Berlin Collaboration

4. 4 Physics requirements Mass of top quark: Mass of top quark: (theor. uncertainty ~ 40 MeV) → ΔE b /E b ≈10 -4. (theor. uncertainty ~ 40 MeV) → ΔE b /E b ≈10 -4. Mass of Higgs boson:Mass of Higgs boson: (theor. uncertainty ~ 40 MeV) → ΔE b /E b ≈10 -4 Mass of W-boson:Mass of W-boson: (ΔM W ~ 5 MeV) → ΔE b /E b ≈ 5∙10 -5

5. 5 Main idea of the spectrometer Concept: determination of the bending angle θ of charged particles through a magnet 3 magnets (one analyzing, two ancillary) and a series of BPMs (Beam Position Monitor) Measurements at different nominal LC energies are proposed to be performed at constant θ by adjusting the current to the magnets. Θ = bending angle → B= magnetic field

6. 6 Responsibility of Dubna team Simulation of the magnetsSimulation of the magnets Magnetic measurements on the prototype and the design of the instrumentation for itMagnetic measurements on the prototype and the design of the instrumentation for it Slow control of spectrometerSlow control of spectrometer Alignment and stabilizationAlignment and stabilization Production of magnets (in case of acceptance of the project)Production of magnets (in case of acceptance of the project)

7. 7 Simulation of the magnets was performed

8. 8 Main parts of magnetometers are designed

9. 9 Dubna magnetometers S.Ivashkevitch

10. 10 Analysis of stability and alignment is in progress Solutions and proposals construct the spectrometer on a single girder (grounded to the floor, ~25 m long, control its stability )construct the spectrometer on a single girder (grounded to the floor, ~25 m long, control its stability ) BPM-positioning needed ~ 10 µm (laser interferometer resp. piezoelectrical devices or flexible bearings)BPM-positioning needed ~ 10 µm (laser interferometer resp. piezoelectrical devices or flexible bearings) B-field stability and controlB-field stability and control → power and temperature control → power and temperature control → permanent field measurements with two. complementary methods → permanent field measurements with two. complementary methods Stability will be a key issue

11. 11 Cost estimate was performed

12. 12 Complementary methods for beam energy determination Complementary methods for beam energy determination SR produced in magnets of the spectrometer (Dubna- Lomonosov MSU) – simulation, technical evaluationSR produced in magnets of the spectrometer (Dubna- Lomonosov MSU) – simulation, technical evaluation resonance absorption of laser light (YerPhI, Armenia - Dubna ) – theoretical estimation, simulationresonance absorption of laser light (YerPhI, Armenia - Dubna ) – theoretical estimation, simulation radiative return using e.g. e + e - -> µ + µ - (Dubna) – theoretical estimations radiative return using e.g. e + e - -> µ + µ - (Dubna) – theoretical estimations polarization rotation measurementspolarization rotation measurements Moller scatteringMoller scattering CROSS-CHECKS needed Details are available on the Workshops Home Page http://www-zeuthen.desy.de/main/html/aktuelles/workshops.html

13. 13 Forward Calorimetry activities 1. CVD Diamond sensors. GPI-JINR-DESY 2. Simulation. JINR-DESY 3. Physics. JINR-DESY

14. 14 The complete system combines the microwave plasma reactor, vacuum and gas distribution system and instrumentation rack. The system is computer controlled.  Microwave power source - 6 kW at 2.45 GHz, variable output  Reaction gases: CH 4, H 2 (O 2, Ar or CO 2 optional)  Gas is distributed with four mass flow controllers  Gas process pressure: 20-120 Torr  Substrate diameter: 76 mm (thick films), up to 100 mm (thin films)  Substrate temperature control with a pyrometer  Growth rate: 0.8 – 2.5 microns/hour (optical quality material)  Diagnostic ports: 4 quartz windows  Chamber: stainless steel, water cooled

15. 15 Fig. 1. Responsivity (a.u.) vs photon energy for a diamond film of 0.28 thickness measured on the growth side (red squares) and nucleation side (blue circles) of the sample. Bias voltage is 50 V. Open circles – the response on growth side at 10 V bias voltage. 25 microns were polished away from the nucleation side to remove the most defective material.

16. 16 Fig.2. Alpha spectrum ( 241 Am) for CVD-det. #5 at bias +500 V on rear contact. Test pulse is 14.4 fC (86400 e), 1ch. ADC=40 e.

17. 17 Shower from 50 GeV electron Energy deposition in diamond Simulation program

18. 18 Non radiative Bhabha (only e + or e - in the final state) All events with e + and e - in the final state Total Bhabha cross section Cross section vs energy cut Events per bunch vs energy cut Bhabha scattering simulation (in BeamCal angle range)

19. 19 BHLUMI TEEGG electron angular distribution for completely coincident events we have: Xsec_teegg = 31.655 ± 0.483 nb Xsec_bhlumi = 30.426 ± 0.321 nb TEEGG after cut for minimum scattered angle (0.5 mrad)

20. 20 F ORWARD CH AMBERS OF THE LC DETECTOR  General layout of one quarter of the central tracking

21. 21 TRACK PERFORMANCE IN THE FCH (soft selection rules 2/2/2)  Soft selection rules (2/2/2 from 12) have been applied for further studies of the FCH performance: minimum 2 hits are required for each of 3 projections of a track  In ideal case: no dead zones and wire noise, wire efficiency = 100%  tracking efficiency  87% for tracks originating from the e + e - - interaction point  82% for all tracks  Mean efficiency, ghost & clone rates vrs drift-tube space resolution: Wire efficiency = 100% Wire-noise probability = 0% -- only for tracks originating from the e + e - - interaction point -- for all tracks Small dependence on the drift-tube space resolution

22. 22 TRACK PERFORMANCE IN THE FCH (soft selection rules 2/2/2)  Mean efficiency, ghost & clone rates for various wire efficiencies and wire noise level ( for all tracks in the FCH)  Mean efficiency, ghost & clone rates for various wire efficiencies and wire noise level ( for tracks originating from the e + e - - interaction point) Drift-tube space resolution = 50 µm

23. 23 The First tests of pilot fast digitization unit for the Tile HCAL

24. 24 -E 10 kOhm 470 Ohm SiPM 50v 100 Ohm 12 kOhm 22 n

25. 25

26. 26

27. 27 5:12

28. 28 Results for pilot TileCal electronics: 1.The 32ch unit was designed, built and successfully tested 2.Single photoelectron peaks can be measured 3.The possibility of calibration in the self-trigger mode is shown 4.Dynamic range is estimated to be not less than 50 MIPs 5.Time resolution at least 2 ns is obtained 6.Cross-talk between neighbour channels is measured at the level of about 0,25% 7.More studies are needed (RC, stability, time resolution) 8.Many solutions for the DAQ system is reserved in the design of the module and should be discussed

29. 29 Physics

30. 30

31. 31

32. 32 SUSY study at ILC: Main task: STOP- squarks pair production in polarized PHOTON-PHOTON collisions Authors/Participants: Authors/Participants: A.Skachkova, N.Skachkov ( Dubna ) A.Skachkova, N.Skachkov ( Dubna ) K.Moenig ( DESY, Zeuthen ) K.Moenig ( DESY, Zeuthen ) A.Bartl, ( University, Wien ) A.Bartl, ( University, Wien ) W.Majerotto ( HEPHY, Wien ) W.Majerotto ( HEPHY, Wien ) April 2004-  April 2004-  talk given at LCWS2004, Paris talk given at LCWS2004, Paris (to appear in Proccedings of (to appear in Proccedings of this Conference) this Conference) In STANDARD MODEL: TOP-quark is the heaviest one In SUSY: STOP-squark  the lightest one i.e. STOPs have better chances to be discovered ! Studied process (at Etot = 1GeV ) : gamma-gamma   STOP + antiSTOP

33. 33 MSSM model was used with: M_gluino = M_squark = 370 GeV, it corresponds to M_stop1 = 167 GeV. Main background: Final states were defined by 2 decay channels: SIGNAL: BACKGROUND:

34. 34 STOP/Top production processes have the same observable particles in final states! (differ only by neutralino pair presence in STOP case) The authors find out a set of physical observables which distibutions look very different for signal and background. For example: For example: 1. Total energy, deposited in Calorimeter (fig.1,1. Total energy, deposited in Calorimeter (fig.1, red is STOP, green is top): red is STOP, green is top): E_cal_tot. E_cal_tot. 2. Invariant mass of two b_jets (fig.2): M_Bjet_Bbarjet2. Invariant mass of two b_jets (fig.2): M_Bjet_Bbarjet

35. 35 Analogous effect was shown for two other invariant masses. Important: All figures 1-4 look much more better than in LHC case, i.e. LC may be better suited for stop pair study than gluon-gluon channel at LHC 3. Distributions for invariant mass of b-jet and of two quark jets from W decay in STOP/top cases (fig.3, red is STOP, green is top): M_Bjet1_Jet2. M_Bjet1_Jet2. 4. Invariant mass of two b-jets + two jets from one W decay and of muon from another W decay (fig.4): M_4jet_mu.

36. 36 Conclusion the work on Instrumentation, Software, Simulation and Physics should be continued