1 JINR participation in the International Linear Collider Physics and Detector R&D A.Olchevski 99 Session of JINR Scientific Council 19 January 2006 Beam Energy MeasurementBeam Energy Measurement Forward CalorimeterForward Calorimeter Forward TrackingForward Tracking Hadron CalorimeterHadron Calorimeter PhysicsPhysics

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

3 Motivation Development of spectrometer driven by required precision on physics processes to be measured For example, measure top quark to ~ O(100) MeV. Precise knowledge of the beam parameters is needed Continuous monitoring and measurement Important also for other processes ­ Higgsstrahlung, WW production, pair production of exotic particle

4 Responsibility of the Dubna team in the magnetic spectrometer activity Simulation of the magnets Magnetic measurements on the prototype and the design of the instrumentation for it Slow control of spectrometer Alignment and stabilization Application of the synchrotron radiation for the beam energy measurement Production of magnets (in case of acceptance of the project)

5 The efforts of the Dubna team were concentrated on manufacturing of magnetometer instrumentation and generation proposals for solving the problem of 'zero' field measurements. Test bench for the magnetic measurements by the vibrating wire technique (VWT) was designed and manufactured 1 – steel table; 2 – stage with fixed end of wire; 3 – stage with end of wire under tension; 4 – test magnet A first set of experiments on magnetic field measurements were provided and the feasibility of this method was proved

6 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

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

Sampling diamond-tungsten calorimeter Diamond sensors Collaboration High precision design 8 ECFA2005 Electric features: 1.Leakage current. 2.Mip & electric field and dose Some sensors show microcracks (and leakage) The CCDs are between 0 and 150 mm Some are stable under irradiation, other not. Diamond samples (CVD): - Freiburg (FAP) - GPI (Moscow) - Element6 (De Beers)

Particle identification in the BeamCal Motivation The Physics: SUSY particles production  ~ 10 2 fb Signature:  +  - + missing energy The Background: two photons event  ~ 10 6 fb Signature:  +  - + missing energy (if electrons are not tagged) Excellent electron identification is needed down to as small angle as possible 5mm 8mm 10mm E dep vs R

Summary Complete simulation chain for BeamCal exist: – GEANT4 based simulation (A. Elagin) (crossing angle options are available, implemented by V.Drugakov) – eFinder for electron identification (V. Drugakov) 5 mm segmentation is the best for electron identification at small radii 8 mm – is not too bad 10 mm segmentation gives 100% efficiency for R > 55 mm For the control of the systematics the requirements on the control of the LumiCal geometry is almost the same for 2 and 20 mrad, in case the LumiCal is centered around the outgoing beam pipe. (A.Sapronov) LumiCal: BeamCal:

● FCAL Workshop: Workshop on the Simulation of the Very Forward Detectors, Zeuthen, February 2005.Talk was given by A.Elagin (JINR Dubna). ● LCWS05: International Conference on Linear Colliders, Stanford, March 2005.The talk was given by W.Lohmann (DESY Zeuthen) on behalf V.Drugakov (NC HEP Minsk) and A.Elagin (JINR Dubna). ● The results on optimization study were reported at the International Linear Collider Physics and Detector Workshop, Snowmass, August The talk was given by A.Elagin (JINR Dubna). Proceedings will be published by SLAC on the SLAC Electronic Conference Proceedings Archive in December this year. ● The results of LumiCal precision study were reported on the ECFA ILC Workshop, Vienna, November 2005 by A.Sapronov. Results were presented on:

12 FORWARD TRACKING + SIT : (1/p) = 0.5 x GeV -1 SIT: Silicon strips FTD: Silicon disks FTC: Straw tubes, GEMs Design studies in DESY/JINR Taken from W.Lohmann, International School—seminar, Gomel, Belarus, 2005

Design of the package for SI tracker digitization, reconstruction and analysis: - hit map modifiers concept - input, output and temporary hit containers for Si tracker data - access to geometry parameters via run header parameters - global scope geometry object for communication during run-time - universal rules for string keys of run header parameters - optional (parametrical) geometries & technology classification - universal rules for cellID coding for different geometries & technologies - convenient directories/file structure of the package - examples (digitization, reconstruction, analysis) Taken from S.Shulga, III ILC Workshop, Vienna, 2005 LCIO/Marlin based package for Silicon tracker digitization, reconstruction and analysis started in 2005

14 Plans-2006 for Silicon Forward Tracking: - Algorithms and programs for reconstruction of tracks in FTD - Improving the digitization (noises, thresholds, inefficiencies) - Optimization of the performance of the Silicon FTD disks.

15 Presentations (2005): S.Shulga (LPP, JINR), “Silicon Tracker Digitization in MARLIN/DigiSim Framework” ILC Software Mini Workshop, June 27, 2005, DESY, Hamburg S.Shulga (LPP, JINR), ”New Technologies of Programming for HEP on Example of ILC Software”, VIII-th International School-Seminar, August 3, 2005, Gomel, Belarus. S.Shulga (LPP, JINR), “MARLIN processors for Si tracker digitization, reconstruction and analysis”, Seminar of ILC group, November 11, 2005, DESY, Zeuthen. S.Shulga (LPP, JINR), “MARLIN processors for Si tracker digitization, reconstruction and analysis”, III ILC Workshop, November 15, 2005, Vienna, Austria.

16 A Tile-HCAL for the CALICE-LC detector LHE, JINR General requirements –Hermetic –Excellent energy resolution for jets –Excellent angular resolution –Ability to reconstruct non-pointing photons –Good time resolution Biggest issue driving calorimeter design: Jet energy resolution For best jet energy measurements, energy flow algorithms need fine segmentation in the hadron calorimeter. Two options under consideration: Tile-HCAL Digital- HCAL

17 1 m 3 Prototype Beam tests this year!

18 LHE activities Design and construction of a new FEE for the SiPM read-out. Tests of new electronics with the real cassettes. 32 ch FE board 725 Signals from the Tile 725 Results: 32 ch FEE HV adapter VME read-out board VME controller Test of all read-out chain at DESY

19 The group of D.Bardin: Interactive system for automatic complete one-loop calculations of processes

20 Physics

A.N.Skachkova, N.B.Skachkov JINR (Dubna) A.Bartl, W.Majerotto HEPHY (Vienna) HEPHY (Vienna)K.Moenig DESY (Zeuthen) Stop squarks pair production in two-photon collisions at ILC

22 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:

Most important variable is the Invariant mass of Bjet & 2jets W STO P TOP Right edge of M inv ≈ 87,5 GeV M stop – M neutalino = 167 – 80 =87GeV M_inv ( Bjet & 2jets ) = M_top _neutralino M_stop – M_neutralino =√ (P B + Pjet1 W +Pjet2 W ) 2 Reconstruction of Mstop (167 GeV): Reconstruction of Mtop (175 GeV) : Good for Signal / Background separation !

1. The possibility of a good M STOP reconstruction from the right-hand edge point of 3 jets (Bjet + 2jets_ W-decay ) the right-hand edge point of 3 jets (Bjet + 2jets_ W-decay ) invariant mass distribution is demonstrated. invariant mass distribution is demonstrated. 2. It is shown that in a region of small values of stop mass ~ 167 GeV the channel photon-photon → STOP + STOP ~ 167 GeV the channel photon-photon → STOP + STOP is very promissing for STOP squark finding ! is very promissing for STOP squark finding ! 3. STOP MASS (as of the lightest squark) has a very good chance to be determined with a very good chance to be determined with a good precision at ILC in “gamma+gamma” good precision at ILC in “gamma+gamma” collisions. collisions.

25 Conclusion The work at JINR on Physics and Detector for ILC is already going and will be continued in order to provide JINR visible participation in this ambitious project