Detector description for fast simulation

1. Detector description for fast simulation as used by theVienna Fast Simulation Tool for Charged Tracks(“LiC Detector Toy”)

2. Why fast simulation? • Achieve quick response to local detector modifications, but not intended to replace full simulation • Doesn’t make sense to try detector modifications using the full simulation and reconstruction chain MOKKA/MARLIN (distributed among different institutes, would take months) • Use full simulation to make an ‘ultimate check’ on a promising detector modification • Simple to use, even by non experts • Doesn’t demand much preparation time • Quick results, can be installed on a laptop • Effect of various detector modifications can quickly be resolved • Human readable, simplified detector description should be standardized to make results comparable

3. The Vienna Fast Simulation Tool • Simple, but flexible and powerful tool, written in MatLab • Detector design studies • Geometry: cylinders (barrel) or planes (forward/rear) • Material budget, resolutions, inefficiencies • Simulation • Solenoid magnetic field, helix track model • Multiple scattering, measurement errors and inefficiencies • No further corruption, therefore no pattern recognition • Strips and pads, uniform and gaussian errors (in TPC with diffusion corr.) • Reconstruction • Kalman filter • Optimal linear estimator according to Gauss-Markov (no corruption) • Fitted parameters and corresponding covariances at the beamtube • Output • Resolution of the reconstructed track parameters inside the beam tube • Impact parameters (projected and in space) • Test quantities (pulls, χ2, etc.)

4. Subsequent Vertex Fit • Fitted tracks as input to the VERTIGO/RAVE toolkit; • Interface is the Harvester‘s standard CSV format; • Successfully tested with 10- and 1000-prong events. Tracks from barrel region Tracks from forward region

5. Basic detector description(VTX) [1]: Detector Outline Document (DOD) for the LDC, Aug. 2006 [2]: M. Vos: Pixel R&D at IFIC Valencia, SiLC Meeting, Torino, Dec. 2007

6. Basic detector description(SIT, SET) [3]: V. Saveliev, A. Savoy-Navarro, M. Vos: Silicon Tracking, ILD Meeting, Zeuthen, Jan. 2008 [4]: M. Vos: The silicon tracker elements, SiLC phone conference, 06.02.2008

7. Basic detector description(TPC) [5]: R. Settles: E-mail communication, 25.01.2008 [6]: V. Lepeltier: Private communication, 2006 [7]: MOKKA Database, http://www-flc.desy.de/ldcoptimization/tools/mokkamodels.php

8. Basic detector description (forward/rear)

9. Basic detector description (forward/rear)

10. Display of basic detector description

11. Display of basic detector description

12. Barrel input sheet 04 Vertex Detector (VTX) 05 06 Number of layers : 6 07 Description (optional) : |-Beamt.-|----------Vertex detector------------| 08 Names of the layers (opt.) : XBT, VTX1, VTX2, VTX3, VTX4, VTX5 09 Radii [mm] : 14, 16, 26, 37, 48, 60, 10 Upper limit in z [mm] : 3000, 50, 120, 120, 120, 120 11 Lower limit in z [mm] : -3000, -50, -120, -120, -120, -120 12 Efficiency RPhi : 0, 0.95, 0.95, 0.95, 0.95, 0.95 13 Efficiency 2nd coord. (eg. z): -1 14 Stereo angle alpha [Rad] : pi/2 15 Thickness [rad. lengths] : 0.0025, 0.0014, 0.0014, 0.0014, 0.0014, 0.0014 16 error distribution : 1 17 0 normal-sigma(RPhi) [1e-6m] : 18 sigma(z) [1e-6m] : 19 1 uniform-d(RPhi) [1e-6m] : 24 20 d(z) [1e-6m] : 24 21 22 Silicon Inner Tracker (SIT) 23 24 Number of layers : 3 25 Description (optional) : |--Inner tracker--|TPC inner wall| 26 Names of the layers (opt.) : SIT1, SIT2, XTPCW 27 Radii [mm] : 160, 270, 300 28 Upper limit in z [mm] : 380, 660, 2160 29 Lower limit in z [mm] : -380, -660, -2160 30 Efficiency RPhi : 0.95, 0.95, 0 31 Efficiency 2nd coord. (eg. z): 0.95, 0.95, -1 32 Stereo angle alpha [Rad] : pi/2 33 Thickness [rad. lengths] : 0.005, 0.005, 0.0116 34 error distribution : 1 35 0 normal-sigma(RPhi) [1e-6m] : 36 sigma(z) [1e-6m] : 37 1 uniform-d(RPhi) [1e-6m] : 35 38 d(z) [1e-6m] : 35 39

13. Barrel input sheet 40 Time Projection Chamber (TPC) 41 sigma^2=sigma0^2+sigma1^2*sin(beta)^2+Cdiff^2*6mm/h*sin(theta)*Ldrift[m] 42 Number of layers : 196 43 Radii [mm] : 300,1580 44 Upper limit in z [mm] : 2160 45 Lower limit in z [mm] : -2160 46 Efficiency RPhi : 0.999 47 Efficiency z : 0.999 48 Thickness [rad. lengths] : 0.0000125 49 sigma0(RPhi) [1e-6m] : 50 50 sigma1(RPhi) [1e-6m] : 900 51 Cdiff(RPhi) [1e-6m/sqrt(m)] : 53 52 sigma0(z) [1e-6m] : 15 53 sigma1(z) [1e-6m] : 0 54 Cdiff(z) [1e-6m/sqrt(m)] : 580 55 56 Silicon External Tracker (SET) 57 58 Number of layers : 3 59 Description (optional) : |TPC outer wall|-External Tracker-| 60 Names of the layers (opt.) : XTPCW2, SET1, SET2 61 Radii [mm] : 1580, 1600, 1610 62 Upper limit in z [mm] : 2160, 2500, 2500 63 Lower limit in z [mm] : -2160, -2500, -2500 64 Efficiency RPhi : 0, 0.95, 0.95 65 Efficiency 2nd coord. (eg. z): -1, 0.95, 0.95 66 Stereo angle alpha [Rad] : pi/2 67 Thickness [rad. lengths] : 0.0151 0.0065, 0.0065 68 error distribution : 1 69 0 normal-sigma(RPhi) [1e-6m] : 70 sigma(z) [1e-6m] : 71 1 uniform-d(RPhi) [1e-6m] : 50 72 d(z) [1e-6m] : 50 73 74 Magnetic field and beam spot 75 76 Solenoid magnetic field [T] : 4 77 Range in x [mm] : -0.0021 0.0021 78 Range in y [mm] : -1e-05 1e-05 79 Range in z [mm] : -1.04 1.04

14. Barrel input sheet 04 Forward module 1 05 06 Number of layers : 3 07 Description (optional) : 08 Names of the layers (opt.): FTD1, FTD2, FTD3 09 z positions [mm] : 220, 350, 500 10 Inner radius [mm] : 29, 32, 35 11 Outer radius [mm] : 140, 140, 210 12 Efficiency u : 0.95 13 Efficiency v : -1 14 Angle 1st coord. (u) [Rad]: 0 15 Angle 2nd coord. (v) [Rad]: pi/2 16 Thickness [rad. lengths] : 0.003 17 error distribution : 1 18 0 normal-sigma(u) [1e-6m] : 19 sigma(v) [1e-6m] : 20 1 uniform-d(u) [1e-6m] : 35 21 d(v) [1e-6m] : 35 22 23 Forward module 2 24 25 Number of layers : 4 26 Description (optional) : 27 Names of the layers (opt.): FTD4, FTD5, FTD6, FTD7, XTPCEC 28 z positions [mm] : 850, 1200, 1550, 1900, 2160 29 Inner radius [mm] : 51, 72, 93, 113, 300 30 Outer radius [mm] : 270, 290, 290, 290, 1580 31 Efficiency u : 0.95, 0.95, 0.95, 0.95, 0 32 Efficiency v : 0.95, 0.95, 0.95, 0.95, -1 33 Angle 1st coord. (u) [Rad]: 0*pi/180 34 Angle 2nd coord. (v) [Rad]: 90*pi/180 35 Thickness [rad. lengths] : 0.003,0.003, 0.003, 0.003, 0.15 36 error distribution : 1 37 0 normal-sigma(u) [1e-6m] : 38 sigma(v) [1e-6m] : 39 1 uniform-d(u) [1e-6m] : 35 40 d(v) [1e-6m] : 35 41 42 Rear module 1 43 44 Number of layers : -1 45 Description (optional) : 46 Names of the layers (opt.): 47 z positions [mm] : 48 Inner radius [mm] : 49 Outer radius [mm] : 50 Efficiency u : 51 Efficiency v : 52 Angle 1st coord. (u) [Rad]: 53 Angle 2nd coord. (v) [Rad]: 54 Thickness [rad. lengths] : 55 error distribution : 56 0 normal-sigma(u) [1e-6m] : 57 sigma(v) [1e-6m] : 58 1 uniform-d(u) [1e-6m] : 59 d(v) [1e-6m] : 60 61 Rear module 2 62 63 Number of layers : -1 64 Description (optional) : 65 Names of the layers (opt.): 66 z positions [mm] : 67 Inner radius [mm] : 68 Outer radius [mm] : 69 Efficiency u : 70 Efficiency v : 71 Angle 1st coord. (u) [Rad]: 72 Angle 2nd coord. (v) [Rad]: 73 Thickness [rad. lengths] : 74 error distribution : 75 0 normal-sigma(u) [1e-6m] : 76 sigma(v) [1e-6m] : 77 1 uniform-d(u) [1e-6m] : 78 d(v) [1e-6m] :

15. DETECTOR DESCRIPTION FOR FAST SIMULATION • BASIC IDEA: • Parallel to full detector description, define a basic detector description, limited to cylinders in the barrel and planes in the forward region. • It should serve as a starting point for local detector studies of the trackers. • Without agreement on a common starting version results of different detector optimization studies will never be comparable (neither with fast simulation, nor with MOKKA/MARLIN). • Increases flexibility and speed, and yields useful and comparable results, which may be validated by full simulation once in a while.

16. The Vienna Fast Simulation Tool for charged tracks (LDT). Info on the web: http://stop.itp.tuwien.ac.at/websvn/ ==> lictoy Acknowledgements The software was designed and developed by the Vienna ILC Project Group in response to encouragement from the SiLC R&D Project. Efficient helix tracking was actively supported by W. Mitaroff. Special thanks are due to R. Frühwirth for the Kalman filter algorithms used in the program.