The Other Detectors and Associated R D Jim Brau

The Other Detectors and Associated R&D Jim Brau April 4, 2003 • In addition to the TESLA detector, some other detector configurations have been under study: – JLC Detector – North American SD – North American L (similar to TESLA/JLC) • Different choices have been made, aimed at the same physics Thanks to Y. Fujii, and my NAmer colleagues, for help in preparing this talk Jim Brau, Amsterdam, April 4, 2003 1

2 Comparison of Detector Configurations 144 (Ray Frey) 3 6 o 6 o Jim Brau, Amsterdam, April 4, 2003 2

LC Detector Requirements • Any design must be guided by these goals: – a) Two-jet mass resolution comparable to the natural widths of W and Z for an unambiguous identification of the final states. – b) Excellent flavor-tagging efficiency and purity (for both b- and c-quarks, and hopefully also for s-quarks). – c) Momentum resolution capable of reconstructing the recoilmass to di-muons in Higgs-strahlung with resolution better than beam-energy spread. – d) Hermeticity (both crack-less and coverage to very forward angles) to precisely determine the missing momentum. – e) Timing resolution capable of separating bunch-crossings to suppress overlapping of events. Jim Brau, Amsterdam, April 4, 2003 3

SD (Silicon Detector) • Conceived as a high performance detector for NLC • Reasonably uncompromised performance But • Constrained & Rational cost – parametric cost analysis • Accept the notion that excellent energy flow calorimetry is required, and explore optimization of a Tungsten-Silicon EMCal and the implications for the detector architecture… Recently this configuration has been getting serious attention, as a result of studies being organized by M. Breidenbach Jim Brau, Amsterdam, April 4, 2003 4

Architecture arguments • Silicon is expensive, so limit area by limiting radius • Get back BR 2 by pushing B (~5 T) – This argument may be weak, considering quantitative cost trade-offs. (see plots) • Maintain tracking resolution by using silicon strips • Buy safety margin for VXD with the 5 T B-field. • Keep (? ) track finding by using 5 VXD space points to determine track – tracker measures sagitta. Jim Brau, Amsterdam, April 4, 2003 5

Silicon Tungsten EMCal • Figure of merit something like BR 2/s, – where s = rpixel r. Moliere • Maintain the great Moliere radius of tungsten (9 mm) by minimizing the gaps between ~2. 5 mm tungsten plates. Dilution is (1+Rgap/Rw) – Could a layer of silicon/support/readout etc. fit in a 2. 5 mm gap? (Very Likely) – Even less? ? 1. 5 mm goal? ? (Dubious) • Requires aggressive electronic-mechanical integration! Jim Brau, Amsterdam, April 4, 2003 7

Silicon Tungsten EMCal (cont. ) • Diode pixels ~ 5 mm square on largest hexagon fitting in largest available wafer. – 6” available now – 300 mm when? ? – Consider m tracking as well as E flow in picking pixel dimension. • Develop readout electronics of preamplification through digitization, IO on bump bonded chip. – Upgrade would be full integration of readout on detector wafer. • Optimize shaping time for small diode capacitance. – Probably can do significant bunch localization within train. !!! Jim Brau, Amsterdam, April 4, 2003 8

Structure Pixels on 6” Wafer Jim Brau, Amsterdam, April 4, 2003 9

Thermal Management • Cooling is a fundamental problem: GLAST system is ~2 m. W/channel. Assume 1000 pixels/wafer and power pulsing duty factor for NLC of 10 -3 (10 µsec @120 Hz), for 2 m. W average power. – Preliminary engineering indicates goal of under 100 m. W ok. • Assume fixed temperature heat sink (water cooling) at outer edge of an octant, and conduction through a ~1 mm thick Cu plane sandwiched with the W and G 10: ΔT~140 C. • OK, but need power pulsing!!!. . and maintaining the noise/resolution is a serious engineering challenge. Jim Brau, Amsterdam, April 4, 2003 10

Silicon Tracker • SLC/SLD Prejudice: Silicon is robust against machine mishaps; wires & gas are not. • Mechanical: – Low mass C-Fiber support structure – Chirped Interferometry Geodesy (Oxford System) Atlas has developed a beautiful chirped interferometric alignment system – a full geodetic grid tieing together the elements of their tracker. Can such a system reduce requirements on the space frame precision and stability – reducing its mass and cost? • Silicon Development – Build on GLAST development, • Add double ended bond pads, and • Develop special ladder end detector w/ bump bond array • Reduce mass, complexity at ends • Employ track finding in 5 -layer CCD vertex detector Jim Brau, Amsterdam, April 4, 2003 13

Tracker Electronics • Plan is to string 10 cm square detectors to barrel half lengths and readout from ends. • Design “end” detectors to route strips to rectangular grid for bump bonding to read out chip (ROC). • ROC is ASIC with all preamplification, shaping, discrimination, compression, and transmission functionality. Includes power pulsing. • Hasn’t been done! • Electronics: – Develop RO for half ladder (~1. 5 m) Jim Brau, Amsterdam, April 4, 2003 14

HCal • Hcal assumed to be 4 l thick, with 46 layers 5 cm thick alternating with 1. 5 cm gaps. • Could use “digital” detectors, eg high reliability RPC’s (Have they been invented yet? ? ? ) • Hcal radiator non-magnetic metal – probably copper or stainless – Tungsten much too expensive – Lead possible, but mechanically more painful. • Hcal thickness important cost driver, even though Hcal cost small. – And where is it relative to coil? Jim Brau, Amsterdam, April 4, 2003 15

HCal Location Comparison 80 M$ Scale – Relative to 4 l Inside!! 60 M$ 40 M$ 20 M$ Hcal inside coil 2 l 4 l 2 l 0 M$ 4 l 6 l -10 M$ -20 M$ -30 M$ 6 l HCAL outside coil Coil Jim Brau, Amsterdam, April 4, 2003 16

More Cost trade-offs D $ vs R_Trkr ~1. 7 M$/cm Delta $, Fixed BR 2=5 x 1. 252 Jim Brau, Amsterdam, April 4, 2003 19

Detector R&D in North America • Diversity of R&D projects • Not necessarily aimed at specific detector configurations • Several years of support for simulation is now in transition into invigorated hardware effort – funding for this new era is nearly (but not quite) established Jim Brau, Amsterdam, April 4, 2003 21

A University Program of Accelerator and Detector Research for the Linear Collider http: //www. hep. uiuc. edu/LCRD/html_files/proposal. html In addition focussed R&D effort continues in Canada Jim Brau, Amsterdam, April 4, 2003 22

North American Tracking ALCPG Tracking Working Group: B. Schumm/D. Karlen/K. Riles Jim Brau, Amsterdam, April 4, 2003 23

Gaseous Tracking Jim Brau, Amsterdam, April 4, 2003 24

North American Vertex Detector R&D Oregon/Yale/SLAC Radiation hardness studies removed SLD VXD 3 for analysis Vertex Detector spare ladder studies Developing new CCD detector prototype Studying mechanical issues Design readout for X-Band operation Oklahoma/Boston/Fermilab Development and design of an LC ASIC for CCD readout and data Purdue Study of the Mechanical Behavior of Thin silicon and the Development of hybrid silicon pixels for the LC ALCPG Vertex Detector Working Group: J. Brau, N. Roe Jim Brau, Amsterdam, April 4, 2003 25

ALCPG Calorimeter Working Group: R. Frey/A. Turcot/D. Chakraborty Calorimeter Detector R&D in N. America Jim Brau, Amsterdam, April 4, 2003 26

ALCPG Muon Working Group: G. Fisk Scintillator Based Muon System R&D Jim Brau, Amsterdam, April 4, 2003 29

Beamline Instrumentation • Ongoing R&D Work: – Luminosity • • d. L/d. E analysis (SLAC, Wayne St. ) Beamstrahlung Monitor (Wayne St. ) Pair monitor (Hawaii, in collab. with Tohoku) Forward calorimeter (Iowa St. ) – Energy • WISRD spectrometer (UMass, Oregon) • BPM spectrometer (Notre Dame) – Polarization • x-line simulations (SLAC, Tufts) • Quartz fiber calorimter (Iowa, Tennessee) ® Many important topics uncovered. . . Jim Brau, Amsterdam, April 4, 2003 32

Testbeams • World-wide R&D web page on testbeams: – http: //www-lc. fnal. gov/lc_testbeams/tbpage. html • Assessment underway on testbeam needs and resources Recent study: – Linear Collider Calorimeter Testbeam Study Group Report • S. Magill, J. Repond, A. S. Turcot, J. Yu • http: //www-d 0. fnal. gov/~yu/lc-tb-report. pdf – This report should be broadened to include other subsystems Jim Brau, Amsterdam, April 4, 2003 35

Test Beam Needs (collected by Gene Fisk to date) Jim Brau, Amsterdam, April 4, 2003 36

JLC Design • The JLC strategy for choice of technologies in baseline R&D – 1) No Proof-of-Principle R&D. – 2) Constructible within affordable cost. • JLC official view, as stated in the 'Roadmap Report' (http: //lcdev. kek. jp/RMdraft/ ) – "Extensive R&D studies have been carried out in Asia, Europe, and North America toward the same goal, but with slightly different technology choices in some sub-detectors. International cooperation in common technologies and in crossexamination on different approaches is maintained. Design of the total detector system will be done within a few years by integrating the best technologies achieved. " Jim Brau, Amsterdam, April 4, 2003 37

JLC Detector R&D – 3. 1) Vertex Detector • a) done or finishing soon – excellent spatial resolution (plot) – room-temperature operation (good S/N by Multi-Pinned Phase operation) – radiation hardness measurement : 90 Sr, 252 Cf, electron-beam irradiation=in analysis • b) in progress or to do – CTI improvement : two-phase clocking, thermal charge injection, notch structure (plot) – fast readout : test-board fabrication in progress – thinned CCD (20 micrometer) : flatness, stability, reproducibility – precise estimation of background by a full simulation with detailed beamline components Jim Brau, Amsterdam, April 4, 2003 39

JLC Detector R&D – 3. 2) Intermediate Tracker • in progress or to do – Si-sensor fabrication and test-module construction – Simulation study of VTX-IT-CT combined tracking (plot) – 3. 3) Central Tracker • a) done or finishing soon – – – spatial resolution effect of gas contamination Lorentz angle measurement d. E/dx measurement positive-ion space-charge effect (plot) • b) in progress or to do – Two-track separation performance with a test chamber using parallel laser beam (plot) – Z-measurement with charge-division – Creeping of aluminum wire – Full-simulation study on Pt resolution, bunch-tagging capability, and physics sensitivity Jim Brau, Amsterdam, April 4, 2003 40

JLC Detector R&D – 3. 4) Calorimeter • a) done or finishing soon – hardware compensation, energy response linearity, energy resolution (stochastic term) (plot) – machine-ability of tiny tiles, assemble-ability – performance of WLS-readout SHmax • b) in progress or to do – granularity optimization with a full simulation – photon yield and non-uniformity improvement for Rect. Tile EMcal – performance study of strip-array EMcal : beamtest, simulation, ghostrejection (plot) – direct-APD-readout SHmax – photon detectors (multi-channel HPD/HAPD, EBCCD etc. ) – 3. 5) Muon System • no effort Jim Brau, Amsterdam, April 4, 2003 41

Conclusion There is much to learn from the differing choices of independent groups in the world that are developing full LC detector concepts and studying their advantages and disadvantages. We much do an honest comparison and assessment leading to improved detectors that we will eventually build and use for the LC physics program. Jim Brau, Amsterdam, April 4, 2003 46

Extras Jim Brau, Amsterdam, April 4, 2003 47

EMCal Readout Board Silicon Diode Array Readout Chip Network Interconnect ~1 m Jim Brau, Amsterdam, April 4, 2003 48

Luminosity, Energy, Polarization • Beam Energy DEbeam ~ 200 ppm from 350 - 1000 Te. V Upstream BPM + Downstream WISRD Spect. mmg in forward detector (~200 m. Rad) • Polarization DP/P ~ 0. 25% (Pe- only) DP/P ~ 0. 10% (Pe+ also) Downstream Compton polarimeter t-channel WW scattering Strategy document just completed • Absolute Luminosity DL/L ~ 0. 2% (adequate, not perfect) Forward calorimeter around 50 - 200 m. Rad • Luminosity Spectrum Core width to ~ 0. 1%, tail level to 1% e+e- acolinearity (necessary but not sufficient!) Jim Brau, Amsterdam, April 4, 2003 49

Luminosity Spectrum Acolinearity problems • • • Energy, d. L/d. E both correlated with position along bunch. Measures boost, not s’ Energy imbalance, width imbalance must be input Independent real-time width measurements? 200 u. Rad kicks from disruption alone (larger than target accuraccy) Many other offsets/degrees of freedom which must be input. Putting together complete analysis including ‘realistic’ mis-aligned machine decks from TRC report Jim Brau, Amsterdam, April 4, 2003 50