The DØ Calorimeter Upgrade Leslie Groer Columbia University New York September 25, 2000 DØ Offline Calorimeter Workshop Paris, France 1 Leslie Groer Columbia University September 25 -29, 2000 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Outline · Run I D 0 detector u Some measurements · Upgrades to the Tevatron u New beam structure · Upgrades to the D 0 detector u Overview · Upgrades to the Calorimeter Electronics u u u · · 2 Systems Signals Noise Calibration scheme Energy scale optimization Control + Monitoring LAr Monitoring Leslie Groer Columbia University 2 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Tevatron Run I (1992 -96) · Very successful Run I u u p-pbar collisions at √s = 1. 8 Te. V (highest in the world since 1980’s) ò L dt ~ 120 pb-1 delivered to DØ and CDF Peak luminosity ~ 1. 6 x 1031 cm-2 s-1 Many exciting studies, including s Top discovery – Mt = 172. 1 5. 2 (stat. ) 4. 9 (syst. ) Ge. V/c 2 – tt = 5. 9 1. 7 pb (DØ combined) s W mass measurement – MW = 80. 482 ± 0. 091 Ge. V (DØ combined) s s u u 3 Limits on anomolous gauge couplings Limits on SUSY, LQ, compositeness, other exotica Tests of QCD b-quark physics 100+ published papers 60+ Ph. D theses Leslie Groer Columbia University 3 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
DØ Run I Particle Detection Charged Particle Tracks Calorimeter (dense) Absorber Material Interaction Point Tracking Chambers Muon Tracks Energy hadronic EM B electron photon Wire Chambers jet muon neutrino -- or any noninteracting particle missing transverse momentum 4 Leslie Groer Columbia University We know x, y starting momenta is zero, but along the z axis it is not, so many of our measurements are in the xy plane, or transverse 4 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
The Run I DØ Detector • Central tracking (no magnetic field) • U/LAr Calorimeters • Muon Chambers (toroid) (x, y): transverse plane j : azimuthal angle y : polar angle x Pseudorapidity: z 5 Leslie Groer Columbia University 5 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Energy Resolution (e, ) Test Beam e and : 2 Ge. V < Ebeam< 150 Ge. V Fractional resolution: E / E Electrons: E / E = 15% / E + 0. 3% Pions: E / E = 45% / E 6 Leslie Groer Columbia University + 4% 6 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Linearity Use e and beams to find relationship : Charge Voltage (ADC counts) Particle Energy Deviation from linearity Electron : l < 2% above 2 Ge. V Pion : l < 5% above 2 Ge. V E (Ge. V) = a + b EADC 7 Leslie Groer Columbia University 7 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
EM Calorimeter performance · W mass measurement (W e ) Fit m. T m. W = 80. 450 0. 062 Ge. V DØ & CDF combined 8 Leslie Groer Columbia University 8 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Hadronic Calorimeter Performance · · · Examines how well we now the proton structure (PDFs) · Is NLO ( 3) QCD sufficient? · Are quarks composite? Comparison with JETRAD/CTEQ 3 M show no significant deviations from QCD at highest ET Good agreement with theory over 7 orders of magnitude Central Inclusive Jet Cross Section m central S 0. 0 0. 5 JETRAD Uncertainties (%) Jet Energy scale DØ Run 1 B Phys. Rev. Lett. 82, 2451 (1999) Comparison to theory 9 Leslie Groer Columbia University 9 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Fermilab Accelerator Upgrade · Two new machines at FNAL for Run II: u Main Injector s s u 150 Ge. V proton accelerator Supports luminosity upgrade for the collider, future 120 Ge. V fixed-target program, and neutrino production for NUMI Recycler s s 8 Ge. V (monoenergetic) permanent magnet storage ring Permits antiproton recycling from the collider Chicago Booster CDF DØ Tevatron p source 10 Leslie Groer Columbia University Main Injector (new) 10 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Tevatron Status and Schedule · DØ and CDF roll in – January 2001 · Run II start – March 2001 · Center of Mass Energy u 1. 8 Tev 2 Te. V · Goal: u ò L dt = 2 fb-1 by 2003 15 fb-1+ by 2006? · Very first p-pbar collisions seen (August 2000) 11 Leslie Groer Columbia University 11 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Run II Parameters Run II Bunch Spacing % Crossings 40% 12 396 ns 132 ns 30% 20% 10% 0% 0 1 2 3 4 5 6 7 8 9 # of Ints. / Crossing Leslie Groer Columbia University 12 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
The DØ Upgrade · Build on existing strengths (calorimeter and muon detectors) to detect electrons, photons, jets and missing ET · Driven by high-p. T physics program (top, heavy gauge bosons, QCD, new phenomena) but add enhancements for triggering on low p. T · Retain the excellent performance of the Run I detector, especially the calorimetry 13 Leslie Groer Columbia University 13 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
The DØ Upgrade · Add magnetic tracking and b-tagging capabilities u u New solenoid New central tracker and silicon detector · Strengthen the muon system u u u New forward chambers (mini-drift tubes) New shielding around beamline New muon trigger scintillator · Accommodate higher luminosity and shorter bunch spacing u u u New readout electronics; pipelined High rate trigger and DAQ system Radiation hardened elements · Strengthen triggering on low-p. T leptons new muon scintillator for 1. 5 Ge. V dimuon threshold u preshower detectors for low-p. T electron triggers ·. . . and operate at ten times the luminosity of Run I u 14 Leslie Groer Columbia University 14 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
15 Leslie Groer Columbia University The DØ Calorimeter Upgrade Central Scintillator (muon trigger) Forward Scintillator (muon trigger) + New Electronics, Trig, DAQ New Solenoid, Tracking System SMT, Sci. Fi, Preshowers Pseudorapidity = —ln tan ( /2) Shielding Forward Mini-Drift Tubes Run II DØ Upgrade DØ Calibration Workshop Paris, France Sept 2000
Inner Detectors Silicon Microstrip Tracker Fiber Tracker Intercryostat Detector Forward Preshower Solenoid 1. 4 m Central Preshower • • Superconducting solenoid (2 T) 840 k channel silicon vertex detector 77 k channel scintillating fiber tracker Scintillating strip preshower in central and forward regions. (6 k and 16 k channels) • Intercryostat detector (scintillator tiles) 16 Leslie Groer Columbia University 16 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Preshower Detectors · Central mounted on solenoid (| | < 1. 2) · Forward on calorimeter endcaps (1. 4 < | | < 2. 5) · Extruded triangular scintillator strips with embedded WLS fibers and Pb absorber · Trigger on low-p. T EM showers · Reduce overall electron trigger rate by x 3 -5 · VLPC and SVX II readout 17 Leslie Groer Columbia University 17 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Central Preshower · Specifications provide e trig (L 1) & e-ID off-line u 2 X 0 preradiator (solenoid + lead) & triangular strips (axial + 20 o stereo u-v) with VLPC readout u light: 20 p. e. /layer for min. ionizing measured u Central preshower, <1. 3 u reduce e trig by 3 -5 u rad dose: 18 krad - ok 7680 Axial + stereo fibers in extruded triangular strip u 70 cm position resolution (weighted) for mu - (<1. 4 mm for 10 Ge. V e) 18 Leslie Groer Columbia University 18 The DØ Calorimeter Upgrade 7 mm base strips DØ Calibration Workshop Paris, France Sept 2000
Forward Preshower u u u provide e trigger in 1. 4 < | < 2. 5 uses same technology as central preshower (5 mm strip base) 2 x 8 kch, 2 sets of provides 2 -4 rejection in e trig azimuthal u-v scintillator strips with lead in between side view 19 Leslie Groer Columbia University 19 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Intercryostat Detector (ICD) FPS · Objectives u u Maintain ICD performance in presence of a magnetic field and additional material from solenoid Improve coverage for the region 1. 1 < | | < 1. 4 ICD · Design u A scintillator based Intercryostat Detector (ICD) with phototube readout similar to Run I design · Expected Physics output u 20 La. Tech UT, Arlington Provides improvement to jet energies and missing energy in the region between the central and end cryostats Leslie Groer Columbia University 20 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Intercryostat Detector Design · Design u u u u 21 16 supertile modules per cryostat with a total of 384 scintillator tiles WLS fiber readout of scintillator tiles Clear fiber light piping to region of low field. Expect 40 -50% signal loss over 5 -6 m fiber. Re-use existing PMT’s (Hamamatsu R 647). Readout/calibration scheme for electronics same as for L. Ar. Calorimeter but with adapted electronics and pulser shapes LED pulsers used for PMT calibration Relative yields measured > 20 p. e. /m. i. p. Leslie Groer Columbia University 21 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
DØ Calorimeters (1) _ p L. Ar in gap 2. 3 mm p y j x Z Ur absorber 3, 4 or 6 mm · Liquid argon sampling u u Cu pad readout on 4. 6 mm G 10 with resistive coat epoxy Stable, uniform response, rad. hard, fine spatial seg. LAr purity important · Uranium absorber (Cu or Steel for coarse hadronic) u Compensating e/ 1, dense compact · Uniform, hermetic with full coverage u |h| < 4. 2 ( 2 o), l int > 7. 2 (total) · Energy Resolution u u 22 e: E / E = 15% /ÖE + 0. 3% (e. g. 3. 7% @ 20 Ge. V) : E / E = 45% /ÖE + 4% (e. g. 14% @ 20 Ge. V) Leslie Groer Columbia University 22 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
DØ Calorimeters (2) · Arranged in semi-projective towers · Readout cells ganged in layers · Readout segmented into h, for charge detection u u Transverse segmentation Dh x D = 0. 1 x 0. 1 At shower max. (EM 3) Dh x D = 0. 05 x 0. 05 · +2. 5 k. V (E = 11 k. V/cm) gives drift time ~ 450 ns Layer CC EC EM 1, 2, 3, 4 XO : 2, 2, 7, 10 3 mm Ur XO : (0. 3), 3, 8, 9 (1. 4 mm Fe) 4 mm Ur FH 1, 2, 3, (4) O : 1. 3, 1. 0, 0. 9 6 mm Ur O : 1. 3, 1. 2, 1. 2 6 mm Ur O : 3. 0 46. 5 mm Cu O : 3. 0, (3. 0, 3. 0) 46. 5 mm Fe CH 1, (2, 3) Massless Gap (no absorber) Intercryostat Detector (ICD) · Scintillator with photo-tube readout · Improve Ejet and ET measurement / in this region 23 Leslie Groer Columbia University CH OH FH EM MH EM 23 The DØ Calorimeter Upgrade IH DØ Calibration Workshop Paris, France Sept 2000
Timing m. Bunch structure 3. 56 us Run I gap used to form trigger and sample baselines 6 x 6 superbunch gap 4. 36 us 2. 64 us 396 ns Run II 36 x 36 this gap is too small to form trigger and sample baseline · Design all the electronics, triggers and DAQ to handle bunch structure with a minimum of 132 ns between bunches and higher luminosity · Maintain detector performance 24 Leslie Groer Columbia University 24 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Calorimeter Readout Electronics · Objectives u u Accommodate reduced minimum bunch spacing from 3. 5 s to 396 ns or 132 ns and L~ 2 x 1032 cm-2 s-1 Storage of analog signal for 4 s for L 1 trigger formation Generate trigger signals for calorimeter L 1 trigger Maintain present level of noise performance and pile-up performance · Methods LAr det. u u u 25 preamp L 1+L 2 trigger shaper + BLS analog buffer ADC storage Replace preamplifiers, shapers Add analog storage Replace calibration system Replace timing and control system Keep Run I ADCs, crates and most cabling to minimize cost and time Total cost ~ US$4 M Leslie Groer Columbia University 25 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Calorimeter Personnel Physicists, Engineers, Students. . . Calibration BLS, T&C, db Preamps Institution PS, etc. L. Ar Trigger 26 Columbia SUNY, Stony Brook (Rochester) LPNHE, Paris LAL, Orsay Michigan State ISN, Grenoble Mainz, Germany FNAL Leslie Groer Columbia University Name Position Michael Tuts (Project Leader) Leslie Groer Mingcheng Gao Shaohua Fu Al Teho Dean Schamberger Robert Mc. Carthy Mrinmoy Bhattacharjee Moustapha Thioye Vito Manzella Florencia Canelli Ursula Bassler Gregorio Bernardi Frederic Machefert Bob Olivier Herve Lebbolo Alain Vallereau Jean-Francois Huppert Phillipe Bailly Pierre Petroff Melissa Riedel Christophe de la Taille Yves Jacquier Gisele Martin-Chassard Pierre Imbert Patrick Cornebise Reiner Hauser Physicist Student Engineer Physicist Student Engineer Student Physicist Student Engineer Engineer Technician Physicist Gerard Sajot Angste Besson Christian Zeitnitz Karl Jakobson David Huffman Lynn Bagby Patrick Liston Mike Cherry Belinda Jimerson Physicist Student Physicist Engineer Technician Contract Tech. 26 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Calorimeter Electronics Upgrade new calibrated pulse injection SCA analog storage >4 sec, alternate new low noise preamp & driver Trig. sum Bank 0 BLS Card SCA (48 deep) Detc. Filter/ Shaper Preamp/ Driver SCA (48 deep) x 1 x 8 BLS SCA Output Buffer SCA (48 deep) Bank 1 Replace cables for impedence match · · · 27 Shorter shaping ~400 ns Additional buffering for L 2 & L 3 55 K readout channels Replace signal cables from cryostat to preamps (110 30 for impedance match) Replacement of preamps, shapers, baseline subtraction circuitry (BLS) Addition of analog storage (48 -element deep Switched Capacitor Array (SCA)) New Timing and Control New calibration pulser + current cables Leslie Groer Columbia University 27 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Preamplifier similar to Run 1 version except • Dual FET frontend • Compensation for detector capacitance • Faster recovery time New output driver for terminated signal transmission in out preamp driver FET New calorimeter preamp · Hybrid on ceramic · 48 preamps on a motherboard · New low-noise switching power supplies in steel box 2” 28 Leslie Groer Columbia University 28 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Preamp Species Preamp species Avg. Detector cap. (n. F) Layer readou t Feedbac k cap (p. F) RC (ns) Total preamp s A 0. 26 -0. 56 EM 1, 2, HAD 5 0 13376 B 1. 1 -1. 5 HAD 5 26 2240 C 1. 8 -2. 6 HAD 5 53 11008 D 3. 4 -4. 6 HAD 5 109 8912 E 0. 36 -0. 44 CC EM 3 10 0 9920 F 0. 72 -1. 04 EC EM 3, 4 10 14 7712 G 1. 3 -1. 7 CC EM 4, EC EM 3, 4 10 32 3232 Ha-Hg 2 - 4 EC EM 3, 4 10 47 -110 896 · 14+1 (ICD) species of preamp ICD I — 22 0 384 · Feedback provide compensation for RC from detector capacitance and cable impedance 55680 · Readout in towers of up to 12 layers u 0: EM 1, 1: EM 2, 2 -5: EM 3, 6: EM 4, 7 -10: FH, 11: CH · 4 towers per preamp motherboard provides trigger tower (EM+ HAD) of Dh x D = 0. 2 x 0. 2 29 Leslie Groer Columbia University 29 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
BLS Card BLS motherboard v 2. 2 BLS daughterboard L 1 SCAs (2+2) L 2 SCA Array of 48 capacitors to pipeline calorimeter signals ~ 1 inch Output Shapers (12) circuit Trigger pickoff/summers · · · · 30 shaper Use 2 L 1 SCA chips for each x 1/x 8 gain - alternate read/write for each superbunch Readout time ~ 6 s (< length SCA buffer) L 2 SCA buffers readout for transfer to ADC after L 2 trigger decision No dead time for 10 KHz L 1 trigger rate Trigger tower formation (0. 2 x 0. 2) for L 1 Rework existing power supplies New T&C signals to handle SCA requirements and interface to L 1/L 2 trigger system( use FPGAs and FIFOs) Leslie Groer Columbia University 30 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
SCA write address decoder/control reset input. . x 48. . ref cap ref read address decoder/control The DØ Calorimeter Upgrade ed 31 ag Leslie Groer Columbia University 48 deep ck 31 maintain 15 bit dynamic range 12 channels pa · Designed by LBL, FNAL, SUNY Stony Brook (25 k in system) · Not designed for simultaneous read and write operations 1” · two SCA banks alternate reading and writing · 12 bit dynamic range (1/4000) · low and high gain path for each readout channel (X 8/X 1) u out DØ Calibration Workshop Paris, France Sept 2000
Timing and Control System VME backplane (power, ground, communication with BLS and outside world, coordination with other boards) Connectors for communication with ADC (start digitization, BLS sector to digitize) 64 x 36 clocked FPGA FIFO from port A to B FIFO Field Programable Gate Array (FPGA) : 5 v logic, 84 pins 10, 000 gates 32 Leslie Groer Columbia University 32 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Preamp signal shape · Preamp output is integral of detector signal u rise time > 430 ns u recovery time 15 s u To minimize the effects of pileup, only use 2/3 of the charge in the detector · Shaped signal sampled every seven RF buckets (132 ns) Detector signal · BLS-Finite time difference is measured u u Signal from preamp amplitude · peak at about 300 ns u return to zero by about 1. 2 s u Sample at 320 ns u Mostly insensitive to 396 ns or 132 ns running After shaper Uses three samples earlier Pile-up 320 ns 0 35 Leslie Groer Columbia University 35 The DØ Calorimeter Upgrade 400 800 1200 ns DØ Calibration Workshop Paris, France Sept 2000
Noise Contributions · Design for u u u 400 ns shaping lower noise – 2 FET input luminosity of 2 x 1032 cm– 2 s-1 · Re-optimized three contributions u Electronics noise: x 1. 6 s s u Uranium noise: x 2. 3 s u shaping time (2 s 400 ns) (~ t) lower noise preamp (2 FET) (~ 1/ 2) shorter shaping time (~ t) Pile-up noise: x 1. 3 s s luminosity (~ L) shorter shaping times (~ t) ê Comparable noise performance at 1032 with new electronics as with old electronics at 1031 ê Simulations of the W mass “benchmark” confirm that pile-up will not limit our W mass at Run II. 36 Leslie Groer Columbia University 36 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Estimates of Noise Contributions n. F Ge. V Cell Capacitance U noise EM 3 layer per cell Ge. V 3. 5 Me. V Electronic noise 37 Leslie Groer Columbia University Total 37 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Electronics Calibration Goals · Calibrate electronics to better than 1% u u Measure pedestals due to electronics and Ur noise Determine zero suppression limits Determine gains (x 1, x 8) from pulsed channels Study channel-to-channel response; linearity · Commissioning u u Bad channels Trigger verification Check channel mapping Monitoring tool · Oracle Database for storage · Database used to download pedestals and zero-suppression limits to ADC boards 38 Leslie Groer Columbia University 38 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Electronics Calibration System 6 commands (3 x 2) 96 currents PIB Pulser Interface Board: • VME interface • automated calibration procedure switch 2 Fanouts (2 x 3 x 16 switches) Pulser Preamp Box LPNHE-Paris LAL-Orsay Power Supply Trigger Pulser: DC current and command generator: • DC current set by 18 -bit DAC • 96 enable registers • 6 -programmable 8 -bit delays for command signals with 2 ns step size 39 Leslie Groer Columbia University 39 Active Fanout with Switches: pulse shaping and distribution • Open switch when receive command signal The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Calibration Pulser Response · linear response for DAC pulse height (0 -65 k) · Fully saturate ADC (at DAC= 90 k) Single channel (ADC vs. DAC) mean Deviation from linearity · · · better than 0. 2% Linearity of calibration and calorimeter electronics better than 0. 2% (for DAC < 65 k) Cross-talk in neighboring channels < 1. 5% Uniformity of pulser modules better than 1% No significant noise added from the calibration system Correction factors need to be determined 40 Leslie Groer Columbia University 40 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Pulser Signal Shapes Calorimeter Signal at Preamp Input Calorimeter Signal after Preamp and Shaper 400 ns Calibration Signal at Preamp Input Calibration Signal after Preamp and Shaper Signal reflection 400 ns · Response of calorimeter signal w. r. t. calibration signal < 1% at max. signal for variation of different parameters (cable length, Zpreamp, Zcable, …) · No test beam running absolute energy scale will have to be established from the data · Maximum response time for EM and hadronic channels differ due to different preamp types. Use delays and modeling to accommodate these · Correct pulser response for different timings and shape · Use initial “guess” based on Monte-Carlo sampling weights and Spice models of the electronics. 41 Leslie Groer Columbia University 41 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Parts Counts & Status · ~14 systems/cards types; ~170, 000 boards System Part Quant. In hand Preamp Cables 2, 400 Hybrid 60, 000 Motherboard 1, 250 Power supply 24 24 SCA 25, 000 27, 000 Shaper Hybrid 60, 000 Daughtercard 5, 000 550 Trigger sum 10, 000 1* Trig driver 2, 500 1* Backplane 80 80 Motherboard 1, 250 150 Power supply 36 6 Passive fanout 72 72 Plug ins 1150 Cables 144 96 Pulser 13 13 Power supply 15 3 Interface 1 1* 13 2* Shapers (BLS) Calibration Timing & Fanouts *= prototype; red italics indicates critical path Green = production, red = preproduction 42 Leslie Groer Columbia University 42 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Determining EM/Jet Energy Scale · EM Scale Z ee (100 k) sets the absolute EM scale u Check with Z ee u s s u 0 , J/ or (1 S) ee Use W e sample (1. 6 M) to check symmetry in ee J/ ee · Jet Energy Scale u u + jet data possibly also Z + jet, (Z ee/ ) s very low backgrounds and harder Et spectrum but low statistics · We have E/p this time! 43 Leslie Groer Columbia University 43 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
X 0 Effect of added material forward central · New solenoid and preshower detectors increased the radiation length u Degrades both energy response and resolution u Introduces nonuniformity in response 44 Leslie Groer Columbia University 50 Ge. V electron 44 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Optimization of Calorimeter Response E/E · Minimize (Etrue - ai. Ei)2 s ai = layer weighting s Ei = layer Energy · Utilizing these energy correlations improves energy uniformity and resolution by ~10% 50 Ge. V e 45 Leslie Groer Columbia University 45 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Controls and Monitoring · · EPICS** control via python scripts and GUI (Tkinter) Downloads (pedestals, gains etc. ) to crates via VME Controls via VME and MIL-1553 bus and EPICS Front-end VME control boards Power. PC and Motorola 6800 running Vx. Works. Communicate via ethernet and TCP/IP ** Experimental Physics and Industrial Control System – supported by Argonne, Los Alamos, LBL, CEBAF… 46 Leslie Groer Columbia University 46 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Liquid Argon Monitoring · Each cryostat has four cells 241 Am u s s gives about 4 f. C in Lar gap with 500 Hz trigger rate Check LAr response (constant to < 0. 5% in Run I) 106 Ru u s s sources – 5 Me. V , 0. 1 Ci (< 3. 5 Me. V , 1 yr half-life) one stronger source (~10 -10 Ci) should give about 0. 3 Hz triggers (about 2 f. C) Check LAr purity (< 1% in Run I) · Mainz group design (based on ATLAS) u u u 47 Separate HV, preamplifier and trigger system Preamplifier and differential driver give gain of about 50 gives signals of about 0. 1 V Shaping and ADC on receiver boards (FPGA) On board collection and storage of histogram information Extract data over CAN-bus Leslie Groer Columbia University 47 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Conclusions · Dzero is upgrading its detector u L. Argon calorimeter untouched s Harder machine conditions and new environment (solenoid) – New Calorimeter Electronics – Improved ICD – New Central and Forward Preshower Ø Similar performance with 20 x more data · Run II start in 6 months watch this space!!! 48 Leslie Groer Columbia University 48 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Reserve 49 Leslie Groer Columbia University 49 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Physics Goals for Run II * Top quark studies: Measure mtop to ± 3 Ge. V; single top production: width, d. Vtb 0. 1 unique; rare top decays B(t cg)< 2 10 -3 B(t c. Z) < 10 -2 B(t H+b)<15% * W/Z bosons: W mass to < 50 Me. V; WWg, WWZ, ZZg and ZZg couplings at 0. 1 level (large mass scales) ; W and Z forward backward charge asymmetries * Light Higgs: production WH , H bb ( need lum !! ) * New Phenomena: SUSY: mass extended by a factor 1. 5 over Run I, leptoquarks, many topics * B physics: Bs mixing (xs 20); study of heavy b quark mesons (Bc, Bs, Lb), CP violation in Bd J/ Ks; Rare B decays ( Bd mm, Bd Kmm etc) * QCD physics: probe largest Et with jets, production of W/Z, g, b-quarks 51 Leslie Groer Columbia University 51 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Top Mass 52 Leslie Groer Columbia University 52 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Muon System PDTs A- Scint Forward Trigger Scint Shielding Forward Tracker (MDTs) Bottom B/C Scint 53 Leslie Groer Columbia University 53 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Pulser and Fanout Pulser: • DC current set by 18 -bit DAC • 96 enable registers • 6 programmable 8 -bit delays for command signals with 2 ns step size Fan. Out: • switches are opened when receiving a command signal switches generated pulse 54 Leslie Groer Columbia University 54 The DØ Calorimeter Upgrade DØ Calibration Workshop Paris, France Sept 2000
Pulser Uniformity · Cross-talk seen in neighboring channels < 1. 5% · Uniformity of pulser modules better than 1% · In-situ measurements of pulser components (including cables, backplanes) give uniformity better than 1% and linearity better than 0. 5% Fit of slopes vs. DAC setting for all channels Slope/DAC all pulsers Single pulser 1 pulser: used for ICD Dispersion of slopes - below 0. 2% 55 Leslie Groer Columbia University 55 The DØ Calorimeter Upgrade Dispersion of slopes - below 0. 1% DØ Calibration Workshop Paris, France Sept 2000
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