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The PHENIX Muon Trigger Upgrade. John Lajoie – Iowa State University. Outline: A (Brief) Spin Physics Motivation Antiquark Spin Contribution with W +/- bosons The PHENIX Detector Muon Trigger Upgrade Requirements, implementation and performance.
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The PHENIX Muon Trigger Upgrade John Lajoie – Iowa State University Outline: A (Brief) Spin Physics Motivation Antiquark Spin Contribution with W+/- bosons The PHENIX Detector Muon Trigger Upgrade Requirements, implementation and performance University of Illinois, Abilene Christian, Iowa State University, UC Riverside, University of Colorado, Nevis Laboratory, Riken-BNL Research Center, University of Kyoto, Georgia State University Spin 2006 - J. Lajoie
Flavor separation of the spindependent quark and anti-quark distributions in pp collisions @500GeV For W- interchange u and d. Parity violation of the weak interaction in combination with control over the proton spin orientation gives access to the flavor spin structure in the proton! Experimental Requirements: tracking at high pT good rejection of backgrounds in analysis. event selection for muons difficult due to background muons from hadron decays and beam backgrounds (timing resolution!). W Z Spin 2006 - J. Lajoie
PHENIX Spin Physics Program: ∆g, ∆q/q, ∆q/q, δq • 2 central arms: electrons, photons, hadrons • charmonium J/, ’ -> e+e- • vector mesonr, w, -> e+e- • high pTpo, p+, p- • direct photons • open charm • hadron physics • 2 muon arms: • “onium” J/, ’, -> m+m- • vector meson -> m+m- • open charm Excellent trigger and DAQ capabilities: multiple trigger signature important for spin physics can be taken in parallel with high bandwidth! Spin 2006 - J. Lajoie
Trigger Rate and Rejection REAL DATA Design Luminosity √s = 500 GeV σ=60mb L = 2x1032/cm2/s m momentum dist. At vs=200 GeV PT>10GeV/c HQ signal Total X-sec rate=12MHz PT>20GeV/c W signal DAQ LIMIT =1-2kHz (forμarm) 25 50 Required RF ~ 10,000 Momentum GeV/c Need Momentum Selectivity in the LVL-1 Trigger! Spin 2006 - J. Lajoie
Three dedicated trigger RPC stations (CMS design): • R1(a,b): ~12mm inj, 2 θ pads • R2: ~5.4mm in j , 2 θ pads • R3: ~6.0mm in j, 2 θ pads • (Trigger only – offline segmentation higher) NSF (Funded) • MuTr front end electronics • Upgrade to allow LL1 information JSPS (Funded) PHENIX Muon Trigger Upgrade R2 R3 R1(a+b) r=3.40m r=100-120cm Spin 2006 - J. Lajoie
RPC1(a+b) RPC2 Trigger Algorithm Candidates found by matching RPC1/2 hits within angular range. Momentum cut made by matching hit in MuTr station 2 within three cathode strip2 of RPC projection. Simulations (pythia+PISA): RF= 14,000 @ 500 GeV Spin 2006 - J. Lajoie
~1usec CPA BBCLL1 (3 mV/fC) GL1 MuIDLL1 MuTr FEE Modifications AMU ADC MuTr Cathode DCM 10:90 Split New Board 10mV/fC Pseudo-CFD Hit pattern PA FPGA (MuTrLL1) Discri Spin 2006 - J. Lajoie
Muon Tracker ASD Test Board MuTr Test Bench@ Kyoto Cosmic Ray VDC St#1 built with spare parts at UNM Shipped to Kyoto PCI readout board from Ecole Polytechnique Muon Tracker VDC Spin 2006 - J. Lajoie
Resistive Plate Chambers • good timing performance comparable to that of scintillator (~ 1-2 ns) • space resolution sufficient for muon trigger purpose (~ cm ) • simple design & low cost • arbitrary readout geometry • good rate capability (~several kHz/cm2) • RPC’s have been used in L3, BaBar, Belle experiments. • All 4 LHC experiments will use RPC for muon system. • STAR and PHENIX used MRPC as TOF Spin 2006 - J. Lajoie
DC1/2 RPC Cluster Distributions vs. HV (0.5cm strips) RPC1 8.5kV 8.9kV RPC2 DC3/4 9.3kV 9.5kV RPC Tests (GSU, Colorado, UIUC) Spin 2006 - J. Lajoie
coming from front (in time hits) R1 coming from back (early time hits) R3 R2 Beam-Background Rejection • Severity of beam backgrounds at 500GeV (with high luminosity) is largely unknown. • RPC timing used to eliminate early-time hits. • Trigger rejection largely independent of beam-related backgrounds. Collisions! Beam-Related Background Spin 2006 - J. Lajoie
Physics Timeline see Spin report to DOE http://spin.riken.bnl.gov/rsc/ L= 1x1031cm-2s-1 6x1031cm-2s-1 1.6x1032cm-2s-1 P= 0.5 0.6 0.7 …………………………………… √s= ……………………….. 200 GeV …………………......... 500 GeV| 2005 2006 2007 2008 2009 …. 2012 (RHIC II) 10 pb-1 …………………………………… 275pb-1 …….. 950pb-1 @ 200GeV @ 500GeV Inclusive hadrons + Jets ~ 25% Transverse Physics Charm Physics direct photons bottom physics W-physics ALL(hadrons, Jets) ALL(charm) AL(W) ALL(γ) Spin 2006 - J. Lajoie
Expected Sensitivity with W measurement PHENIX ALW+/-Sensitivity • Machine and detector requirements: • ∫Ldt=800pb-1, P=0.7 at √s=500 GeV • Muon trigger upgrade! 2009 to 2012 running at √s=500 GeV is projected to yield ∫Ldt ~950pb-1 Spin 2006 - J. Lajoie
Summary • The “Spin Crisis” is an opportunity to use spin to probe the structure of the proton! • The polarized proton program at RHIC will address two key pieces of information through W+/- production: • The antiquark spin structure functions • The PHENIX Forward Upgrade will provide the event selection necessary to access this physics: • New RPC-based tracking chambers • New electronics for MuTr LL1 input • New Level-1 Muon Trigger electronics Spin 2006 - J. Lajoie
BACKUP Spin 2006 - J. Lajoie
3 valence quarks + gluons + virtual quark-anti-quark pairs charge momentum mass spin gluon spin ? orbital angular mom. quark spin Includes contributions from the quark sea The Proton as viewed with a high energy (short wavelength) probe as viewed with a low energy (long wavelength) probe 3 valence quarks charge momentum mass spin u ? u d 10-15 m Using spin we can probe the structure of the proton! Spin 2006 - J. Lajoie
OR OR OR OR OR OR MuID LL1 Symset Logic 1A 2A 3A 4A • Either gap 0 or gap 1 • Either gap 3 or gap 4 • Three or more hit gaps • Expected 1D rejection ~500 0B 1B 2B 3B 4B 1C 2C 3C 4C AND S>2 deep Spin 2006 - J. Lajoie
Polarized p-p at RHICA New Experimental Method for the Study of Proton Structure RHIC pC Polarimeters Absolute Polarimeter (H jet) Siberian Snakes BRAHMS & PP2PP PHOBOS Siberian Snakes Spin Flipper PHENIX STAR Spin Rotators Partial Snake Helical Partial Snake Strong Snake Polarized Source Run 05 LINAC AGS BOOSTER 200 MeV Polarimeter <Pb> = 50% Rf Dipole AGS Internal Polarimeter AGS pC Polarimeter Spin 2006 - J. Lajoie
Generic LL1 Board Design (ISU) Fiber Bus Termination 1.8V Regulator Fiber Transceiver/GLINK VME Interface JTAG Connector Xilinx FPGA Logic Spin 2006 - J. Lajoie
Existing MuID LL1 System Another quality product from Iowa State University! accepted event data 16 bits GL1 data blue logic triggers (4 bits per arm shallow/deep) Global Level-1 MuID LL1 backplane backplane GL1-1P GL1-3 GL1-1 GL1-2 GenLL1 GenLL1 20 horizontal fibers 20 vertical fibers 40 Gbit/s per arm! Spin 2006 - J. Lajoie
20 fibers @ 6xBCLK 16-bit backplane bus LL1 Block Diagram (RPC+MuTR) LL1 Block Diagram (RPC) • Key issue is to get the MuID LL1 information into the new LL1’s. New Muon Trigger “LVL1.5” (single board does all) New Muon Trigger “LVL1.5” (each board does two octants) VME crate 40 fibers @ 6xBCLK 56 (48) fibers @ 6xBCLK MuTR 20 Fibers @ 6xBCLK RPC Existing MuID LL1 System Spin 2006 - J. Lajoie
W+ Production in p + p Collisions Weak interaction violates parity – quark/antiquark helicities fixed! (left-handed quarks) (right-handed antiquarks) Spin 2006 - J. Lajoie
Existing MuID Level-1 Trigger Logical tubes formed by OR of physical tubes across panels in each gap. Rejection Factor ~500 @ 200 GeV/c The most probable trajectory for a vertex muon striking a gap-1 logical tube is to continue on a path of equal dx/dz (vertical tubes) or dy/dz (horizontal tubes). Tubes w/ the same dx/dz (or dy/dz) get the same index. Spin 2006 - J. Lajoie