U N C L A S S I F I E D Precision Tracking for the PHENIX Muon Arms Gerd J. Kunde ASI Prague 2005 U N C L A S S I F I E D 78 cm 66 cm 45 cm 3 The Central Region U N C L A S S I F I E D Overview of Heavy Ion Goals A new state of matter, the quark-gluon plasma QGP, is being probed in collisions of heavy ions at RHIC Heavy quarks (charm and beauty) are the cleanest probes of QGP. Next frontier of heavy ion physics We will construct a forward silicon vertex tracker for the PHENIX muon arms unique heavy quark experimental capability new asynchronous readout technology U N C L A S S I F I E D Why Heavy Quarks in Heavy Ion Collisions ? Heavy quarks (charm and beauty) produced early in the collision. Live long enough to sample the plasma Intrinsic large mass scale (heavy quarks) allows for precise calculations Determination of QGP properties viscosity and conductivity energy density and temperature Distinguish between energy loss models Heavy quarks provide the best quantitative determination of the properties of the plasma U N C L A S S I F I E D Photon detection at forward /backward rapidity Measurement of gluon structure in nuclei, contrast with heavy quark data. Detection of C states via C J/ + . Large acceptance since nosecone calorimeter covers muon arm rapidity range. (Acceptance for photon in central arms is very low.) C is a QGP diagnostic plus a contributor to J/ yield. Can use q + g + jet for very clean gluon measurement. Should have better x resolution than inclusive channels. Large acceptance for (0.9 < | | with Endcap VTX Decay Distance (cm) 1mm vertex cut eliminates >99.95% of prompt J/ B decays Prompt J/ 1mm cut Ratio of B decay to prompt J/ ~ 1% =133 RHIC 10*L 0 ~400 B-> J/ per day p+p S=200 GeV L=10 36 Events U N C L A S S I F I E D Recreating the Early Universe Heavy ion accelerators recreate the same conditions Relativistic Heavy Ion Collider at Brookhaven Natl Lab U N C L A S S I F I E D Hottest and Densest Plasma Ever U N C L A S S I F I E D Au+Au d+Au Energetic quarks experience large energy loss in the QGP Au Au R AA Strong suppression of pions in Au+Au compared to control: p+p and d+Au collisions Evidence for Strongly Interacting Opaque Plasma Data - PHENIX Predictions Ivan Vitev Absence of QGP would yield U N C L A S S I F I E D Muon Arm Au The PHENIX detector Muon trackers designed and built by LANL Very successful program for J/psi physics U N C L A S S I F I E D Open Charm Forward Rapidity Si Endcaps Inclusive D=> +X dominated by , K decays Cut: muon from within 1cm of collision removes most muons from , K decay high-statistics, robust charm same y, pt range as J/ => critical for normalization U N C L A S S I F I E D Example, B J/ pz (GeV/c) x1 B => J/ utilizing large acceptance muon arms z vertex (cm) direct J/ J/ from B -> Phenix high rate e.g. with z vertex > 0.1cm p+p: J/ ~20K/year Au+Au: J/ ~7K/year 0.8% U N C L A S S I F I E D Improved Endcap Mass Resolution U N C L A S S I F I E D D,B Detection of decay vertex will allow for clean identifications of charm and bottom decays m c GeV m D D B B Direct Observation of Open Charm and Beauty Au e, Au D X J/ B K Need secondary vertex resolution < 50 m (barrel) < 150 m (endcap) e, U N C L A S S I F I E D Silicon Vertex Tracker Upgrade for Charm and Beauty Pinpoints decay vertex Tracker detects heavy quarks by displaced vertex of muons: D + X B + X B J/ + X + - Silicon planes with radial mini strips Asynchronous readout electronics U N C L A S S I F I E D Silicon Tracker Details Four umbrella stations on each side Mini-strips of 50 micron * mm Readout via new PHX chip from Fermi Natl Lab Zero suppressed, 3bit ADC, asynchronous Data push via 2.5 gigabit optical links (OASE) Total channel count: ~1.7 million channels Total chip count: ~ 3500 chips Total silicon area: ~ 6500 cm 2 U N C L A S S I F I E D Precision Silicon Tracker for the Muon-Arms Adding displaced track and displaced vertex capability to muon tracker Asynchronous readout technology being developed with FNAL U N C L A S S I F I E D Endcap Acceptance Colored Area: 3 or more silicon hits Yellow line in left figure No perfect match with Ncc or Muons because of HBD constrains Will there ever be a run with both FVTX and HBD - in place ???? U N C L A S S I F I E D 78 cm 66 cm 45 cm 3 The Acceptance . U N C L A S S I F I E D Endcap Technical Overview 50 micron radial pitch (z reconstruction) 4608 (4096) mini-strips 3.5 cm < r < 18 (14) cm < 1 % occupancy 48 double towers in phi mini-strips from 13.0 mm to 2.2 mm readout via one PHX chip row r = 3.5 cm r = 18.0 cm 1 r = 14.0 cm Derived from FNAL chips U N C L A S S I F I E D Only 2 Silicon Detector types Inside Detector (I) Outside Detector (II) Outside Detector (III) 5 chips= 2560 strips 6 chips= 3072 strips 3 chips= 1536 strips 50 micron strips (collaboration with Prague groups ?) U N C L A S S I F I E D Wedge Assembly 3 mm carbon wedge for assembly and cooling 2 silicons in front 2 silicons in back Reason: Eliminate dead silicon areas by overlapping 1 mm along edges . U N C L A S S I F I E D From Wedges to Umbrellas X 24 U N C L A S S I F I E D Endcap with Readout Board(green) and fiber optic connector(orange) 12 fibers per connector 30 U N C L A S S I F I E D PHX Chip Layout: 2 columns 256 channels/column 3.8 mm x 13 mm = 49.4 mm 2 Bump bonds on 200 um pitch 50 m dia bumps 512 bumps plus inter-chip bumps FPIX2 Layout for comparison: Chip area = 91 mm 2 Bump bonds on 50 m pitch 12 m dia bumps 2816 bumps signals & power FNAL Collaboration BNL money ? U N C L A S S I F I E D PHX: Tower Section Carbon Fiber Support and Cooling U N C L A S S I F I E D Endcap Readout: Front End 6 x 512 channels 5 x 512 channels Fiber 2.5 Gbit/s Slow Control ~100 Hz RISC onboard OASE chip LVDS 6 x 160 MBit PHX/FPIX2 is zerosupressed !!! Hit: 9 bit address,3 bit adc, 4 bit chip-id, tag 8bit, i.e.24 bits 1 % Occupancy translates into: 60 x 24-bits in J/ Open Charm Measurement D=> +X, D D=> +e+X, D D=> + + - +X cc (displaced)X B J/ X bb e/ +displaced cc (displaced)X B J/ Xg GS95 bb e/ +displaced p-p p-A A-A /100 U N C L A S S I F I E D Summary Next Step in Heavy Ion Physics with Endcap FVTX Charm and Beauty Precision Tracking before NCC and Muon Arms Heavy-Ion Physics with together with NCC will be Gamma Tags and Xc Preparation for DOE proposal in progress DIRECTED RESEARCH proposal to LANL (made 1 st cut) R&D Contract with FNAL (future will be PHX support through BNL) Collaboration with Prague groups on silicon detector ! With the Endcap FVTX, Nosecone Calorimeter NCC and Muon Trigger Upgrades Finally exploit the full rare probe capabilities of PHENIX. Push deep into the shadowing / CGC region. Directly measure heavy quarks Measure hadrons and photons at forward/backward rapidities Gamma tagged Jets Detect W decays C !!!!!