C. Schwarz Physics with Antiprotons - Detector - Detector requirements Overview of the detector concept Detector components Trigger Costs

C. Schwarz Detector requirements (simulations) Energy release of charmed hadrons high → large p trans → large angles High cm-velocity (fixed target) → high energies → small angles Formation of Ψ’ and decay in muons Ψ’→μ + μ - Ψ’→J/Ψ + X ↓ μ + μ - electrons similar → calorimeter for large angles.

C. Schwarz Detector requirements (PID) Forward angles need π/K separation up to 3 GeV/c: Cherenkov n=1.02 Backward: higher value of n. p+p → ΦΦ→ 4K s ½ =3.6 GeV

C. Schwarz Overview of detector concept internal target forward spectrometertarget spectrometer Heavy charmed mesons decay in light products with large p t. Solenoid is important. top view

C. Schwarz Overview of detector concept side view

C. Schwarz

Central tracking: Microvertex Detector 7.2 mio. barrel pixels 50 x 300 μm 2 mio. forward pixels 100 x 150 μm beam pipe pellet pipe Space resol.: σ z =80μm, σ r-φ =15μm Track resol. : σ L = μm σ T =12μm Readout: ASICs (ATLAS/CMS) 0.37% X 0 or pixel one side – readout other side (TESLA)

C. Schwarz Central tracking: Straw tubes 15 skewed double layers to remove left-right ambiguity Ø 4-8 mm skew angle: 5-15 o p+p → φ φ → K + K - K + K -

C. Schwarz Mini Drift Chambers 6 layers of sense wires in 3 double layers (y,u,v) not stretched radially (mass) realized at HADES expected counting rates position resolution 70μm

C. Schwarz Particle identification PID from 0 0 <Θ<5 0 hadronic calorimeter 5 0 <Θ<22 0 Aerogel Cherenkov Counters 22 0 <Θ<140 0 DIRC DIRC thickness: 0.19 X 0

C. Schwarz Cherenkov opening angle: Internal reflection → different vel. thresholds p + p → 8.5AGeV/c ε=80% PID: DIRC

C. Schwarz Calorimeter PbWO 4 Length = 17 X 0 APD readout (in field) σ(E) = 1.54% / E ½ + 0.3% pp  J/Ψ + η γγ 140 o 5o5o 22 o

C. Schwarz e ± /π ± sep. electron/pion separation  p (GeV/c) 0 E dep (GeV/c) e +/- π+π+ 2468p (GeV/c) π + probability

C. Schwarz Trigger Front end and DAQ structure pipelining 3-level trigger Ex.: HADES/LHCb LVL-1: <10 6 events/s J/ψ large p T (e, μ) neutral K, hyperons: multiplicity jump in MVD D-meson: vertex LVL-2: <10 4 events/s Pattern recognition EMC: em. shower photon reconstruction M inv from EMC or muons LVL-3: <10 3 event/s global kin. conditions

C. Schwarz Pellet target Frozen hydrogen pellets 20-40μm Δx=±1 mm (±0.04 o ) 60 m/s pellets/sec atoms/cm 2 (avg.) 1 mm

C. Schwarz Costs Solenoid 2.5 M€ Calorimeter (target spectrometer) 12.5 M€ Tracking ( pixel detector, straw tubes) 3.0 M€ Cherenkov 3.5 M€ Hypernuclei ( read out electronics,micro tracker) 2.0 M€ Varia (e.g. refurbishing of forward detector parts) 1.9 M€ Trigger 1.5 M€ Infrastructure 2.0 M€ Contingency 2.0 M€ Sum 30.9 M€