E.Kistenev Silicon W Calorimeters for the PHENIX Forward Upgrade
Event characterization detectors in middle PHENIX today Two central arms for measuring hadrons, photons and electrons Two forward arms for measuring muons
How PHENIX works Spectators 1-15% 5-1% -5% Participants South Muon Magnet Central Magnet North Muon Magnet Peripheral Central ZDC South MuID MuTr BB MVD ZDC North MuID South Blick von der Seite North Centrality selection : Sum of Beam-Beam Counter (BBC, η =3~) and energy of Zero-degree calorimeter (ZDC) Extracted N coll and N part based on Glauber model.
History lessons and future directions The devil in the details: PHENIX needs luminosity, acceptance and sensitivity to right probes -PHENIX contribution to sqgp discovery heavily relied on p and direct g measurements in central electromagnetic calorimeters: build on success extend acceptance for electromagnetic probes; -All experiments at RHIC measure jets only indirectly via leading particles. Include direct jet measurements whenever possible; -Use unique feature of PHENIX: muon spectrometer Optimal strategy for upgrade: Convert PHENIX Forward Muon System into PHENIX Forward Spectrometer
PHENIX Upgrade
Constrains -space cm from collision vertex cm total depth -no tracking upstream (momentum and charge unknown) Goals -Reasonable energy resolution for em probes; -Best possible separation between em and hadronic signals -Ability to reconstruct p s to ~3 GeV/c -Jet identification and cone energy measurements for lepton tagging and isolation testing
NCC tracking calorimeter Parameter Value Comment Distance from collision vertex Radial coverage Geometrical depth cm 5 cm ~19 cm Absorber W Lrad or 1.6 Labs Readout Calorimeter Preshower detector (PS) Si pads (15x15 mm) and pixeleted strips (..5x.5 mm pixels grouped into 6 mm long strips) EMC(1 sampling cells: 3mm W +.5 mm readout) longitudinally structured into two identical nonprojective sections. Leakage(6 sampling cells: 15 mm W +.5 mm readout) Lrad W converter followed by a stripixel layer (.5 mm strips) with -d readout Shower max detector (SMD) In between two EM sections at ~ 7 Lrad depth. Stripixel layer (.5 mm strips) with -d readout Multiple scattering in NCC combined with Fe magnet pole Expected EM energy resolution % Expected jet energy resolution % Two showers resolved at in calorimeter ~/sqrt(e) ~1/sqrt(E) 3 cm 133 MeV To compare with 16 MeV in the existing configuration with Cu NoseCone in preshower mm In simulation effective for shower separation down to mm in shower max. mm
-d pixilated strip sensors Pad-structured sensors EM Segments Hadronic Segment strips 3 GeV/c π in NCC towers
Design optimization -Total depth fixed to 19 cm -Three segments (EM1/EM/Hadronic) -Plate thickness in EM segments varied from mm up in steps of.5 mm -Plate thickness in Had segment is whatever fits the total depth limit
Design optimization: electromagnetic vs hadronic -correlations between plate thicknesses in em and hadronic segments push towards thicker plates in em segments; -Optimal em resolution and discrimination power is reached for W plates in em segments 3 mm or thicker; -For a fixed total calorimeter depth there could be advantages to using Pb instead of W in hadronic segment.
π > > γ γ 5.3 GeV/c π > > γ γ 9.5 GeV/c
P recognition/reconstruction Select clusters of amplitudes in all segments; Combine energy ordered clusters from different segments into tracks Define regions of interest in PS and SM foe every cluster (cluster energy dependent); Discount clusters with only one hit in PS, for multiple hits in PS compute separation between two hottest hits; Select two clusters in SM (constrained by hit separation in PS) and fit energy ratio; Use total track energy, hit separation from PS and energy ratio from SM to compute effective mass; Retain those within p window as p candidates, build effective mass combinatorics among everything else.
Claims to substantiate Single-particle (π and e) simulation in NCC
π losses today π efficiency today
R&D -5: BNL-MSU-UCR-RIKEN DC coupled, pad structured - completed AC coupled, pad structued - completed DC coupled, r-biased, pad structured at ELMA and ON Semi StriPixels 5 µ
Depletion voltage for 3 mkm sesors.7.6.5 1/C^..3..1 Total dark current, na Series1 Series 6 5 6 8 1 1 Bias voltage 3 1 I vs V 5 1 15 5 Bias voltage, V
7 Current and Capacitance at 5V 6 5 Current, pa Capacitance, nf 3 1 1 3 5 6 7 8 9 1 11 1 13 1 15 16 Pad number
We can really do it
Eneregy resolution Positron run 39 Event 3 3 1 1 Plane 1 3 1 Plane 3 35 3 Positron run 39 17. / 11 P1 36.5 P 39. P3 373.8 P -163. P5.1118 P6.858E-5 P7 -.8773E-8 P8.897E-1 6 5 1 1 Plane 3 3 1 Plane 3 15 1 1 15 1 5 5 5 3 1 Plane 5 3 1 Plane 6 6 8 1 Amplitude sum
Pointing resolution Position resolution [cm].6.5..3..1.5 5 7.5 1 1.5 15 17.5.5 5 Depth at the segment center [X ] Events/θ 9 X 8 7 σ = 6.5 6 5 3 1-5 -5 5 5 [mrad] 8 Y 7 6 σ = 6.6 5 3 1-5 -5 5 5 [mrad]
R&D to complete 6-7 R&D 6-7: Development 6(k$) 7(k$) Total(k$) Funding source Pxilated strip sensors (StriPixels) 6,3 6,3 RIKEN R&D Pad-structured readout units 18,565 18,565 DOE Generic R&D Strip-structured readout units 5, 15,, RIKEN R&D Pad readout analog elecronics 15, 15, RIKEN R&D Pad readout digital electronics 3, 5,813 8,813 DOE Generic R&D StriPixel readout electronics, 8,5 1,5 RIKEN R&D R&D 6-7: Design and Prototyping Mechanical Design 6, 6, UCR R&D Pad-structured sensors 7,,531 9,531 RIKEN R&D Pad-structured ROU's 5, 19,33,33 DOE Generic R&D Electronics for pad-structured layers 1, 7,5 37,5 DOE Generic R&D Pixilated strip sensors (StriPixels) 1,5 1,5 DOE Generic R&D StriPixel ROU's and electronics 18,185 18,185 DOE Generic R&D Mechanical Structure 5, 8,85 13,85 DOE Generic R&D Testing (bench and Test beam) 17,38 17,38 DOE Generic R&D 6-7 request to DOE 1,565 17,7 18,81 6-7 request to RIKEN 15,3 6,981 166,81 Others (UCR) 6, 6,
Project at a glance Funding Source Base cost Contingency [%] Overhead [%] Cost to Project DOE Generic R&D Funds $1,5 31 17.5 $16,33 RIKEN R&D Funds $138,5 1 $15,5 UCR R&D Funds $5, $6, MSU R&D Funds $ $ JINR (Dubna, Russia) R&D Funds $ $ Czech group R&D Funds $ $ Korean group R&D funds $ $ DOE Construction Funds $,31,63 3 17.5 $3,83,5 Collaboration construction funds $,386,63 $3,6,8 NCC Project $5,189,759 37 $8,31,3
Summary There is a lot of momentum Next two years are To substantiate the performance claims; To accumulate data to build analysis chain; To finish design and test production chain; Three years for construction project are tough but feasible. We can get to the physics of saturation in 1.