1. Extending Physics Capabilities of the PHENIX Detector with Calorimetry at Forward Rapidities Vasily Dzhordzhadze University of California, Riverside for PHENIX Collaboration 21st Workshop on Nuclear Dynamics Breckenridge, February 05-12, 2005

2. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics2 PHENIX Detector

3. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics3 RHIC Executive Summary Energy densities: Maximum dE t /d  600 GeV at mid rapidity -> Initial  > 5 GeV/fm 3 >  cr Elliptical flow: Strong elliptical flow v 2 consistent with short thermalization times  0 ~ 1 fm/c Soft particle spectra: shapes & and yields consistent with hydrodynamic source emission. Particle ratios consistent with chemically equilibrated system before hadronization Hard particle spectra: strong p T suppression in central A+A (relaive to pp,pA & pQCD) consistent with final-state partonic energy loss in dense system: dN g /dy~1100 Intermediate p T spectra: Enhanced baryon yields & v2 (compared to meson) consistent with quark recombination mechanisms in a thermal and dense matter All observations are consistent with formation of thermalized strongly interacting matter in central Au+Au collisions

4. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics4 The Challenges to the Next Decade Move from exploration of new matter formed in A+A collisions to study of its property Accelerate progress in the developing spin program Upgrade Detectors: Increase acceptance, Implement vertex tracking, Implement jet measurment Upgrade RHIC: X40 increase Luminosity PHENIX central arms : 90 0 in azimuth and |  |<0.35 PHENIX muon arms : full azimuth coverage and 1.2< |  |<2.4

5. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics5 Upgrades to PHENIX Enhanced PID: TRD-East (x) Aerogel/TOF West (x) Vertex Spectrometer: Flexible Magnetic Field (x) Silicon vertex tracker TPC/HBD/GEM Forward Spectrometers New muon trigger chambers Forward silicon detectors Forward Nosecone calorimeters pA centrality detectors Very forward hadron calorimeter(x) DAQ/Trigger

6. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics6 PHENIX Forward Muon Upgrade presented by Xie Wei at this Workshop

7. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics7 Problems: -only 40 cm apart from collision point … -only 20 cm of space is available … and then …3.5 Labs of dead material downstream Layout: PHENIX forward spectrometers FST

8. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics8 Goals for the W-Si Nosecone Calorimeter Precision measurement of the EM showers Effective  0 discrimination Good  hadron separation Jet finding and coarse jet energy measurement Ability of fast triggering Nosecone coverage : full (360 0 ) in azimuth and 0.9<|  |<3.5

9. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics9 Existing Technology Today: PAMELA

10. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics10 e + e –  ZH, Z   at  s=500 GeV HCAL COIL ECAL Structure 1 Structure 2 Structure 3 62 mm Silicon wafers with 6×6 pads (10×10 mm 2 ) 62 mm 200mm 360mm LAL,LLR,LPC,PICM Imperial College, UCL, Cambridge, Birmingham, Manchester, RAL ITEP,IHEP,MSU Prague (IOP-ASCR) SNU,KNU CALICE ECAL 360mm Future: TESLA / CALICE

11. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics11 “coarse” (leakage) compartment “fine” (electromagnetic) compartment  0 /  identifier (Si strip layers) Photon converter section Shower max section section Si pad sensor layers Si pad sensor layers Tungsten absorber (16 mm) Tungsten absorber (2.5 mm) Ideas

12. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics12 front view side view 40 cm 20 cm  /  0 identifier EM hadronic Incoming electron (10GeV)  First 8.5cm: 16 layers of Tungsten (2.5 mm), Si(0.3 mm), G10(0.8 mm), Kapton (0.2 mm) and Air(1.2 mm). G10(0.8 mm), Kapton (0.2 mm) and Air(1.2 mm). –After first 6 layers there is a 0.5mm thick double layer of Si,G10,Kapton,Air (this is the  /  0 identifier).  Second half has a 6 layers with same sequence of materials, only thickness of Tungsten 16 mm. 10 GeV electron

13. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics13 Resolution for 1,5,10,40 GeV electron 1 1 5 10 40

14. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics14 e  10 GeV Electromagnetic shower measurements Expected Performance E 1/2  ~ 20%*sqrt(e)

15. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics15  2 Concept of Pion Rejection  2 =  (E i -E e ) 2 /  2 i i =1,3 22

16. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics16 Multiplicity per event Hadronic shower rejection  +, 40 GeV/c Expected Performance 100 K Simulated 4.5 K Selected Momentum GeV/c

17. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics17 Pion Rejection Momentum GeV/c

18. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics18 Jets Expected Performance

19. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics19 Digitizer Boards NCC readout location on the surface of magnet pole Central tracking communication lines Living Together …

20. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics20 ItemTotal W1.8 t Si (calorimeter)14 m 2 Si (  -  0 identifier)1.15 m 2 Readout units (calorimeter)288 Readout units (  -  0 identifier)24 Sensors (16 pixels)3776 SVX448 Digitization (subtowers)8448 NCC Mechanical Concept

21. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics21 receiverdigitizer Delay/ event buffers Smart DCM’s NCC L1 trigger board Global Trigger Sums Digitize signal as early as possible Generate low level trigger sums from the reduced bit ADC output locally Generate regional triggers locally receiverdigitizer Delay/ event buffers Trigger NCC Readout Concept (Chi)

22. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics22 4” High resistive wafer : 5 K  cm Thickness : 300 microns  3 % Tile side : 62.0 + 0.0 - 0.1 mm - 0.1 mm Guard ring In Silicone ~80 e-h pairs / micron  24000 e - /MiP Capacitance : ~40 pF Leakage current : 5 – 15 nA Full depletion bias : ~100 V Nominal operating bias : 200 V One wafer is a Matrix of 4 x 4 pixels of 2.25 cm 2. Important point : manufacturing must be as simple as possible to be near of what could be the real production for full scale detector in order to : Keep lower price (a minimum of step during processing) Low rate of rejected processed wafer good reliability and large robustness Sensors

23. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics23 Flex Cable Readout unit Si Sensor 256 analog lines Interconnect board PA board -This is the calorimeter – all pads in the subtower are contributing to signal; -Noise budget is set by physics: better is an enemy of the good; NCC Signal packaging Concept

24. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics24 Dynamic range [GeV]~100Kinematical limit MIP signal in a single Si layer (e)24k~300 mkm Si MIP signal in a subtower (e)144k-240k6 to 10 Si layers Max. charge per event in a subtower(e) 2.1 10 8 or ~ 40 pC50 GeV deposition, 1.7% sampling fraction Dynamic range>10000 MIP >1000 MIP 10 MIP 10 is the signal summed up over all contributing layers (10 layers max) Underlying event contribution can be neglected even in the central AuAu collisions Readout: Dynamic Range

25. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics25 CompartmentIIIIII Sampling layers6106 Sampling fraction (%)1.7 0.26 MIP energy loss [MeV]4269270 MIP energy loss in Si [MeV]0.71.20.7 Pad capacitance [pF]80 Trace capacitance [pF]10-45 10-55 Tower capacitance [pF]540-780900-1300540-900 Energy range of interest [GeV]0.5 – 50 Intrinsic energy resolution (em showers) [GeV] 0.4-1.5 Noise limit10 MeV15 MeV100 MeV ENC budget [MeV]0.150.20.15 ENC budget [electrons]40 k50 k40 k Readout: Noise Budget

26. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics26 Classical CSA followed by 4-th order shaper was modelled with PSPICE; Rise time and shaping time were optimized to achieve optimum noise performance for any given base-to-base (1% level) pulse length on the ADC input; 40k limit PYTHIA: the probability for tower to receive a direct hit in the pp minimum bias event is ~3% GEANT Shower spreading results in the tower occupancy increased to 10% Base line restoration in 300 ns Readout: Base restoration and signal shaping

27. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics27 2004 2005 2006 2007 2008 2009 …. pp 5+1 5+10 5+11 0 5+9  156pb -1 √s= ……………………….. 200 GeV ………………….........| P= 0.45 0.5 0.7 …………………………………………. Inclusive hadrons Charm Physics direct photons Jets W-physics A LL (hadrons)A LL (charm) A LL (γ) A L (W) L= 6x10 30 cm -2 s -1 8x10 31 cm -2 s -1 Schedule

28. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics28 Ongoing R&D program is funded by UCR (R.Seto) and BNL (PHENIX Upgrade Funds) –Prototype pad-sensors, analog cables, readout units, front-end - MSU; strip-sensors for the g/p 0 identifier – Prague. Backup solution - from earlier project in Trieste; Readout for g/p0 identifier – SVX4 (Prague). Backup solution – same as in the calorimetric layers (MSU). Preamplifier (decision for CDR) –New device developed at BNL; –Upgrade to CR3A developed as part of R&D program in Trieste – preferred but ….. ; –Upgrade to preamp developed as part of TESLA/CALICE program – under investigation; –New device developed in collaboration between MEPhI/MSU/BNL – proposal exists; –Just new device (dreams exist). Mechanics of the future detector (prototype and CDR) –Work started in Dubna (A.Litvinenko). Digital readout (CDR) –New group from Dubna (S.Bazylev) will be helping with CDR Near Term Priorities

29. 02/11/2005 V.Dzhordzhadze 21st Winter Workshop on Nyclear Dynamics29 o PHENIX has great plans for a program of new physics aimed to study nuclear effects in partonic structure functions down to a very small partonic momenta. It spans the whole range of pp (including polarized), pA and dA collisions at RHIC. o Integrated forward spectrometer upgrade is the precondition for PHENIX to stay competitive in this new field of physics. o We have technical solutions which match physics and present an excellent opportunity for new groups both in physics and instrumentation! Summary