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Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
DCH R&D- Italy
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
DCH: What We WantI. A lighter structure, all in Carbon Fiber (CF)
because we know this can be done investigate possible options
II. A faster detector, with faster R.O. electronicsbecause we know life will be tougher @ SuperB
Simulations, R&D studies with prototypes
III. Lighter FEE (including shielding & cooling)because we may want to place detectors behind the DCH backward endplate now
DCH: What We KnowThe BABAR DCH worked well for almost 10 years
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Spherical Carbon-Fiber end-plates PRELIMINARY!
Minimize thickness at fixed deformation
Thickness O(4mm), or 0.015 X0
compare 0.13 X0 in BABAR
Convex shape could fit bettere.g. with forward PID device
Convex
Concave
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
A possible occupancy issue
High background rates expected in the forward region to be quantified with detailed simulations
high occupancy in innermost cell layers, possibly tamed with: tapered endplates screening the sense wire
discussed in next slides
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Screening the sense wire Prevent electron multiplication in selected regions along sense wire
To test the idea: we built drift tubes, with part of the sense wire ‘screened’.
sense wire
“good physics track”
plastic collar
ionization in very forward region
30 m W (Au-plated) wire
80 m inner Ø,120 m outer Ø~10cm long peek tube
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Scan the wire with a 90Sr source: Current vs. source position
Free wire
Start of plastic tube
Further down the plastic tube End plug “A”
No source
End plug “B”
Preliminary tests indicate that screening the sense wire works as expected
e.g. current drops to half the value when 90Sr source exactly placed beginning of screen
Next step is measuring charge and time-to-distance with MIPs. Need also to consider carefully:
Long-term behavior/aging (Modify the wire diameter instead?) Stringing issues
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Re-commissioning of DCH prototype Started re-commissioning of small
DCH prototype Wires OK Electronics OK Gas tightness OK
Read out few channels Signals look good Need more electronics to read out all
underway Can easily replace bolted end plates
with new ones with different cell geometries
30-May-2008 Elba Super-B Workshop 7
Re-commissioning of precision tracker
First pass with coarse space-time relations achieved resolution of 120 m
on-board electronics for all 52 channels being designed, to be ready after Summer
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Summary and Outlook
Evaluating different solutions with an all-Carbon-Fiber structure
Perform test of wire screening with MIP’s Completing set up of all necessary tools for our R&D plan Proceed with Garfield simulations of various cell
geometries to select few solutions to test Build new prototype’s end plates with different cell
geometry solutions Prepare for test beam
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
PID R&D- USA
• Whether there is, or is NOT, a forward PID system depends on there being a clear, strong physics case.
• If there is such a case, the technology chosen for a forward PID system depends on
• # physics requirements on which momentum region is most useful;
• # photo-detector choice;• # engineering issues;• # background resistance;• # cost.• Adequate backward PID may be obtained by a fast backward EMC instead of
a separate detector. This option should be carefully explored• Ongoing R & D includes work on Photon detectors, fast timing, and Aerogel
radiators• Even without the EC PID devices, major effort is required to design and
construct the new SOB and DIRC photon detection system.• New groups/individuals interested in PID design and R&D are strongly
encouraged to join the effort.• See JJV talk
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
EMC R&D- USA
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
IFR R&D- Italy
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
IFR: R&D statusIFR: R&D status
adc channels
1 p.e.2 p.e.
pedestal
ADC spectrum for MPPC
1.5 p.e. Cut
• Average number of p.e.: ~ 9 at maximum distance (~4m)• Efficiency better that 95% •Detailed study of SiPM and MPPC signal characteristics: a lot has been done, still more to do
Present baseline configuration: Scintillator: 1.5cm thick with embedded hole /surface grooveFiber: One Saint-Gobain BCF92 1.0 mm diameter Readout: Geiger mode APDs from Hamamatsu or IRST-FBK
cou
nts
Distance ~200 cmsigma 1.3 ns
Distance ~200 cmsigma 1.8 nsMPPCMPPCSiPMSiPM
The time resolution is < 2 ns and is better with SiPM (IRST) than with MPPC (Hamamatsu)
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Simulation
A first description of the IFR is ready for Geant4 simulation.
First events have been generated and analyzed for consistency checks.
Further validation will be done with more statistics.
• Need full reconstruction to obtain a fine detector optimization.• The plan is to use the BaBar framework + SuperB background events.
• Fast simulation: plan to release a preliminary version useful for physics by the end of June• Then improve the parameterization according to the detector optimization.
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
SuperB IFR path to TDRSuperB IFR path to TDR
For the TDR:For the TDR:Simulation Simulation requested detector performance requested detector performance Detector DesignDetector Design
ScintillatorScintillatorFiberFiberPhotodetector: time resolution, afterpulses, noise, Photodetector: time resolution, afterpulses, noise, radiation hardnessradiation hardnessElectronics + DAQElectronics + DAQPreliminary Detector Layout, including preliminary Preliminary Detector Layout, including preliminary mechanics/detector integration (Summer09)mechanics/detector integration (Summer09)
Prototype Design Prototype Design Construction (starting Sept09) Construction (starting Sept09)Prototype Beam Test (Spring 2010) Prototype Beam Test (Spring 2010) Final Layout for TDR (Summer/Fall 2010) Final Layout for TDR (Summer/Fall 2010)
At present:At present: Ferrara, Padova, Roma1 InstitutionsFerrara, Padova, Roma1 Institutions
A lot of work to be done for TDR,A lot of work to be done for TDR, additional forces very helpful and welcome!additional forces very helpful and welcome!
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Computing Developments
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Computing Developments
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Computing Developments since Elba
• Summer!
• Formation of the computing planning group• - Gregory Dubois-Felsman (chair)• - David Brown• - Peter Elmer• - Fabrizio Bianchi• - Roberto Stroili• - Mauro Morandin (ex-officio)
• Still need contributions from detector community
• Status report at R&D meeting tomorrow
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Summary of BaBar Reuse, Transport,& SuperB Home-Bill
BaBar Disassembly starts soon; lasts ~4 years. Components for re-use in SuperB, namely the EMC Barrel, DIRC
bar boxes and support structure, and coil and cryostat with support systems, are removed from the barrel steel for move to SuperB in mid-2010.
EMC Barrel transfer Tor Vergata: hope to ship as a unit, preferably by air. Engineering is needed to determine if this is feasible. If not, disassembly of the barrel down to 280 modules (each typically 21 crystals) and support cylinder structures will add considerable time until the installation of the EMC Barrel into SuperB. Additional environmentally conditioned assembly space would be required in the disassembly case.
DIRC transport as a single structure is not practical: structures are too big and require vertical transport due to bar box construction. It is best if bar boxes are removed and shipped separately.
Magnet cryostat has been shipped from Ansaldo to SLAC by air, providing proof of principle for return to Italy.
Steel will arrive somewhat later, by boat, after the sextants are separated from each other and split in two.
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
BaBar Reuse, Transport, SuperB Home
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
BaBar Reuse, Transport, SuperB Home Site of SuperB hall will provide a spacious home,
properly sized from experience at IR2, for these systems.
Coexistence with the embedded accelerator final focus cryostats promises to be challenging.
Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008
Summary We are beginning to develop beyond our conceptual design
(as presented in the SuperB CDR) for the SuperB detector, based on BaBar.
Substantial Planning, Design, and Physics and Detector simulation studies are needed to continue the process.The individual Subsystems need R&D and appropriate software tools to develop the best detector components within this overall design.
Impressive progress on software and simulation tools We hope to move to a high quality technical design and TDR
within ~ 2 years. All areas need more people. Many opportunities exist
to get (even more?) involved in the detector, including subsystem R&D and general detector systems, software, physics simulation, and design.
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