DCH R&D- Italy

Blair Ratcliff, SLACUS R&D Meeting, Sept. 3, 2008

DCH R&D- Italy


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


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


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


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


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


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


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


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


EMC R&D- USA



IFR R&D- Italy


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)


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.


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!


Computing Developments


Computing Developments


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


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.


BaBar Reuse, Transport, SuperB Home


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.


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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DCH R&D- Italy