Prototyping Status and Plans at TRIUMF

Christopher Hearty!University of British Columbia/IPP!

17-Mar-2010!

1!

Goals

 Establish benefits and practicality of cluster counting for particle identification and tracking.!

 Provide a test bed for testing gases and electronics.!

2!

Overview

 32 active cells plus border cells & guard wire! Square 9 mm half-cell.!

» other options are possible! 2700 mm length to check impact of

transmission, attenuation, impedance matching. ! Test with cosmic rays, possibly with magnet,

and in test beam.!

3!

Design

 Aluminum endplates with holes suitable for BaBar feedthroughs!

 Outer cylinder is Copper-clad Mylar ! Two 75 mm x 25 mm U-channels for

mechanical support! Design is new and evolving; input welcome. !

4!

Hole diameters:!sense: 4.5 +0.025 -0.00 mm!field: 2.5 +0.025 -0.00 mm! 5!

6!

7!

Brackets to hold the prototype at various angles!

Garfield

 Obtain time-to-distance relations; verify edge and center cells are similar for appropriate guard voltage.!

 Select field wire diameter to obtain <20 kV/cm !» correct diameter is probably not essential for

prototype! Non-uniformities; entrance angle effects. !

8!

9!

Drift lines and isochrones (50ns) for different cells!

10!

Difference in x(t) between specified cell and center cell as a function of guard wire voltage. Best results if guard wire voltage = 0.!

11!

Entrance angle corrections!Drift time vs drift distance for tracks at specified entrance angle, DOCA = 0!

Quite large changes in time-to-distance relationship for relatively small changes in angle. I am tempted to look at a hex cell for this prototype.!

Drift distance (cm)!

Drif

t tim

e (n

s)!

Construction

 This is BaBar-like construction, not SuperB type construction. Essentially all components are from BaBar:!» 20 um gold-coated tungsten wire!» 80um and 120um gold-coated aluminum!» sense, field, and guard-wire feedthroughs!» crimping tools!

 Aim to start construction late April. !

12!

Readout Boards

 Need readout boards to connect HV and preamps to sense wires. !

 Quite complicated objects for BaBar, but we will simplify things a bit by applying guard voltages at non-readout end. !

 Grant Sheffer will design, but needs input from cell layout and amplifier. !» hypertronic connectors available from BaBar.!

13!

14!

Preamp/Shaper

 Amplifier matches impedance of cell (~400 ohms for BaBar) and amplifies and shapes signal.!

 We need high bandwidth to preserve timing resolution for cluster counting. 500 MHz? Implies rise time of ~0.3 ns. !» was 200 MHz for BaBar chip. !

 Jean-Pierre Martin (U. Montreal) will work on solution. Timescale not yet clear. !

15!

16!

input impedance adjusted via Q1CON input!

BaBar Preamp!Chip also included shaping, discrimination, and calibration!

Digitization

  Initially, digitize waveform with minimal processing. !

 Options:!» high-speed scope (1 GHz bandwidth)!» CAEN switched capacitor array V1729A (300 MHz

bandwidth)!» CAEN V1751 waveform digitizer or similar (500

MHz bandwidth)! CAEN units fit into standard TRIUMF DAQ;

scope is non-standard readout. !17!

18!

V1729A!

Waveform digitizers!

Gas System

 We are set up to mix gases. We can decide on desired mixture later, or try various mixtures. !

19!

Proposed Operations

 Aim for cosmic operation in August and September, test beam starting October.!

20!

 Solenoid is available for cosmic tests (too much material for beam), 0.7–1.0 T.!

M11 Beam line

 0.3–3 kHz of e+ / μ+ / π+ for 100 – 300 MeV/c; mostly protons for 300 – 420 MeV/c. Few cm beam spot.!

 TOF for ~10% of particles; could be improved.!

21!

Status of Resources

 NSERC has funded operations for prototypes and TDR (travel, students, 0.5 postdoc)!

 We have requested capital, mostly for readout electronics/scope. Will hear ~ April 1.!» we can borrow 12 channels of V1729A!

 TRIUMF has approved in principle support for prototyping and TDR (detector facility, engineering, design office). We have just submitted specific request for detector facility support. ! 22!

Draft Schedule

1 Concept Design:2 Prototype 40 days 3/1/1... R. Henderson[50%]

2 Design service boards 15 days 4/26/... 1;5 Grant Shaeffer

3 Fabrication of service boards 15 days 5/17/... 2 External: board prod.

4 Assemble/Test service boards 20 days 6/7/1... 3 Grant Shaeffer

5 design FE: preamps 15 days 4/5/1... Detec. R&D (Fabrice)

6 Develop Equip to test wire& crimp quality 20 days 4/5/1... Detec. Fac. technician

7 Construct. Prototype: machine endplate 10 days 5/17/... 2 Detec. Fac. machinist

8 Construct. Prototype: string chamber 15 days 5/31/... 6;7 Detec. Fac. technician

9 Complete Assembly of electronics & service bo... 10 days 7/5/1... 4;8;5 Detec. Fac. technician

10 Assemble cosmic ray setup+gas system det. fac. 15 days 4/5/1... Detec. Fac. technician

11 Supervision of assembly 50 days 3/10/... W. Faszer[10%]

12 Install Strovink magnet in det. fac. 20 days 3/10/... Magnet group[50%]

13 Assemble DAQ system in det. fac. 10 days 5/3/1... DAQ group

14 Take&Analyze cosmic data w Magnet in Det. Fac. 60 days 7/19/... 9;1... Physicists

15 Move test setup, excluding magnetc, to M11 16 days 10/11... 14 Detec. Fac. technician

16 Take &Analyze M11 test beam data with proto. 60 days 11/2/... 15 Physicists

17 Gas system and DAQ for wire aging studies 15 days 5/3/1... Detec. Fac. technician

18 Design & fab. single-cell chambers for gas stu... 30 days 5/3/1... W. Faszer

19 Taking and Analyzing aging data 100 d... 6/14/... 17;18 Physicists

20 Conceptual Design of full DCH for TDR 60 days 9/27/... 1 R. Henderson

21 Conceptual Design of Full DCH for TDR 40 days 1/25/... 16;... R. Henderson

22 Engineering for TDR 40 days 3/22/... 21 Naimat Khan

23 Technical Design of full DCH for TDR 20 days 1/3/1... 20 UVic design office

24 Design of full DCH for TDR 60 days 3/22/... 21 R. Henderson

Name Duration Start Pred... Resource NamesF M A M J J

Half 2, 2010

A S O N D J

Half 1, 2011

F M A M J J

Half 2, 2011

R. Henderson[50%]

Grant Shaeffer

External: board prod.

Grant Shaeffer

Detec. R&D (Fabrice)

Detec. Fac. technician

Detec. Fac. machinist

Detec. Fac. technician

Detec. Fac. technician

Detec. Fac. technician

W. Faszer[10%]

Magnet group[50%]

DAQ group

Physicists

Detec. Fac. technician

Physicists

Detec. Fac. technician

W. Faszer

Physicists

R. Henderson

R. Henderson

Naimat Khan

UVic design office

R. Henderson

SuperB DCH 2010Prototype&TDR

23!

Aging

 We are planning aging tests following Boyarski!» single cell tests!

 Test proposed gas and materials!»  in particular, samples of

bare aluminum field wires! Need funding for bare

wire, hot source, gases. !24!

size of single electron peak increases due to Malter effect as chamber ages!

A. M. Boyarski, Nucl. Instr. Meth. A 535, 632 (2004)!