Transcript No Slide Title

ISL
David Stuart,
UC Santa Barbara
May 11, 2006
ISL
Formerly known as
Intermediate Radius Silicon
David Stuart,
UC Santa Barbara
May 11, 2006
I’ll review the motivation
for the detector
and give a tour of its
design and construction
The motivation is best shown by looking at an
event display from Run 1.
The motivation is best shown by looking at an
event display from Run 1.
The motivation is best shown by looking at an
event display from Run 1.
Tracks are obviously missed and obviously easy to find.
Actual size
Unused hits from:
1. Low pT
2.  > 1
Using forward silicon hits in Run 1
1. Stand-alone silicon pattern recognition
• Fit for f0, d0, pT (curvature)
with 4 hits, <=1 dof.
• It worked, but was limited by
• lever arm (L2)
• Too few hits
• Poor curvature resolution degraded
impact parameter resolution
• 4% relative increase in b-tagging for top
Using forward silicon hits in Run 1
2. Calorimeter-seeded tracking for electrons
i.e., Phoenix
eeggET event
eeggET event
ISL designed to extend lever arm
ISL
SVXII
L00
SVX’ (Run 1)
Design goals
Fine granularity at large radius for
Low occupancy
typical jet has ~10 tracks in a Df<0.2 cone, covers 1000 channels
Resolution and lever arm (BL2)
100 m pitch = 30 m resolution sufficient for
Negligible effect on d0 resolution
Pointing into COT
< hit resolution at high pT
2trk
< hit width at low pT
COT
res
Portcard scattering is a real complication
Design requirements
Big (5 m2)
Cheap
Fast
Design requirements
Big (5 m2)  simple
Cheap  simple
Fast  simple
Piggybacking on SVX-II infrastructure important
Sensor Design
Big- used max possible sensor size per wafer.
HPK only had 4” wafers
Micron had 6”, and they were cheaper
(in both senses of the word).
Layer 6 built with HPK at Fermilab
Layer 7 built with Micron at Pisa
 Different geometries, mechanics, & quality
Readout Hybrid
Double sided and spacious
Pitch adapter
Transceiver
Half ladder
Full ladder
Ganging
Not in trigger, but don’t preclude, so r-phi read first.
16 chips total--max FIB can handle.
Note up-down reverses hall effect and readout direction.
Joel dropped them in place
Supported by carbon fiber spaceframe
Containing cable and cooling
and gang card mounts
Notable differences from SVXII
• Because rad damage is less of a concern, and no direct
silicon heating
– ISL operates ~10 deg warmer than SVXII
• Layer 6 has the implant on the z-side
• IB0,1,4,5 (forward region)
– L0,L2,L4 are layer seven (Micron sensors)
– L1,L3 are layer six (Hamamatsu sensors)
• IB2,3 (central region)
– Everything is layer six
• Within a given layer, IBxWyLz, y and z denote phi position
of ganged readout pair
Recall Design goals
• Forward tracking
Recall Design goals
• Forward tracking  ?