SLHC Pixel Layout Studies S Dardin M GarciaSciveres

SLHC Pixel Layout Studies S. Dardin, M. Garcia-Sciveres, M. Gilchriese, N. Hartman LBNL November 4, 2008

Background and Goals • Studies shown here are simple, almost “lines on paper” • Have included some realism in lengths of staves and radial extent of disks based on module dimensions but don’t believe dimensions to the mm-level • Previous reports are worth looking at to understand evolution – see for example talks here 2

Assumptions • Minimum of four pixel hits • Cover | | ≤ 2. 5 for tracks |z| ≤ 10 cm (nominally 2 although needs to be confirmed as design of SLHC evolves) • Define “pixel-only volume” bounded by (short) strip detectors (R ≤ about 35 cm but final boundary TBD) and beam pipe at inner radius • Two pixel hits permanent • Two hits insertable from end/replaceable 3

June 2008 Layout 1 Drawn width represents tilt Modules both sides assumed here Common support shell Angle “End-of-disk card” Not shown Radius(cm) Fixed section Boundary of silicon strip tracker Insertable section Single-sided staves here “End-of-stave card” Arbitrary guess Z(cm) Insertion tube

• “Bent” stave to reduce material • Measurement mostly at larger R • Gap in coverage and bend? Relative X 0 June 2008 Layout 2 8 7 6 5 4 3 2 1 0 0 1 2 Pseudorapidity 3

Input to Project Office Models

Many Options Explored • These and more are described more here. 7

Monolithic insertable pixel options BOX Section Beam, single cooling circuit. I Section Beam, single cooling circuit. Buttable modules to avoid large gaps

Pixel Barrel Overall - Example Layer 0 1 2 3 Number Staves 15 15 32 40 Modules per Stave 32 28 32 32 Total Modules 480 420 1024 1280 Module Type Single Chip 4 Chip Active Edge 4 Chip Normal

Disk Examples • Hermetic by design (see local supports talk for how implemented) • Overlaps in R and Both sides One side 10

Push Outer Envelope • What is outer envelope? • Maintain space for support structure and services at outer radius. • This is tight if outer envelope is about 34 cm, based on current experience End-of-disk “cards” Same arbitrary area/module as for staves 11

More Outside Room • Reduce radius of outer layers by 2 cm • Reduce disk size • May allow exterior support structure and services routing or support from insertion tube and routing along it. 12

More Forward Hits • Possible to add more forward hits • Could keep all disks same and do this(not shown here but easy to imagine) • Of course could add disk also…. 13

My Comments • Staves are long(material? ) and disks are big. Need reality check from design and prototypes before expending too much effort on detailed layouts. • Nearing end of utility of simple layout studies (at least for engineering) • Obvious information needs – What is outer envelope of pixels? – What are the dimensions of end-of-stave and end-of-disk cards? – Insertion tube (only) or insertion+support outer layers? Stiffness and other requirements (it’s not so large in diameter) – Thermal requirements for this tube – Feedback from services and support envelopes => change layout • Time for some more detailed modeling with real engineering design input. 14