1. Basic starting point
New tracker layers on the timescale of the first 5 years of running are a sensible first step
Contained in the volume from pixel layer 0 to 4
Need to use/reuse service space for pixels
Questions for R&D
Single layers or a complete replacement?
New sensor geometry and/or technology?
Small strips?
What features in the electronics to make first steps towards using these layers in L1?
Seeding vs correlation
Be on the road maps at the right levels and at timescales
To assist, already agreed CMS peer-review scheme
Main lines identified so far
Tracker & Trigger
Microelectronics and Power
Optoelectronics & data architectures
Merge at early stage into system(s)
SLHC Meeting - Frascati 24 Nov 2005
Fabrizio Palla INFN Pisa

2. Cost & Power estimate for new Tracker
Pix Sys #1 : layers
330 mW/cm2
High f pix SFr/cm2
Pix Sys #2 : layers
130 mW/cm2
Large pix SFr/cm2
Pix Sys #3 : layers
45 mW/cm2
Macro pix SFr/cm2
Eta =1.4  Area = 18.3 m2
Mechanics etc. not in costs!
Strip detector ~25 mW/cm2
SLHC Meeting - Frascati 24 Nov 2005
Fabrizio Palla INFN Pisa

3. Longer term R&D Power requires major effort & new ideas
Chip voltages reduce with technology evolution, currents may (??), but number of channels will not
Need to bring increased total currents through volumes which can’t expand
Material budget should not increase
R&D and qualification time is underestimated
Reduce the number of module types
Increase automation of assembly
Large systems are hard to build
Qualification must be taken seriously
True industrial production is likely to be required
Sensors are one of many issues
Any new material technology must be large-scale commercial within ~5 years
Electronic technology evolution will bring benefits
and also more complexity and much difficult work
SLHC Meeting - Frascati 24 Nov 2005
Fabrizio Palla INFN Pisa

4. Strategy
Is the right strategy R&D followed by request for complete new tracker?
Alternative could be upgrade…
..by installation of modest protoype system at tp = to + 5y
Less cost and lower risk
Less substantial case for support needed
More chance of resources, on short time scale
Allows trial of components or devices, which may still evolve
Technology investigations less popular with funding agencies than physics experiments
Human time-scale
Might be possible to react to LHC conditions, either machine, experiment or even discoveries
or to convince reviewers & funders…
May be complete pixel system replacement ???
SLHC Meeting - Frascati 24 Nov 2005
Fabrizio Palla INFN Pisa