Some thoughts on Tracking System for Stage 1 HPS

Simon Kwan

Fermilab

09/19/2011

Krzysztof Piotrzkowski July 2011

Design Considerations• Based on the last three slides, we make the following

assumptions – Ready for installation in 2013/2014

– Four stations (2x2) at 240 m from IP5

– Each station has 4 pixel planes covering roughly 1cm x 3 cm

– Resolution per plane ~50 m (??)

– Would like to avoid large dead area near pocket window

– Use as much as possible parts from CMS pixel detector (sensor, ROC, optical links, DAQ etc)

– Use ~300m long optical fibers for signal/trigger/control transmission to/from CMS DAQ

– High and potential high fluence up to 1015 p/cm2/year (please confirm)

– Detector sitting in its own box and not in secondary vacuum

• If any of the above are not valid, please sing out loud

Other important considerations• Tracking group too small; needs help on getting resources

(money, expertise)

• R&D activities focused more on 3d sensors which would not be ready for 2013/2014

• Not difficult to come up with a design for the Technical Proposal but will there be interest amongst the collaborating groups to build such a system

– Stage II system will be very different (diversion of effort both in building and operating it)

– Rather limited physics reach

– Little synergy with CMS pixel upgrade

• CMS Pixel upgrade now plans to have a pilot system ready for 2014 (manpower, diversion of effort ……). Possible to combine effort with FP240 Tracker???

Pixel Modules (contd)

• Alternatively, we still have about 14 good sensor wafers that we could use (each wafer has two 2x3s and two 2x4s)

• Still has a number of the PSI46v2 ROC wafers and enough tested good VHDIs ~ 14 2x4s and 10 2x3s)

• Question is of course on bump bonding and re-start the plaquette production (time, money, resources etc but do-able)

CMS Pixel Modules• A 2x3 or 2x4 CMS FPIX plaquette could

be used for the plane

• Inventory:

Breakdown below 500V and more than 1% bad pixels per ROC -> acceptable?

About 6-8 each of the grade B 2x3 and 2x4s are not available any more (used in the Fermilab MTEST pixel telescope)

Will Johns July 2011

Station Design• Each plane could be tilted at 30 degree or more to minimize the dead

area near the pocket wall• Pixel size is 100x150 um and if resolution required is 50um, don’t need

x-measuring and y-measuring plane• It can be mounted on a carbon fiber with excellent thermal conductivity.

All planes will be sitting on a metal base plate with cooling lines inserted.

• Cooling can be implemented (may really be needed if the fluence is as high as claimed)

• Each plane will be connected by a short flat cable to a PCB which serves a pair of station. One TBM will be located on the PCB to orchestrate the readout.

• Power and signal/control will be provided to the ROCs through this PCB• Need to design the PCB (Station readout card) and the cable (pigtail)• Pigtail is about 60-70 cm long

Station readout• Pigtails will connect to a port card.

• Two pigtails per station

• The two stations on the same arm will be readout by the same port card

• Port card will house one Analog optohybrid ( 6 channels) and one DOH (for the ROC settings). It will also has the gatekeeper, delay25, TPLL etc. Pretty much like the current Port card for FPIX but needs a different yet simple redesign

• From the port card, long optical fibers will carry signal to/from the central CMS DAQ

• While details still have to be worked out, the proposed conceptual design should work and would need only minimal change to the DAQ and DCS software.

Will Johns July 2011