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points discussed in the review
Dear all,
Elton and I tried to summarize the points made in the review. Please find
the list below, I'm sure we missed some, please drop me a mail, I will add
missed points to the list and circulate it ones more. So we have a list we
can tick of things.
Of course as soon as we have the full recommendations we will circulate
them.
Cheers
elke and Elton
CDC:
====
o strength of CDC is that straws support the weight of the wires
---> end plate can be thin, but can we make it thinner? composite?
- Need details of construction and alignment worked out and written
down including cost details. i
-- Should have a precise as-built alignment which can be used as a start
for tracking.
- stereo layers closer to the beam
-- does it help for z-resolution
-- is it possible if not why
-- is +/- 6^o the best stereo angle
-- readout the closest ones out with TDC if rate is a problem for dE/dx
-- axial layers at smaller radii?
-- axial layers then all stereo?
- why making each strew gas tight and not have one gas tight plenum at the
down stream end
-- would also reduce material, no plugs
-- would the gas flow be enough
- rate impact on dE/dx
- is humidity a problem
Magnetic field:
===============
- Need "enough points to verify".
- Should put together a short note including
-- number and placement of Hall probes
-- procedures for checking field when magnet is first energized
-- checking of, e.g. magnetic field axis.
---> checks with a distorted field-map in the MC what influence exist
on tracking
FDC:
====
- One more round of thinking cathode drift chambers are the
optimal solution
-- micro-drift chambers or ....?
- options for reducing material in existing design:
-- replace Cu with Al?
-- Arguments against Al: PC board manufacturers "won't touch it", higher
attenuation, cannot gold flash to Al reliably, cannot solder to it.
-- Lithography techniques?
-- eliminating rohacell from structure?
-- issue here is distortion in planes due to stretching.
-- remove rohacell from beam hole / dead strip area
--> plan to prototype with and without rohacell and measure differences
- reduce number of layers are 3 enough
- reduce the 1 cm gap?
-- this reduces sensitivity to B field.
-- gap driven by connector thickness, can we bring out the signal by
flex foils
- sensitivity to B-field
-- gas mixture could we run with a helium mixture
tracking and simulations:
=========================
o major recommendation is to make the simulation and patter recognition a
priority
-- kalman filter
-- revisit length of CDC with full geant-MC
o manpower
General:
=========
- Effect on PWA leakage
-- contributions from conversions of particle interactions in detector material?
false signals?
- Generally problems in Hall B and D are very similar.
-- Commonalities include technical and engineering resources which should be
exploited by both groups.
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