Layer 0 Installation and Commissioning

1
Layer 0 Installation and Commissioning
This talk will cover plans for pre-installation
work in the 2004 shutdown, final installation in
2005, and post-installation hardware
commissioning

• We want to maximize physics from the experiment
  minimal down time and efficient use of shutdowns
• The Fall 2004 shutdown is expected to be rather
  long (gt13 weeks) but manpower may be limited.
  The 2005 shutdown may be shorter.
• We wish to refurbish and reinstall the H disks so
  that we have close to 100 functionality in the
  remaining device. This could be done in 2004 but
  will be difficult in 2005
• We want to be sure that layer 0 can be installed
  safely and easily

2
Fall 2004 Plans

• We plan to install and operate a 4-hybrid SVX4
  string during the 2004 shutdown. This will allow
  us to test a mixed SVX2/4 readout system with the
  associated controls and download software. It
  will also test our grounding isolation scheme
  with new adapter cards
• Test operating the cooling system at lower
  temperature
• Reroute H disk cabling consistent with L0 scheme
• We are also considering removing and refurbishing
  the H disks. This depends mainly on personnel
  availability. If we do this we can also
• Photograph H-disk and support cylinder regions
• Survey installation clearances

3
Fall 2004 SVX4 String Infrastructure

• Moving counting house
• Weiner Power Supply
• VESDA/Cooling interlock chassis
• Cathedral
• Mini Fuse Panel
• Calorimeter Gap (Horseshoe)
• Adapter Card

Need to move 3 H disk cables 16C1 ? 10C1 16C2
? 24C2 17C2 ? 18C1
4
H Disk Refurbishment
This would involve removing the 4 disks,
producing two 100 disks and 2 poorer disks,
and reinstallation. The goal is to avoid effort
in the (shorter) 2005 shutdown.

• Mechanical work in the gap
• H-disk removal requires that the beryllium pipe
  be disconnected from the EC pipe at one end.
• In addition, a piping section would need to be
  removed outside the EC to allow the EC pipe to be
  moved 39 outward (the same 39 by which the EC
  is opened).
• No beam pipe cutting will be necessary.

EC
5
H Disk Refurbishment

• Detector work would be done at SiDet
• Estimate 12 weeks (including end effects), 1.5
  techs
• Part of this decision will be based on
  availability of visas for the Moscow State group
  (3 people for 2-3 months) they are not likely
  to be available next summer.
• Fixtures for H disk alignment and assembly are
  available in Lab A
• Decision can be made in late August based on
  manpower and schedule

6
Installation Clearance
Run 2a beam pipe and silicon
L0 and Run 2b beam pipe
7
Installation Clearance

• We continue to work to maximize the installation
  clearance

Run2a flange
minimum clearance
8
Installation Clearance

• We can gain enough clearance to match the Run2a
  flange by
• Removing mesh spacers between analog cables in
  area of maximum radius slight increase in
  capacitance
• Tests show that this does not affect signal/noise
• Only needs to be done in the outer (B) layer
• Removing spacers between digital jumper cables
• Using ½ oz copper and thinner adhesive for the
  digital cables
• If H disks are removed we will use the
  opportunity to survey z0 aperture

9
Installation plan

• Remove H disks
• Layer 0 slides through the North End Calorimeter
  pipe
• Is carried by a cradle (not shown) which spans
  the EC-CC gap
• Left end engages the current beryllium beam pipe
  which serves to guide L0 through the SMT

10
Installation Conceptual Design
Layer 0
Run2a pipe
cradle
11
Cabling and Connections

• We are making a mock up of the SMT support end
  region to understand space, connections and
  cabling

junction cards connected in horizontal position
then rotated 90 degrees
Digital cables in installation position
D0SMT Support
12
Online Software

• Online layer 0 occupies existing H wedge
  electronics slots so much of the existing control
  interface can be used
• Data format should be identical to SVX2
• Change database and download GUI to accommodate
  extra SVX4 bits
• Add monitoring of Weiner power supplies
• STT changes for additional inputs
• L3 tracking to accommodate additional silicon
  layer
• Much of this will be tested in the Winter using
  the SVX4 test strings installed this Fall.

13
Conclusions

• We are planning to use this Falls shutdown to
  prepare for and simplify Layer 0 installation
  next summer
• We believe that we can further reduce the
  detector radius to insure that there will be
  sufficient clearance for installation.
• We have a conceptual design for the installation
  procedure and associated fixturing.
• Hardware commissioning should be straightforward
  given shared downstream electronics and
  experience with SVX4 strings installed this Fall.

14
Cables in Dense Region