Minutes/Notes
                E614 COLLABORATION MEETING
		  February 27-28, 1999
 Morning of Feb. 27 (Saturday) was devoted to presentations of the
design status of the following list of items.

 Status of detector assembly design;       Robert H.

 Status of chamber support design;         Peter K.

 Status of magnet shield design;           John M.

 Status of clean room preparations;        Yuri D.

 Status of front end design;               Grant S.

 Status of gas system design;              Robert O.

 The afternoon was devoted to a Round table discussion of the designs
as presented. The goal was to reach agreements to proceed with
construction or design work.

A/ Configuration of the PPP module as a regular xy pair type A was
ACCEPTED. The following suggestions and modifications will be taken
into consideration. The person listed opposite each item will report
at the next collaboration meeting.

 1) Second cathode connection to ground;         Robert H.
      - will it fit?
      - will it help?

 2) HV resistor 
      - move it to larger radius or to VTX support board; 
        This will be done. Its possible since space is no longer
        at the premium it was in earlier designs.
          size?                                  Robert H.

 3) VTX; they are on short cables. And they are soldered "somehow"
         to the CDF chamber. An exploratory visit will be made to
         determine best way to "extract" preamps.
      - can the existing cables be used without desoldering?
          decide to wait until we find out about the mounting
          and the nature of the cables.
                                                 Grant S.

          We will continue with design without these cables.

 4) Filter (storage) capacitor
     - AC ground to ground.
          What value?                            Robert H.


B/ The design of chamber assembly was ACCEPTED as presented.  The
following suggestions and modifications will be taken into
consideration. The person listed opposite each item will report at the
next collaboration meeting.

 1) Considerable discussion was held on the scheme to move the assembled
detector from vertical to horizontal and back!
 Presently the scheme as follows is TENTATIVELY ACCEPTED.
    - stack chamber modules,
    - compress Cital and tighten nuts            Jan S.
    - bring up cradle
    - put bolts (spring loaded) in place
    - lock to cradle (bands?)                    Robert H.
    - tilt to horizontal
 The question of the safety of this procedure was discussed and it was
suggested that a Stress analysis at 45 degrees be made.
                                                 Jan S.

 In addition it was suggested that the procedure be tested with the
real cradle and a dummy chamber.

 2) Heat removal via a flow of dry nitrogen was discussed and
APPROVED.
    Design work on how this will be done will wait until the chamber
services are finalized. Do we want to establish and hold constant
temperature?  It would be helpful to form a "tent" around the magnet.
A table of temperature requirements and expected temperature variations
in the M13 area is required for a rational discussion. Perhaps CHAOS
has considered this problem?
                                                 Dave G.

 3) The positioning of services (cables and hoses) may make chamber
removal problematic.
    This will be taken into account in future design work.
                                                 Robert H.

 4) Optimizing the use of the available Cital was discussed and it was
decided that the proposed AB module was not an optimum configuration
for the physics requirements.
 The present limits on what are defined as ``usable'' Cital will be
reevaluated. Is it possible to get the poor ones reground?
     A search for a source of new Cital will be made.
                                                 Vladimir S./Dave G.

C/ The gas handling system design was ACCEPTED as presented.
    Gas recycling for the CF4/Isobutane was APPROVED. A design to make
possible DME recycling will be sought.
                                                 Robert O.


D/ The concept of mounting the Postamp/Discriminator in racks attached
to the magnet yoke was ACCEPTED. The concept of designing the P/D
board to carry 32 channels and to be mounted in a 6U module/crate
system was APPROVED. The use of alpha cables "of minimum length" was
TENTATIVELY APPROVED. A detailed design of the rack usage is needed.
                                                 Grant S.

The actual Postamp/Discriminator design work has been delayed because
Vladimir T. has had an accident.
   Vladimir S. presented the status report on this design. The circuit
diagram is available on the home page under E614 Collaboration
Meetings.  Several discussions were held regarding this conceptual
design;
 1) The MC10116 as used in the design will present an amplitude
dependent input impedance. This is not acceptable! Clamping amplifiers
were suggested as a solution for this problem. They could be expensive.
                                                 John S.

 2) The crosstalk within the AD96687 discriminator is suspected to be
small but a number is required. Do a test?
                                                 Grant S.

 3) Option employing capacitor C8 was APPROVED. (time over threshold +
a constant is the preferred option.) A pad that will allow the
installation of the appropriate capacitor if it is found to be
required will be included in the P/D board design.
 4) A lemo connector will be mounted on the front or back panel of the
6U module for providing external control of the threshold. Control will
allow the threshold to be set for each chamber plane independently.

 A special meeting will be called to discuss the P/D design in detail
on Tuesday-Wednesday March 9-10. Manpower requirements for the design
and manufacture of these boards will also be discussed.
                                                 Dave G./Nate R.
 The design of the postamp for the ADC channels has not begun. This
card should also carry the ADC/TDC interface chip (MQT300).

E/ Conceptual designs of cradle/sled/track were APPROVED. Continued
work on this scheme was recommended. See the discussion of the 
mounting scheme and the method for vertical to horizontal movement
of the assembly above.
                                                 Jan S.

    The alignment checking/monitoring scheme using lasers and CCD
cameras was APPROVED. See Technote 27 on the E614 home page. Further
development will follow.
                                                 Peter K.

F/ Conceptual design for magnet yoke with the smaller size and rear
opening door was APPROVED. Monte Carlo studies of effect of new field
will follow.
                                                 John M./Dennis W.

G/ Conceptual design of layout in M13 was APPROVED.
 1) Racks for Fastbus should be kept at a distance from P/D's
that are to mounted on rear door of yoke.
                                                 Grant S.

NOTE: TRIUMF requires an engineering/safety review of these systems.
 The collaboration agreed to hold the review of the design of the
Postamp/Discriminators in early April (an exact date will be fixed
shortly).
The collaboration agreed to hold the review for the cradle/sled/track
and for the magnet yoke in early June (an exact date will be fixed
shortly).

Sunday February 28/1999.
H/ Robert H. presented the chamber construction and quality control
procedure. The collaboration is to peruse it and to comment on it
before or at the next collaboration meeting.
                                                 Robert H.

I/ A numbering scheme for the wires and planes must be devised before
the
assembly work begins. The labeling of the planes as uv rather than xy
was
discussed without a conclusion being reached. The chamber group will
discuss this issue at their next local meeting.
                                                 Dave G.

J/ Jaap D. presented a study he has made of the interface between M13
and the solenoid, i.e. how many muons can we get across the fringe
field. His report is posted on the home page as Technote 28.

K/ Dave G. discussed the schedule for the assembly work that is to take
place over the next two years. The goal of having the PPP ready in
early July looks reasonable. There will be a crunch in getting the
postamp/discriminator boards designed and built on this time scale.

 The assembly of the magnet yoke and the mapping of the field will not
begin until Chaos moves out of M13, now estimated to be at the end of
the summer beam schedule in 2000. This means that there will be a
large portion of the detector available before the magnet is
available. These pieces of the detector could be assembled and exposed
to beam. The collaboration agreed with this scheme and decided that
this test should include a pair of xy modules and a dense stack. The
aim will to put this subsystem in the beam(M11) in April 2000.

 Assuming Chaos moves out of M13 in Aug. 2000 the E614 magnet will be
available in M13 for initial studies in early 2001. A large portion of
the detector assembly (if not it all) will be available at that
time. Systematics and physics experimentation can begin shortly
thereafter.

 An updated schedule showing the subsystem test will be posted shortly.
                                                 Dave G.

 The production schedule will put considerable pressure on the E614
manpower. The following list shows procedures where temporary workers
will be required. The term "Experts" is shown in quotes because some of
the
temporary workers may be train-able.

Cathode foils glued in G10 rings;
    "Experts" required for manufacture
  Temps do QC 
         - tension adequate
         - leak tests
Glue lamel to glass plates;
    "Experts" required for manufacture
Glue Cital rings in glass plates;
    "Experts" required for manufacture
Glue cathode foils in glass plates;
    "Experts" required for manufacture
  Temps do QC 
         - leak tests
String wires on prepared planes;
     "Experts" required for Stringing wires
   Temps do QC
         - wire tension
         - wire positions (survey & record)
         - HV testing
Assemble planes to form xy modules;
     "Experts" required for assembly
   Temps do QC

Technical Help?

L/ Target Region;
 A round table discussion of the target region was held. There were
basically three proposed schemes. Two involved creating an additional
volume in the region of the target. The charge would be drifted out of
this region through the introduction of a grid plane. This would leave
a volume into which a slide or a wheel could be introduced to allow
for changing of the target. These schemes would introduce extra
material between the upstream and downstream sections of the
detector. This extra material would make detector calibration
difficult. A number of questions about these schemes were asked;
1) How thick and what would this material have to be?
2) How many grid wires are required? A Garfield study should be made.
3) How many muons will stop in the grid wires?
4) How will grid wire stops be identified.

 The third scheme also involved sliding in a new target cell
consisting of the target and PC's +/-1. However in this case no extra
materials would be introduced since the "carrying frame" would be
removed once the new target cell was "bolted" in place. Since the
cathode foils common to PC's +/-1 and PC's +/-2 would have to be
replaced, each having an independent cathode foil, there would be a
dead layer introduced between the cathode foils of PC's +/- 1 and
those of PC's +/-2. A number of questions about this scheme were
asked;
1) What would be the effect of these dead regions?
2) What would be the effect of the extra cathode foils?

 This scheme and the original scheme have the problem of keeping the
target foil flat and accurately positioned. (The slide scheme above
also has this problem if the material surrounding the target is
minimized.) No solution to this problem is presently known!
1) Can pure Al be hardened?
2) Can a scheme of strings and rings reduce the scale of the problem?

M/ The May Collaboration Meeting was discussed. Reports/updates on the
detector assembly/design are needed at that meeting. It was therefore
decided to move the meeting by a day and extend it by a day.  The Next
Collaboration meeting will therefore take place May 26-28, the first
day and a half being devoted to the topics listed below and to the
reports from the people whose names appear in the above minutes.  The
afternoon of the 27th and the 28th will be devoted to software
discussions.  The meeting is now taking place in parallel with the
TRIUMF EEC.

i) Progress reports (from above minutes).

ii) Program of tests for July - August

and
   - DAQ plans for July & August

   - Analysis plans for July - August

iii) Beyond July - August test.

   - Beamline controls

   - Target region design

   - Two xy pair + dense stack test.

   - Monte Carlo priorities list

   - Construction schedule

N/ A conference call will be attempted at 10:45 on Wed. March 17 to
bring offsite collaborators into the local group meeting.

-- 
*****************************************************
David R. Gill (drgill@triumf.ca)   (604) 221-3219
TRIUMF                              Fax  222-1074
Vancouver, BC
V6T 2A3

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