LST Upgrade LST Upgrade Readiness Review William Sands, Princeton University,

William R. Sands III,Princeton University, Installation Procedure Outline 1) Present Module Production A) Modules Completed B) Production Rate C) Projected Completion Date 2) Layer 18 Special Case A) Z Plane Installation B) Module Installation C) Utility Routing 3) Z Plane Installation A) Lower Sextant a) fixturing b) procedure B) Upper Sextant a) fixturing b) procedure C) Readout 5) Quality Control A) Overview B) Shift Time 6) Manpower A) One Shift B) Two Shifts 8) Safety 7) Conclusion 4) Module Installation A) Fixturing B) Procedure a) module insertion 1) lower sextant 2) upper sextant C) Utility Connections a) gas lines b) HV lines c) ground connections d) Phi readout

William R. Sands III,Princeton University, Present Module Production Modules are produced in 4 types an 8 cell 2 tube module (standard), an 8 cell 3 tube module, a 7 cell 2 tube module and a shorter 8 cell 2 tube for layer 18. Modules needed plus 15% for the top and bottom sextants are 138 standard modules, 14 8 cell 3 tube, 42 7 cell 2 tube and 24 layer 18 modules. Princeton University and Ohio State University share responsibility for module production. Princeton will provide 42 standard,14 3 tube, 24 layer 18 and 34 7 cell modules. OSU will provide 96 standard, and 32 7 cell modules. As of Princeton will have completed 42 standard tubes and 14 3 tube modules and move on to layer 18 modules these should take 6 days to produce. As of OSU will have produced 32 standard modules. At present Princeton is averaging 20 modules per week and OSU 16 per week. The smaller output by OSU is strictly due to space constraints.

William R. Sands III,Princeton University, Module Configuration Per Layer

William R. Sands III,Princeton University, Reference to Detector Areas

William R. Sands III,Princeton University, Layer 18 Special Case Layer 18 is a special case due to flux bars that capture the modules, because of this constraint layer 18 will be installed prior to the brass absorbers so that there is the longest available time for QC prior to it being trapped by the installation of the remaining layers. Layer 18 has a 200mm thick flux bar on the forward and backward end but only the forward flux bar can be removed which makes it necessary to rout all layer 18 utilities through the forward end. There are 4 slots in the flux bar for utility routing and although not designed for LST’s there is sufficient space for the utilities. Aside from the all the utilities being routed out the forward end, the Z plane and module installation will be done as explained in the general installation plan.

William R. Sands III,Princeton University, The cross section of the utility grooves in layer 18 is 15 mm by 100 mm as shown below.

William R. Sands III,Princeton University, Layer 18 Layer 18 resides behind the flux bar shown below in red and we are forced to run utilities thru existing grooves in the bar.

William R. Sands III,Princeton University, Layer 18 Without Flux Bars

William R. Sands III,Princeton University, Flux Bar

William R. Sands III,Princeton University, Internal conduit to place utilities for layer 18, conduits held in place with blind rivets.

William R. Sands III,Princeton University, Conduit is covered with second plate prior to flux bar installation.

William R. Sands III,Princeton University, Second plate extends up from flux bar to facilitate placement.

William R. Sands III,Princeton University, General Installation Z Planes Installation Z plane installation varies from the top sextant to the bottom sextant as does the Z plane itself. All module and Z plane insertion takes place at the forward end and in the bottom sextant there are obstructions making it impossible to install the Z planes as a single large sheet. The people at SLAC responsible for the Z plane fabrication have come up with a clever way of folding the plane on the bottom sextant to make installation possible.

William R. Sands III,Princeton University, Z Strip Configuration for Top and Bottom Sextant The Z-Strips are placed in each layer prior to the modules. The readout connectors straddle the center gap plate on the top and bottom sextants in the backward end.

William R. Sands III,Princeton University, Forward End Facing North The forward end where the Z-strips and modules are installed will have the corner plates and center gap plates removed. Full access to the layers in the forward end will allow for a much more controlled installation and is necessary to fit the Z-strips which are full width.

William R. Sands III,Princeton University, Forward End Facing East For installation of the bottom sextant we have some obstructions with the concrete pier and structural apparatus shown below. The pier is approximately 161” from the steel and points on the structure come as close as 60”. Installation of the Z planes is accomplished by folding the plane in 3 sections.

William R. Sands III,Princeton University, In the bottom sextant the Z planes can be installed by hand or using the RPC removal platform designed by Les Dittert, plan view shown below. The top sextant must use the LST adjustable removal apparatus along with another platform,shown on page 19, to allow the overhead crane to hoist the planes to the removal platform.

William R. Sands III,Princeton University, The tray is constructed from aluminum box tubing and plywood covered with mylar to reduce sliding friction.

William R. Sands III,Princeton University, Backward End Facing South From the backward end the Z-Strip readout and will exit the layers between the center gap plate and corner plates.

William R. Sands III,Princeton University, Angelo Cotta Ramusino,our electrical engineer from Ferrara, has come up with a scheme to attach the Z plane transition boards on to the center gap plate via a circuit board and copper strip in addition to some spade connectors for grounding other utilities. Z Readout

William R. Sands III,Princeton University, The copper ground bar and circuit extend the length of the gap plate picking up Z plane readouts from layer to layer.

William R. Sands III,Princeton University, General Installation Module Installation As with the Z planes the procedure for module installation is different for the top and bottom sextants. Again the RPC removal platform will be necessary for the top sextant installation. The bottom sextant in some areas can utilize a platform for holding multiple modules but due to the obstructions some have to be inserted individually. Utilities exit through the forward end and backward end with gas and phi readout exiting in the forward end and Z readout and high voltage exiting through the backward end. The utilities exit between the center gap plate and corner plate on the left and right. The modules are grouped in two halves in every layer where up to 5 modules will be feed from one gas input and output. Each module has one high voltage cable and two phi readout cables with the exception of the 3 tube modules which have 3 phi readout cables. Utilities are routed to the outer perimeter of the detector through “incremental conduits”. Conduits are sectioned to only take up space in already installed layers.

William R. Sands III,Princeton University, Installation Platform The installation platform can hold up to half the modules per layer. In the top sextant where there are no obstructions it can be loaded to capacity.

William R. Sands III,Princeton University, Example of incremental conduit installed on detector after modules are installed in individual layers have been installed. Weld studs are inserted into steel plates to hold conduit and cross pieces inside channels are for strain relief using cable ties. Yellow in layer slots represent brass absorber layers.

William R. Sands III,Princeton University, Pictured below is a phi transition board on a 3 tube module. The phi readouts exit through the forward end. The phi cable is connected to the transition board and routed to the conduit where it leaves the sextant.

William R. Sands III,Princeton University, Below is a 2 tube module with HV boxes and connecting strain relief. HV wires are stranded out of the bulk Kerpen cable and soldered to pc boards inside the HV boxes. The bulk cable is then attached to the stain relief with cable ties. strain relief HV box

William R. Sands III,Princeton University, High Voltage Cable Connector The high voltage connector was introduced so that during installation the entire HV cable didn’t have to be handled. Dave Warner, at Colorado State, was brought on to work on the HV connector design. The main criteria for the design is that they be as small in cross section as possible and sustain the required voltages with a reasonable margin of safety. Dave presented a design of two connectors one 11 pin and one 16 pin. The 11 pin connector is used for the 2 tube modules and the 16 pin connector is used for the 3 tube modules. The connectors reside outside the detector in an area where the HV cables leave the conduit. This area offers the required space needed, Peter Kim acknowledged that the space was available.

William R. Sands III,Princeton University, High voltage lines and boxes are connected to the modules at the forward end and the HV connector end of the cable is tethered and pulled through the layer gap. The HV lines must be guided as the modules are being pushed through the gap, once the modules are in place the HV line can be routed into the conduit.

William R. Sands III,Princeton University, Pin Connector Cross Section Female Connector Male Connecter

William R. Sands III,Princeton University, Grounding Scheme Horizontal spade connector Ground wires are run from individual utilities to vertical spade connectors riveted to a Cu clad board that connects all grounds on the board. Horizontal connecters can be accessed in the gap and will daisy chain modules together, up to 5 modules, and also connect to ground on the center gap plate. Vertical spade connector

William R. Sands III,Princeton University, Quality Control Quality control begins with handling of modules and they will be handled as carefully and as little as reasonable. As soon as possible after module installation they will be tested for High Voltage and gas integrity. An overnight test on readouts will be done with cosmics. If any problems are detected, replacement or if possible a fix will be the first priority on the next installation shift. Testing will continue as long as possible without interfering with installation.

William R. Sands III,Princeton University, Manpower Ohio State, Princeton, Colorado State and the Italian collaborators are presently in the queue for supplying personnel for installation along with SLAC crews for rigging and staging. There will be several people versed in all aspects of the installation that will act as shift managers as well as being part of the installation crew in all there should be upward of 20 people available. It is still to be determined if 2 installation shifts will be possible. Two shifts are only feasible if a layer on the top and subsequently a layer on the bottom can be done. It is unadvisable to do 2 consecutive layers prior to QC so the area will not be obstructed by the next layer’s cabling if there is a problem.

William R. Sands III,Princeton University, Daily Plan Each day in two shifts the plan is to install one layer or more if possible. A third quality control shift then comes on tests the modules each day. If a problem is found the first task the next day is to replace the faulty module and then move on to the next installations. It has been found that tube can sometimes be repaired, if this is the case the module will be used as a spare or installed in another sextant at a later date.

William R. Sands III,Princeton University, Safety Safety is a major concern for all involved. There are many aspects to this issue including overhead, electrical and fall protection. It is important that there are enough people for every operation and not too many to encumber the movements or egress of others. Along with SLAC safety personnel the shift managers and individual workers will pay considerable attention to safety issues.

William R. Sands III,Princeton University, Conclusion The module and Z plane installation will proceed in mid August. This is a huge undertaking and has been thoroughly thought out by many experienced people. Jim Krebs and his group are constructing a mock layer with all obstructions replicating a layer in the bottom sextant where the difficulty is highest. During the week of June 7 th an installation will be done in this mockup and plans will be tweaked and changes made if necessary.