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Please keep a running tab of all things to do in the foreseeable future.  Lets keep things moving and make the most of our time at Fermilab.  Anyone can add tasks here.  Once a task is complete please remove it from the list here and my an entry in the ECL logbook about that task being complete.  If you purchased and received the item list in the ECL where it will be stored.

 

 

Do ImmediatelyAdditional Information

Fridge sensors

1KOhm Ruthenium Oxide
Determine and measure true path for all cables coming from target cave and order all cable needed

Front Penetration → Racks on Cryo platform → Counting House

Side Penetration → Racks on Cryo platform → Counting House
Replace Black BUNA-N O-rings

Measure existing O-rings and find PTFE (Teflon) equivalents

  • Run/bypass valves
  • Shell to magnet
  • Shell to turret
  • Turret to fridge
  • Electrical feedthroughs
  • Bottom can
  • Red pop-off valve
After replacing seals setup safety walk through withSetup Operational Readiness Clearance (through Rick)
Buy a flaring tool for copper tubing 
Assemble and test microwave system

Needs to be shipped from UVa - 7/17/19

Borrow gore cable from UVa

Need waveguide too

Get Liverpool NMR Q-meter (and ancillary equipment) from LANL 
Setup temp full microwave system for testing here 
Setup sensors on stickCheck with lakeshore
Stink test in the target loading areawith "special" spray
Setup and test manometer 
Setup external magnet sensors with data going into slow controls data stream 
Shim Microwave actuator bushings for hard stop and top target. Microwave table and magnet should be in place and use the information from initial survey to measure 
Setup LANL NMR system for testing in counting house target area 
Setup UVA NMR system for testing in counting house target area 
Things to do when not working on the immediate thingsAdditional Information
  
Setup Target Rack

Stepper motor drives and power supplies

ADC for position readbacks

Microwave EIP

Lakeshore 218 x2

Level Probe Readout

Turbo readout and Controller

IV gauge readout

Teledyne Hastings readout

4He & 3He manometers

Possibly Microwave Power Supply

Target Insert Lakeshore

Fridge Lakeshore

External Magnet Lakeshore

 

Get hoses for microwave (EIO)Either hard plastic or rubber
Target Controls ComputerJosh will find it
All cabling from target to racks and counting houseneed lengths and to order cables
setup target operator station 
setup target loading station 
Finalize NMRtesting still needed
Target handler and alarm system 
Setup NMR VI 
Annealing controls 
Setup and test Main Gate Valve 
Test Air-core cable with EIP/microwave 
Setup Insert and leak check and electronics check, sensors, coils, SMA 
Setup Nuc and oscilloscope and PDP 
Setup Roots stack controller and power 
Get some plastic tubs and foam dewars 

 

For SpinQuest it will be difficult to get the positioning of the target perfectly aligned with the beam. This is because all fiducials that we can get while the system is warm and open will change once we are running with liquid helium. We have X, Y positioning measured from averaged vertex reconstruction but this takes at least 1 month of data to produce, and this will only give the mean with a very large variance. This means we need to get the information we need from the survey and the final set of surveys will need to contain some cold target information. The precision in the target cell to beamline positioning needs to be good to mitigate large absolute errors while running. This is estimated to be on the sub-millimeter level (based on simulations being confirmed). There are several factors that can lead to false asymmetries relating to this precision. There can be a bias produced in the detector if there the beam is off center. There can be less polarized scattering if the beam is not aligned and missing part of the target (beam profile dependent, also being checked). There can be greater scattering off the aluminum ladder on one side as compared to the other. Most of these manifest from X being off but if Y is off over 1 mm then the same issues start to manifest with the ladder as well but this may not result in false asymmetry and only result in additional heat load to the coils. During our discussions with the survey crew it was suggested to install transparent windows so we could do an optical survey on the magnet and target cells while cold. This would be great to do but I do not think this is possible at FNAL. I don't believe we would ever pass a safety review to do that. The next best option is to do surveys using liquid nitrogen. We could calculate the level of contraction for both LN2 and LHe. We can then measure the contraction during an open system survey with LN2 in the magnet and in a nose with a window on it. The set of survey would go like this:

1.) The dock survey should be with a fully open system (no nose, no nitrogen shield, no beam windows). We will survey the magnet aperture opening planes  and the target ladder. The insert ladder should only be studied in X for this setup (put top cup in the near beam-line position using piston configuration). We should move the magnet to some level place on the dock and set it up on to a tooling table. We should try to do as much of the preliminary setup ourselves (and with techs as needed) so the survey crew can come in and setup quickly. To survey the aperture opening planes we should get the location of each of aperture corners and three points between each of the corners. This is a total of 16 points per plane (32 points all together). The distance from these points to the a set of references on the top flange will need to be measured. The locations of these reference points on the top flange will need to be chosen by us. We will also setup the top target cell with front and back cross-hairs and measure the x, y, z of the cross-hairs and the inner cell wall with respect to the top flange. Several positions at 3mm increments should be chosen on the target cell. We should get the location of each of the magnet opening corners and at least two point in between in each of those points along the aperture openings. The aperture outline and ladder-X should be projected as outside fiducials and referenced to the top flange.

Work needed to optimize the survey:

1.) Make sure piston and target insert are ready

2.) Setup cross-hairs on target cell (may need to discuss with survey folks)

3.) Chose locations on target cell and top flange for measurements and reference

4.) Finish target insert and refrigerator work

Its also possible to make the bottom can so we return to the same measured locations when can is removed and put back into the cave (using high percission dowel pins). I’m not sure this is necessary because we will not use the bottom part of the can to reference against anything. Slight rotations from starting should be addressed by Mitchell's alignment setup.

 

 

2.) Survey in cave using LN2 in nose and magnet. This would be a partly open survey with a special nose put on with transparent windows on either side for optical survey. The nitrogen shield and beam widows on the vacuum are left off for this. This survey in the cave will be of the magnet aperture, the target insert along X, Y, Z, and the outside fiducials (can and top flange and reference locations in the cave). Crosshairs will be use in the front and back of the target cell to help determine degree of twisting in the cell. Cross hairs in the can windows can also be use to set the rotational alignment of the can. The target insert carbon fiber is not expected to contract very much but the aluminum ladder can. The primary goal of this survey is to compare to calculations of contraction and measure positioning of target cell with respects to magnet aperture and also with respect to the beamline. There should be a hard stop setup on the actuator that positions the top target exactly in the beam line (to test repeatability of the string potentiometer and gears). We also need to take the stick out and few times and test the scale of  deviation in reproducibility in target cell shifts and bends. This will take two surveys to do since we will need to machine the piece for this hard stop after this first cold survey measurement. In order to do this the actuator and motor should be installed so we can move up and down with reasonable repeatability. This repeatability can also be tested during this survey. The drawings indicate a change of 4.5 mm up when cold.

3.) Put in hard stops and re-survey. This will be adding a shim to the hard stop that already exists. Here we can have the goal of .25 mm target centering in X,Y and measure a set of cells using cross hairs in Z.

4.) An X-ray survey while cold would be the next step if possible. We may not needed it if we achieve good results from the first 3. It may also be possible to use phosphine graph paper to check beam position on a special target insert without depending on the magnet or nose having LHe in them.  Or use something that discolors or burns in the beam so we can make an insert that will be use over the experiment to check position.

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