BEAM - Beamline
Raja:
We had a MIPP beam line meeting today and I raised the question of beam fluxes permitted in MC7. The answer from Chuck Brown can be summarized as follows.
During beam tuning, we will need to restrict the flux into MC7 to be < 106 particles per spill for radiation safety reasons. There is no way they can bring 1011 into the enclosure with its existing state of shielding. So the old scheme of tunign the beam by bringing 1011 into MC7 is no longer valid.
So even during beam tuning, the calorimeter would be OK in its installed position.
Secondary beam will be tuned using MIPP beam chambers and not using SWICS for the same reason. So it is in MIPP's interest to get the beamline instrumentation and DAQ for the beam chambers working early on.
At [last Thursday's] meeting it was decided to have the MIPP primary copper target be a rectangular rod of 20 cm length and cross section 0.5 cm square. The primary beam spot is expected to be collimated and to be ~ rectangular of 0.4cm square on target. Mikhail Kostin made a first pass at shielding. Chuck pointed out that the shielding was too good by ~ a factor 100, so Kostin is going to try and reduce the iron in the shielding, which makes it easier to install.
Raja reserving space for beam scintillators at either end of the BCKOVs.
UBL - Upstream Beamline Detectors
BCKOV
Terry Tope:
Attached is a req for a pressure transducer [Transmitter, Barton AII Absolute, FKAG-03V4-ADCYYAA, 0-14.7 PSIA calibration range, 4-20 mA output] for each beam ckov. I could not find anything on site that I am comfortable using to calculate the density in the beam ckov. They are +/- 0.1% over the calibrated range of 14.7 psia. We have several pressure instruments from this company on site and they are easy to calibrate and the company supports us quite well. I think we should go ahead and try and purchase these. For my test I have a cheaper one, but I would not try and do physics with it.
I made a plot of the instrumentation error for the bckovs (attached .pdf). The blue line is the transducer I made the req for. The red line is an additional transducer that could be purchased for the lowest absolute pressures to improve density calculation accuracy.
The points I want to make are:
- RTD error is insignifcant compared to pressure transducer error.
- The pressure transducer error for the 0-14.7 psia instrument I want to buy could lead to a density error of 1% at 1.742 psia.
- Adding a second 0-2.321 pressure transducer would delay the possible 1% density calculation error until 0.545 psia.
So the question is then, is the error of the blue curve acceptable? If its not, then the only solution I see is to buy a 2nd transducer. Food for thought.
Photos of the beam ckov test vessel [are posted on BCKOV page]. Its pretty much done and ready to go. It has 6 RTD temperature elements and fast/slow gas fill and fast/slow vacuum capability. It should gives us an idea if this idea is what we really want. So the sooner we get the APACS modules ordered the better. I'm still working on the programming for the ckov and the gas mixing. This week I need to go over where I want to place the various gas racks with Leon.
Pipe length getting longer with new beam line design; Opal/Smith to update MC7 floor plan drawing.
![[Eric Erdos'] sketch](http://ppd.fnal.gov/experiments/e907/Targets/target2test.gif){kind=link}