Hello,
at the last meeting (the minutes are still in my crashed HD..) we agree
on using a uniform scaling factor to be applied to projection of future
data.
We also agreed that one should assume the current target thickness and
polarization "as is". This eliminates 40,60 cm, M=2, M=4,.. discussions.
As a benchmark I then take last week's running, when we integrated 23.6 kC
over 7 days, and 16 shifts (I take out 5 shifts lost due to power failure
recovery). That makes it 1.5 kC/shift.
So <on average> we should be able to integrate 25.5 kC/week. Counting for
another 13 weeks, that should add up to be about 330 kC. This corresponds
to 1000 continuous hrs with a flat 91.2 mA current. So please scale your
statistics (at the current yield, polarization) to 300 kC.
The goal is to have that much by october 17 (with no other contingency).
I guessed that during a typical production week we "lose" 4 shifts of ABS
data due to a) snake-fill b) empty-tgt c) unpol_running, which corresponds
to an 80% beam-on-pol-target efficiency. Clearly some weeks it may be
only 3 shifts, some others we may overall loose more time. You can argue
that the above estimate is a bit conservative but it is a good start.
Note that last week we had injection current was 140-150 mA, lifetime was
around 25 mins, with dead time of 20 % at 130 mA, 10 % at 90 mA, adding
another 15 % inefficiency. We mostly re-injected at 90 mA, which was
optimal.
-- ________________________________________________________________________________ Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124 research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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