Comments for Review of NuMI Primary Beam
                   Monitoring & Instrumentation

                           Aug  14, 2001

                   from  Tom Kobilarcik



1. Overall Remarks

Instrumentation requirements need to be specified more precisely.  For example,
the specification for the BPM position measurement error is quoted at 0.2 mm rms
within +/- 20 mm, even though this accuracy is needed only for the central part
of the BPM.

I had the impression that the overall cost of new instrumentation has been
accounted for correctly in the NuMI budget, but only a portion of the cost was
shown in the presentation.  This may seem misleading.


2. Itemized suggestions, questions and concerns

(1)  I did not see any data showing what is achievable using existing systems
(perhaps this was shown at a previous meeting).  How long a stretch is it from
what we do now to what NuMI needs?

(2)  Does a plan exist for testing a prototype in an operating beamline/transfer
line?


(3)  How robust is the autotune algorithm in regard to non-uniform errors or
non-linear response in the same device?  For a given BPM, how far can the beam
move before the rms error is the same size as the correction?  How far can the
beam move before a convergent solution is no longer possible due to errors, that
is, what is the "tuning window" defined by the instrumentation?  How does this
window compare the the expected centroid rms due to power supply ripple,
extraction errors, and such?