where, BPM_y[cm]
=([bpmay]+327.15*([bpmby]-[bpmay])/(327.15-231.46))
and the bpm values were taken from the raw entries in the epics scaler
files. The bpm values were divided by 10.0 to convert from mm to
cm. Plots used to determine
the vertical BPM's
The beam vertical position was
determined using hsxptar using HMS_vert(up)
[cm] = - (mean hsxptar) *1000. / -1.73 /10.0,
where (mean hsxptar) is the mean of the peak from the central sieve
hole. The factor of 1000. converts rad to mrad. The factor
of -1.73 is Henk's
conversion factor. The factor of 10.0 is to convert from mm
to cm.
The cuts used were:
hcer_npe>2.
abs(hsyptar)<0.03
abs(hsxptar)<0.04
abs(hsdelta)<5.0
The vertical position determined using the HMS for run 50130 was
checked against Dave's
value. His result was y_beam = -0.12mm. My result
was 0.096 +- 0.032 mm, where the error is 1 std deviation of the
mean. When Dave projected the BPM to the target for this run, he
obtained -0.43mm, I obtained -0.48mm.
A possible reason for the two points in the bottom right corner are
that they are from the December '04 running period. The remaining
data points are from Sept '04.
The
two running periods were separated in the plots below and the slope was
constrained to 1.0
