<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>I can supply the current. I will send it later.<br><br>Sent from my iPhone</div><div><br>On Jan 17, 2014, at 12:23 PM, Daniel Sober <<a href="mailto:sober@cua.edu">sober@cua.edu</a>> wrote:<br><br></div><blockquote type="cite"><div>
The attached table and figure (and the Excel spreadsheet it comes
from) shows a comparison between the field/current ratio (at pole
center) from the data and from Tosca. Since your spreadsheet gives
the current only in "PPM", I have adjusted the ratios to make them
agree at 1.5 T. The consistency at 0.75 T, 1.5 T and 1.7 T looks
quite good. (I have connected the measured points by straight line
segments to make it easier to see where they are.) <br>
Measured ratio (P1) Tosca ratio<br>
0.75 T 2.0867 2.085 (average
of 0.6 and 0.9 T)<br>
1.50 T 2.0307 2.0311<br>
1.70 T 1.8461 1.8582<br>
This is important in case we have to interpolate between the maps to
run at an excitation other than 1.5 T.<br>
<br>
The measurements at 0.1 T and 0.0536 T are way off the curve. Since
the Hall probes and the NMR agree, the only sensible explanation is
an offset in the power supply reading. Does anyone have a
calibration of the current reading? As long as we have the NMR
probe, I guess the current is not important.<br>
<br>
Dan<br>
<blockquote cite="mid:2132315862.2236727.1389972652886.JavaMail.root@jlab.org" type="cite">
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<div class="moz-signature"> -- <br>
<font color="#ff0000"><i>Daniel Sober<br>
Professor<br>
Physics Department<br>
The Catholic University of America<br>
Washington, DC 20064<br>
Phone: (202) 319-5856, -5315<br>
E-mail: <a href="mailto:sober@cua.edu">sober@cua.edu</a></i></font><br>
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<br>
<div class="moz-signature">-- <br>
<font color="#ff0000"><i>Daniel Sober<br>
Professor<br>
Physics Department<br>
The Catholic University of America<br>
Washington, DC 20064<br>
Phone: (202) 319-5856, -5315<br>
E-mail: <a href="mailto:sober@cua.edu">sober@cua.edu</a></i></font><br>
</div>
</div></blockquote><blockquote type="cite"><div><B_current_ratio_vs_Tosca.pdf></div></blockquote><blockquote type="cite"><div><Hall_Probe_calib_config2.xls></div></blockquote></body></html>