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<div>Thanks! We're in the ballpark then...! </div><div><br></div><div>Steve, or anyone, is there a field diagnostic in place to get the value?</div><div><br></div><div>Thanks, </div><div>DD </div><div><br></div><div><br></div><div><br></div><div id="composer_signature"><div style="font-size:85%;color:#575757">Sent from my Verizon Wireless 4G LTE smartphone</div></div><br><br>-------- Original message --------<br>From: Ross Corliss <rcorliss@mit.edu> <br>Date: 08/04/2016 2:47 PM (GMT-05:00) <br>To: douglas@jlab.org <br>Cc: felman@jlab.org, Christopher Tennant <tennant@jlab.org>, darklight <darklight@mit.edu>, dlsupport@jlab.org <br>Subject: Re: [ 1433] A voice, crying in the wilderness <br><br></div><br><div>
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<div class="PlainText">I dug up an old excitation curve from the magnet's previous experiment (page 24 of the attached), but it's definitely not precise enough for this task (though it verifies that ~2kA = ~5kG).<br>
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-Ross<br>
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> On Aug 4, 2016, at 2:42 PM, David Douglas <douglas@jlab.org> wrote:<br>
> <br>
> okay, so, looking back at the attached, I see 500 A gives 1.2 kG? So if it's completely linear we'd need 2083 A for 5 kg?<br>
> <br>
> The concern here is that the optics solution depends very sensitively on the solenoid internal field - 1% deviation is likely significant, 10% error in field would be a serious issue. We can recalculate, but to validate the setup we'll need to run the solenoid
at the same field as during the physics run. Do we have a way to measure the field in place? Do we know the excitation curve?<br>
> <br>
> Again, guidance is welcome. Thanks<br>
> <br>
> D<br>
> <br>
> <br>
> <br>
> On 8/4/2016 2:33 PM, David Douglas wrote:<br>
>> Just read log entry<br>
>> <br>
>> <a href="https://logbooks.jlab.org/entry/3416301">https://logbooks.jlab.org/entry/3416301</a><br>
>> <br>
>> regarding solenoid. It recommends 2000A limit for this run.<br>
>> <br>
>> If this does not produce 5 kG field in the solenoid (which I thought took order 5000A), it will blow away the optics solution: the beam transport will be completely disrupted, in that both the betatron match and the coupling compensation will be incorrect.<br>
>> <br>
>> Please advise.<br>
>> <br>
>> DD<br>
>> <br>
>> <br>
> <br>
> <DL_Sol_fieldmap1-1.pdf>_______________________________________________<br>
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