<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Can we PLEASE, PLEASE narrow up the C slit while delivering 30 uA to the Hall C dump as in the outline I submitted for review to some portion of our membersihp?
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Outline: <br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Deliver 30 uA to C</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Turn A off to allow increased current draw from C laser<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
read BLMs</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Narrow slit to restrict to 15 uA</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Raise laser intensity to restore 30 uA</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
read BLMs</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
narrow slit to restrict once more to 15 uA</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
as available, raise laser intensity to restore 30 uA to C</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
read BLMs</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
If laser maxed out before 30 uA available, open slit to give 30 uA at max laser</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
reduce current lock setting to 25 uA</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
slowly open slit to return to open condition while current lock reduces laser intensity</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
compare BLMs along the way</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
This is something which should take not very many minutes and for which I asked feedback quite a few days ago. Feedback now? We do not have to wait for Hall C to come back to get this information. It is not exactly the "A laser through C slit" test, but
it is a "restrict temporal gate at C chopper" test which strongly overlaps. As time is available, one might also reduce the pre-buncher to gain additional information, but this is not a first-line part of the proposed test. This will give us useful information
as outlined above.<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Michael Tiefenback<br>
</div>
<div>
<div id="appendonsend"></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> BTeam <bteam-bounces@jlab.org> on behalf of Matthew Bickley <bickley@jlab.org><br>
<b>Sent:</b> Tuesday, March 10, 2020 09:27<br>
<b>To:</b> bteam@jlab.org <bteam@jlab.org><br>
<b>Subject:</b> Re: [BTeam] no bteam today.</font>
<div> </div>
</div>
<div dir="ltr">
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
I'll add some context that Yves shared with me before he headed home after being here over night. Following our earlier studies we have pretty high confidence that the activation we are seeing in the arcs is the result of the width of the beam pulses coming
from the C laser. The last test we want to execute, which was scheduled but we ran out of time for, is to send the C laser through the A slit. That will need to be done to confirm our understanding of the source of the activation. Unfortunately, because the
current experiment in Hall C is nearly complete we won't have time to perform the study before this run is over. We should expect to perform it late next week at the earliest, once the next run starts in Hall C following their experimental equipment change.
When we hold our BTeam meeting next week we'll refine our planning for this test as well as discuss additional tests that could be done to understand machine performance.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
Matt</div>
<div>
<div id="x_appendonsend"></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="x_divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> BTeam <bteam-bounces@jlab.org> on behalf of Yves Roblin <roblin@jlab.org><br>
<b>Sent:</b> Tuesday, March 10, 2020 8:38 AM<br>
<b>To:</b> bteam@jlab.org <bteam@jlab.org><br>
<b>Subject:</b> [BTeam] no bteam today.</font>
<div> </div>
</div>
<div dir="ltr">
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
We will have one the week after that to present the result of previous beam studies and plan for next round of studies.
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
</div>
</div>
</div>
</div>
</body>
</html>