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-------- Original Message --------
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<th nowrap="nowrap" valign="BASELINE" align="RIGHT">Subject:
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<td>Re: BCM accuracy</td>
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<th nowrap="nowrap" valign="BASELINE" align="RIGHT">Date: </th>
<td>Mon, 6 May 2013 18:30:51 +0800</td>
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<th nowrap="nowrap" valign="BASELINE" align="RIGHT">From: </th>
<td>Pengjia <a class="moz-txt-link-rfc2396E" href="mailto:pzhu@jlab.org"><pzhu@jlab.org></a></td>
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<th nowrap="nowrap" valign="BASELINE" align="RIGHT">To: </th>
<td>Jian-ping Chen <a class="moz-txt-link-rfc2396E" href="mailto:jpchen@jlab.org"><jpchen@jlab.org></a>, Alexandre
Camsonne <a class="moz-txt-link-rfc2396E" href="mailto:camsonne@jlab.org"><camsonne@jlab.org></a></td>
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<div dir="ltr">Since T3 rate also depends on target type and
momentum setting, I need to find a period that have stable
momentum setting and same target for more than 20hours(i don't
know if it has or not,maybe I can try to look at the gep data,
though it is at low current as 5~10nA), or I need to find a new
way to check the stability other than T3.<br>
<br>
</div>
<div class="gmail_extra"><br clear="all">
<div>
<div>Pengjia</div>
</div>
<br>
<br>
<div class="gmail_quote">On Mon, May 6, 2013 at 5:27 PM, Pengjia
<<a moz-do-not-send="true"
href="mailto:zhupengjia@gmail.com">zhupengjia@gmail.com</a>>
wrote:<br>
<blockquote class="gmail_quote">
<div bgcolor="#FFFFFF" text="#000000">
<div>
<div class="im">
<div>Hi JP,<br>
Sorry for late, I don't know the deadline is tonight
before.<br>
I checked several production runs by using T3 count
and bcm count saved in helicity ringbuffer(since
there is more events saved in ringbuffer raw data(1
event recorded per 0.001s) than in normal sis3800
scaler(1 event recorded per 2s), also I checked from
normal sis3800 scaler and got same result), the main
idea is:<br>
1.calculate the charge(after calibration) rise,T3
count rise per 1 second(bcm count rise in 1 sec),
time use fastclock<br>
2.get the ratio between T3 count rise and charge
rise(total), fit it as charge=a+b*t3<br>
3.get the relationship between
(charge_per_sec-(a*t3_per_sec))/charge_per_sec<br>
The result is:<br>
by using run from 4234 to 4249, from 4/12/2012
14:24 to 4/12/2012 18:50, <br>
the result can be shown in attachment, t3ps is t3
count per second, upps is calibrated upstream bcm
charge per second, clk is from fastclock/103920,
unit is second<br>
the stability in 5 hours can be reach as 0.75%, less
than 1%, </div>
more data need to be replayed for study for more than
20hours.<br>
</div>
Is it what you want? Thanks!<font color="#888888"><br>
<div><br>
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<div>Pengjia</div>
</div>
</font>
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<div class="h5"> <br>
On 05/06/2013 04:51 AM, Jian-ping Chen wrote:<br>
</div>
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<div class="h5">
<blockquote type="cite"> Pengjia,<br>
<br>
The deadline for submitting the proposal is 8 am
Monday (US East time),<br>
Will need the inf on long-term (~20-24 hours)
stability for the BCM some hours<br>
before the deadline. We have only a few hours
left.let me know if you have anything.<br>
<br>
Thanks.<br>
<br>
Jian-ping<br>
<br>
<div>On 5/4/2013 5:16 AM, Pengjia wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div>Hi JP, Alex,<br>
</div>
I will figure it out as soon as possible,
Thanks!<br>
</div>
<div class="gmail_extra"><br clear="all">
<div>
<div>Pengjia</div>
</div>
<br>
<br>
<div class="gmail_quote">On Sat, May 4, 2013 at
5:56 AM, J. P. Chen <<a
moz-do-not-send="true"
href="mailto:jpchen@jlab.org">jpchen@jlab.org</a>>
wrote:<br>
<blockquote class="gmail_quote">
<div text="#000000" bgcolor="#FFFFFF"> Hi,
Pengjia and Alexandre,<br>
<br>
I need information on BCM for 100 nA.
Precision and stability.<br>
Also a question: do we reach 1%
(statistics) in less than 1 s?<br>
<br>
Thanks.<br>
<br>
Jian-ping
<div>
<div><br>
<br>
<div>On 5/3/2013 5:36 PM, Alexandre
Camsonne wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div>I guess you could normalize
by trigger rates too to correct
for beam fluctuations.<br>
<br>
</div>
Alexandre<br>
</div>
<div class="gmail_extra"><br>
<br>
<div class="gmail_quote">On Fri,
May 3, 2013 at 5:19 PM,
Alexandre Camsonne <<a
moz-do-not-send="true"
href="mailto:camsonne@jlab.org">camsonne@jlab.org</a>>
wrote:<br>
<blockquote class="gmail_quote">
<div dir="ltr">
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<div>
<div>
<div>Hi
Pengjia,<br>
<br>
</div>
JP would need
the accury to
which we
measure the
charged=<br>
at 50 nA.<br>
<br>
</div>
I need to look
back at the
data<br>
<br>
</div>
but I think we
have several
calibrations<br>
</div>
with the
calorimeter.<br>
<br>
</div>
Could you make a
plot of the
stability<br>
</div>
of the calibration
constants ?<br>
<br>
</div>
Also can you plot the
width of the measured
current ?<br>
<br>
</div>
And give the resolution
on the current we have :<br>
<br>
</div>
sigma / mean.<font
color="#888888"><br>
<br>
<br>
</font></div>
<font color="#888888">Alexandre<br>
</font></div>
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