<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=koi8-r">
<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);">
Matt,</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);">
Where is stored the real threshold in the database? <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);">
tks ig.<br>
</div>
<div id="appendonsend"></div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Shepherd, Matthew <mashephe@indiana.edu><br>
<b>Sent:</b> Thursday, May 14, 2020 1:26 PM<br>
<b>To:</b> Igal Jaegle <ijaegle@jlab.org><br>
<b>Cc:</b> Ilya Larin <ilarin@jlab.org>; Ashot Gasparian <agaspari@ncat.edu>; primexd@jlab.org <primexd@jlab.org>; Liping Gan <ganl@uncw.edu><br>
<b>Subject:</b> [EXTERNAL] Re: [Primexd] Question</font>
<div> </div>
</div>
<div class="" style="word-wrap:break-word; line-break:after-white-space">
<div class=""><br class="">
</div>
<div class="">Hi all,</div>
<div class=""><br class="">
</div>
<div class="">I would argue that you should take an approach that is driven by the need to solve problems. I think this is what Sasha was advocating for. As you know manpower is very limited.</div>
<div class=""><br class="">
</div>
<div class="">Regarding this specific discussion, we attempt to use the method Ilya sketches, but as Igal points out, the energy scales and variations are larger. Certainly by putting a fixed threshold you can simulate the cut better, but one needs to be sure
the distribution of the variable being cut is also properly simulated. We've attempted to do that, but then stopped short of putting the cut in the argument that it is bad to throw away information.</div>
<div class=""><br class="">
</div>
<div class="">Sometimes you must throw away information to ensure reproducibility in simulation -- this is the essence of fiducial cuts.</div>
<div class=""><br class="">
</div>
<div class="">We can debate back and forth the pros and cons of all approaches, but it is kind of an academic discussion. If I were in your position, I would try to look for biggest problems or systematic sensitivities in the simulation. As Sasha said, this
can be done by looking at variations of extracted Compton under a variety of different choices in the analysis. Then when a signficant effect is observed try to drill down all the way to the root cause, maybe as far as things like Ashot was suggesting to
try to control/calibrate gains of PMTs based on LED system. </div>
<div class=""><br class="">
</div>
<div class="">I think if you don't pursue a pragmatic strategy like this, there is risk of consuming significant manpower to create an alternative simulation approach that, while completely justified and may be similar to that used in other experiments, does
not result in a significant reduction of systematic error. And then you'll have to spend time fixing the real systematics limitations when they arise.</div>
<div class=""><br class="">
</div>
<div class="">That's just my two cents -- which may not even be worth two cents!</div>
<div class=""><br class="">
</div>
<div class="">Cheers and I enjoyed the opportunity to talk about this at length yesterday afternoon.</div>
<div class=""><br class="">
</div>
<div class="">Matt</div>
<div class=""><br class="">
</div>
<br class="">
<div><br class="">
<blockquote type="cite" class="">
<div class="">On May 14, 2020, at 1:05 PM, Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>> wrote:</div>
<br class="x_Apple-interchange-newline">
<div class="">
<div class="" style="font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Thank you Ilya, for the clarification as the threshold in FCAL is 25 times higher with a 5 MeV RMS from channel to channel, should we chose the same approach i.e. set the threshold at the lowest possible values or try to uniform it for most channels? What do
you think?<br class="">
</div>
<div class="" style="font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<div class="" style="font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
tks ig.<br class="">
</div>
<div id="x_appendonsend" class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
</div>
<hr tabindex="-1" class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; display:inline-block; width:718.328125px">
<span class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; float:none; display:inline!important"></span>
<div id="x_divRplyFwdMsg" dir="ltr" class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
<font face="Calibri, sans-serif" class="" style="font-size:11pt"><b class="">From:</b><span class="x_Apple-converted-space"> </span>Ilya Larin <<a href="mailto:ilarin@jlab.org" class="">ilarin@jlab.org</a>><br class="">
<b class="">Sent:</b><span class="x_Apple-converted-space"> </span>Thursday, May 14, 2020 12:56 PM<br class="">
<b class="">To:</b><span class="x_Apple-converted-space"> </span>Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>>; Ashot Gasparian <<a href="mailto:agaspari@ncat.edu" class="">agaspari@ncat.edu</a>>;
<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a> <<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a>>; Gan, Liping <<a href="mailto:ganl@uncw.edu" class="">ganl@uncw.edu</a>><br class="">
<b class="">Subject:</b><span class="x_Apple-converted-space"> </span>RE: Question</font>
<div class=""> </div>
</div>
<div dir="ltr" class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
that was read from the table,</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
it was about 3-5 counts and a count was approximately 1 MeV.</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Ilya<br class="">
</div>
<div class="">
<div id="x_x_appendonsend" class=""></div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<hr tabindex="-1" class="" style="display:inline-block; width:718.328125px">
<div id="x_x_divRplyFwdMsg" dir="ltr" class=""><font face="Calibri, sans-serif" class="" style="font-size:11pt"><b class="">От:</b><span class="x_Apple-converted-space"> </span>Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>><br class="">
<b class="">Отправлено:</b><span class="x_Apple-converted-space"> </span>14 мая 2020 г. 12:54<br class="">
<b class="">Кому:</b><span class="x_Apple-converted-space"> </span>Ilya Larin <<a href="mailto:ilarin@jlab.org" class="">ilarin@jlab.org</a>>; Ashot Gasparian <<a href="mailto:agaspari@ncat.edu" class="">agaspari@ncat.edu</a>>;
<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a> <<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a>>; Gan, Liping <<a href="mailto:ganl@uncw.edu" class="">ganl@uncw.edu</a>><br class="">
<b class="">Тема:</b><span class="x_Apple-converted-space"> </span>Re: Question</font>
<div class=""> </div>
</div>
<div dir="ltr" class="">
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Thank you, Ilya, What was this threshold in MeV and by how much it was varying from channel to channel?</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
tks ig.<br class="">
</div>
<div id="x_x_x_appendonsend" class=""></div>
<hr tabindex="-1" class="" style="display:inline-block; width:718.328125px">
<div id="x_x_x_divRplyFwdMsg" dir="ltr" class=""><font face="Calibri, sans-serif" class="" style="font-size:11pt"><b class="">From:</b><span class="x_Apple-converted-space"> </span>Ilya Larin <<a href="mailto:ilarin@jlab.org" class="">ilarin@jlab.org</a>><br class="">
<b class="">Sent:</b><span class="x_Apple-converted-space"> </span>Thursday, May 14, 2020 12:50 PM<br class="">
<b class="">To:</b><span class="x_Apple-converted-space"> </span>Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>>; Ashot Gasparian <<a href="mailto:agaspari@ncat.edu" class="">agaspari@ncat.edu</a>>;
<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a> <<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a>>; Gan, Liping <<a href="mailto:ganl@uncw.edu" class="">ganl@uncw.edu</a>><br class="">
<b class="">Subject:</b><span class="x_Apple-converted-space"> </span>RE: Question</font>
<div class=""> </div>
</div>
<div dir="ltr" class="">
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Hi Igal,</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
in the PrimEx simulations, we just add electronics noise first,</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
then cut the channel signal at our sparcification threshold:</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
whatever is below - set to zero.</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Ilya<br class="">
</div>
<div class="">
<div id="x_x_x_x_appendonsend" class=""></div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<hr tabindex="-1" class="" style="display:inline-block; width:718.328125px">
<div id="x_x_x_x_divRplyFwdMsg" dir="ltr" class=""><font face="Calibri, sans-serif" class="" style="font-size:11pt"><b class="">От:</b><span class="x_Apple-converted-space"> </span>Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>><br class="">
<b class="">Отправлено:</b><span class="x_Apple-converted-space"> </span>14 мая 2020 г. 12:46<br class="">
<b class="">Кому:</b><span class="x_Apple-converted-space"> </span>Ashot Gasparian <<a href="mailto:agaspari@ncat.edu" class="">agaspari@ncat.edu</a>>;
<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a> <<a href="mailto:primexd@jlab.org" class="">primexd@jlab.org</a>>; Ilya Larin <<a href="mailto:ilarin@jlab.org" class="">ilarin@jlab.org</a>>; Gan, Liping <<a href="mailto:ganl@uncw.edu" class="">ganl@uncw.edu</a>><br class="">
<b class="">Тема:</b><span class="x_Apple-converted-space"> </span>Question</font>
<div class=""> </div>
</div>
<div dir="ltr" class="">
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Liping, Ilya, Ashot,</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
Currently, in the MC simulation, the energy threshold for a detector to be included in a cluster is calculated from the data gains ie it is varying from detector to detector and is run-dependent. To minimize the systematics should we leave the situation as
it is or think of a different approach. I am thinking (naively) that it might be better to set this threshold to value at least 20 to 30% to what it is actually and possibly to set the threshold in a way that is the same for most detectors, and all runs both
in data and simulation. What are your inputs in this or what did you do in previous PRIMEX measurements?</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
<br class="">
</div>
<div class="" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">
tks ig. <span class="x_Apple-converted-space"> </span><br class="">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<span class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; float:none; display:inline!important">_______________________________________________</span><br class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
<span class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; float:none; display:inline!important">Primexd
mailing list</span><br class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
<span class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; float:none; display:inline!important"><a href="mailto:Primexd@jlab.org" class="">Primexd@jlab.org</a></span><br class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none">
<span class="" style="font-family:Helvetica; font-size:12px; font-style:normal; font-variant-caps:normal; font-weight:normal; letter-spacing:normal; text-align:start; text-indent:0px; text-transform:none; white-space:normal; word-spacing:0px; text-decoration:none; float:none; display:inline!important"><a href="https://mailman.jlab.org/mailman/listinfo/primexd" class="">https://mailman.jlab.org/mailman/listinfo/primexd</a></span></div>
</blockquote>
</div>
<br class="">
</div>
</body>
</html>