<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.MsoPlainText, li.MsoPlainText, div.MsoPlainText
{mso-style-priority:99;
mso-style-link:"Plain Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
span.PlainTextChar
{mso-style-name:"Plain Text Char";
mso-style-priority:99;
mso-style-link:"Plain Text";
font-family:"Calibri",sans-serif;}
span.value
{mso-style-name:value;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<div style="mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.5pt;padding:0in 0in 1.0pt 0in">
<p class="MsoNormal" align="center" style="text-align:center;border:none;padding:0in">
<b><span style="font-size:48.0pt;font-family:"Times New Roman",serif">Physics Seminar<o:p></o:p></span></b></p>
</div>
<p class="MsoNormal" align="center" style="text-align:center"><span class="value"><b><span style="font-size:22.0pt;font-family:"Times New Roman",serif">Ashot Gasparian<o:p></o:p></span></b></span></p>
<p class="MsoNormal" align="center" style="text-align:center"><span class="value"><span style="font-size:22.0pt"><o:p> </o:p></span></span></p>
<p class="MsoNormal" align="center" style="text-align:center"><span class="value"><b><span style="font-size:20.0pt;font-family:"Times New Roman",serif">NC A&T State University for the PrimEx Collaboration</span></b></span><span style="font-size:20.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><b><i><span style="font-family:"Times New Roman",serif"><o:p> </o:p></span></i></b></p>
<p class="MsoPlainText" align="center" style="text-align:center"><i><span style="font-size:20.0pt;font-family:"Times New Roman",serif">The Neutral Pion Life Time: Final Result from the PrimEx Experiments<o:p></o:p></span></i></p>
<p class="MsoPlainText" align="center" style="text-align:center"><i><span style="font-size:22.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></i></p>
<p class="MsoPlainText" align="center" style="text-align:center"><b><span style="font-size:18.0pt;font-family:"Times New Roman",serif">Abstract:</span></b><span style="font-family:"Times New Roman",serif"><o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:14.0pt;font-family:"Times New Roman",serif">The neutral pion is the lightest strongly interacting particle in Nature. Therefore, the properties of Ο0 decay are especially sensitive to the underlying fundamental
symmetries of quantum chromodynamics (QCD). In particular, the Ο0 β </span><span style="font-size:14.0pt;font-family:"Cambria Math",serif">πΎπΎ</span><span style="font-size:14.0pt;font-family:"Times New Roman",serif"> decay width is primarily defined by the
chiral anomaly, a fundamental symmetry breaking effect in QCD. Theoretical activities in this domain over the past years resulted in a high precision (1% level) prediction for the Ο0β
</span><span style="font-size:14.0pt;font-family:"Cambria Math",serif">πΎπΎ</span><span style="font-size:14.0pt;font-family:"Times New Roman",serif"> decay width. The PrimEx collaboration has developed and performed two new experiments to measure the Ο0 β
</span><span style="font-size:14.0pt;font-family:"Cambria Math",serif">πΎπΎ</span><span style="font-size:14.0pt;font-family:"Times New Roman",serif"> decay width with high precision using the Primakoff effect. The published result from the first experiment
(PrimEx-I) was a factor of two more precise than the PDG accepted average value, and was in a good agreement with the chiral anomaly prediction. The second experiment (PrimEx-II) was performed in 2010 with a goal of 1.4% total uncertainty to address the next-to-leading-order
chiral perturbation theory calculations. The final results from the PrimEx experiments will be presented and discussed in this talk.<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-family:"Times New Roman",serif"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoNormal" align="center" style="text-align:center"><b><span style="font-size:18.0pt">Friday, February 8, 2019<o:p></o:p></span></b></p>
<p class="MsoNormal" align="center" style="text-align:center"><b><span style="font-size:18.0pt">11:00 am<o:p></o:p></span></b></p>
<p class="MsoNormal" align="center" style="text-align:center"><b><span style="font-size:18.0pt">CEBAF Center Auditorium<o:p></o:p></span></b></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Stephanie Tysor<o:p></o:p></p>
<p class="MsoNormal">Thomas Jefferson National Accelerator Facility<o:p></o:p></p>
<p class="MsoNormal">Physics Division<o:p></o:p></p>
<p class="MsoNormal">Hall A Administrative Assistant<br>
(office)<a href="callto:757-269-6005"><span style="color:blue">757-269-6005</span></a> (fax)<a href="callto:757-269-5235"><span style="color:blue">757-269-5235</span></a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</body>
</html>