<html><body><div style="color: rgb(0, 0, 0); font-family: arial,helvetica,sans-serif; font-size: 12pt;"><div><hr id="zwchr" data-marker="__DIVIDER__"></div><div data-marker="__HEADERS__"><b>From: </b>"cbaker" <cbaker@jlab.org><br><b>Sent: </b>Thursday, February 19, 2015 3:57:19 PM<br><b>Subject: </b>ODU CAS seminar- February 26th<br></div><div><br></div><div data-marker="__QUOTED_TEXT__"><div class="moz-cite-prefix"><div lang="x-western" class="moz-text-html"><div><span style="font-size: medium; background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff; font-size: medium;">Dear Colleagues:</span></div><div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" data-mce-style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" data-mce-style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"><span style="font-size: medium;" data-mce-style="font-size: medium;" size="3"><br> </span></span></div><div><span style="font-size: medium;" data-mce-style="font-size: medium;" size="3">We will have our next CAS seminar on Thursday Feb. 26 at 1:30 at ODU in the CAS building (see below). There will also be a video link for the talk at<span style="color: rgb(227, 36, 0);" data-mce-style="color: #e32400;" color="#e32400"> Jefferson Lab in the ARC building in room 728. </span>Refreshments will be available at ODU at 1 pm. The schedule for future talks is listed at the end of this message. If you want to be added to this email distribution list, please let me know.</span></div><span style="color: rgb(227, 36, 0);" data-mce-style="color: #e32400;" color="#e32400"><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"></span></span><p style="text-align: left;" class="MsoNormal" align="center" data-mce-style="text-align: left;"><span style="font-size: 25px;" data-mce-style="font-size: 25px;"><span style="color: rgb(227, 36, 0);" data-mce-style="color: #e32400;" color="#e32400">Positron Sources, Applications and the PEPPo Experiment</span></span><span style="font-size: 16pt;" data-mce-style="font-size: 16pt;"></span></p><div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" data-mce-style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" data-mce-style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><span style="font-size: 25px;" data-mce-style="font-size: 25px;"> <span style="white-space: pre;" class="Apple-tab-span" data-mce-style="white-space: pre;"> </span><span style="color: rgb(0, 97, 255);" data-mce-style="color: #0061ff;" color="#0061ff">Dr.</span> <span style="color: rgb(0, 97, 255);" data-mce-style="color: #0061ff;" color="#0061ff">Joe Grames</span></span></div><div><span style="text-align: center; font-size: 16pt;" data-mce-style="font-size: 16pt; text-align: center;"><span style="white-space: pre;" class="Apple-tab-span" data-mce-style="white-space: pre;"></span>Center for Injectors and Sources</span></div><div><span style="color: rgb(0, 97, 255); font-size: x-large;" data-mce-style="color: #0061ff; font-size: x-large;" size="5" color="#0061ff"> <span style="white-space: pre;" class="Apple-tab-span" data-mce-style="white-space: pre;"> </span></span><span style="font-size: 20px;" data-mce-style="font-size: 20px;">Jefferson Laboratory</span></div><div style="font-size: 13px;" data-mce-style="font-size: 13px;"><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"><br> </span></div><div><span style="font-size: large;" data-mce-style="font-size: large;" size="4"><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;">When: Thursday Feb. 26, 2015; 1:30 pm </span><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;">(<span style="color: rgb(227, 36, 0);" data-mce-style="color: #e32400;" color="#e32400">Refreshments at 1 pm</span>)</span></span></div><div><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"><span style="font-size: large;" data-mce-style="font-size: large;" size="4">Where: CAS Building at ODU (1021 W. 47th St.)</span></span></div><div><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"><span style="font-size: large;" data-mce-style="font-size: large;" size="4">Video: Jefferson Lab ARC 728 and Jefferson Lab MCC Conference Room <br> </span></span></div><div style="font-size: 13px;" data-mce-style="font-size: 13px;"><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"><br> </span></div><div><b style="font-size: 18px;" data-mce-style="font-size: 18px;">Abstract: </b><span style="font-size: large;" data-mce-style="font-size: large;" size="4"> </span><p style="text-align: justify; text-justify: inter-ideograph;" class="MsoNormal" data-mce-style="text-align: justify; text-justify: inter-ideograph;"><span style="font-size: 14pt; mso-bidi-font-size: 12.0pt;" data-mce-style="font-size: 14.0pt; mso-bidi-font-size: 12.0pt;">The positron is the anti-matter counterpart of the electron. Produced either by the weak interaction in unstable nuclei or by pair production from photons of sufficient energy impinging matter, it is a ubiquitous component for endeavors spanning materials science, medical imaging and particle physics. In this seminar a variety of applications requiring positrons from very low (eV) to very high (TeV) energies will be mentioned. Technical features and challenges of positron sources and beams formed from them will be surveyed, and the R&D considerations for a positron source at Jefferson Lab discussed.</span></p><p style="text-align: justify; text-justify: inter-ideograph;" class="MsoNormal" data-mce-style="text-align: justify; text-justify: inter-ideograph;"><span style="font-size: 14pt; mso-bidi-font-size: 12.0pt;" data-mce-style="font-size: 14.0pt; mso-bidi-font-size: 12.0pt;">A highlight of the R&D that will be featured in some detail is a recent proof-of-principle experiment performed at CEBAF demonstrating a new method to produce polarized positrons. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e-/e+ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high atomic number conversion target. The experiment demonstrated the effective transfer of spin from a highly-polarized 8.2 MeV/c polarized electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for high energy or thermal polarized positron beams that can be generated using a polarized electron beam of relatively low energy < 10MeV.</span></p><span style="font-size: 18px; background-color: rgb(255, 255, 255);" data-mce-style="font-size: 18px; background-color: #ffffff;">__________________________________________________________</span></div><div style="font-size: 13px;" data-mce-style="font-size: 13px;"><span style="font-size: 18px; background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff; font-size: 18px;"><span style="color: rgb(63, 62, 255);" data-mce-style="color: #3f3eff;" color="#3f3eff">Future Speakers:</span></span></div><div style="font-size: 13px;" data-mce-style="font-size: 13px;"><span style="font-size: large;" data-mce-style="font-size: large;">Mar. 26: Janardan Upadhyay</span></div></div></div><div><div style="font-size: 13px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" data-mce-style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; font-size: 13px;"><br></div></div></div></div></div></div></div><div><span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"><br> </span></div><div><span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"><br> </span></div><span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">---------------------------------------</span><br><div><div><span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">Gail Dodge</span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">Department of Physics</span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">Old Dominion University</span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">Norfolk, VA 23529</span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"><a href="mailto:gdodge@odu.edu" target="_blank" data-mce-href="mailto:gdodge@odu.edu">gdodge@odu.edu</a></span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">office: (757) 683-5854</span><br style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;"> <span style="orphans: 2; widows: 2;" data-mce-style="orphans: 2; widows: 2;">fax: (757) 683-3038</span></div></div><br></div></div><br></div></div></body></html>