<div>Reminder: we start in half an hour. </div><div><br><div class="gmail_quote"><div>On Wed, Apr 26, 2017 at 10:50 AM Ragnar Stroberg <<a href="mailto:sstroberg@triumf.ca">sstroberg@triumf.ca</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>Hi all,<div><br></div><div>Here's a reminder that we're holding a journal club meeting at 3:30 in the MOB theory room.</div><div><br></div><div>Details are reprinted below.</div><div><br></div><div>See you there,</div><div><br></div><div>-Ragnar</div><div><br></div><div><div style="font-size:12.8px">The paper for this week is from the arxiv</div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><a href="https://arxiv.org/abs/1704.03785" target="_blank">https://arxiv.org/abs/1704.03785</a><br></div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px">(it's not yet published but it has obviously been submitted to PRL).</div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><b>Title:</b> Where is the neutron drip line for oxygen?</div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><b>Some questions to consider when reading:</b></div><div style="font-size:12.8px">1) What question are they trying to answer (if you can't figure this one out, you're not trying.)</div><div style="font-size:12.8px">2) What approach do they take, and what physics are they trying to incorporate that might not be in previous treatments?</div><div style="font-size:12.8px">3) Would you consider this approach phenomenological or ab initio?</div><div style="font-size:12.8px"><b><br></b></div><div style="font-size:12.8px"><b>Helpful background:</b></div><div style="font-size:12.8px">1) Neutron dripline: the heaviest isotope of a given element which is stable with respect to the emission of one or multiple neutrons.</div><div style="font-size:12.8px">2) History: the dripline of the oxygen at mass 24, is much lighter than was naively expected, especially considering that oxygen has a magic number of protons (Z=8). TRIUMF's very own Jason Holt provided an explanation of this anomaly by including the effects of 3-body forces. The existence of oxygen 28 has not yet been experimentally established.</div><div style="font-size:12.8px">3) Berggren basis: a single-particle basis consisting of bound, resonant, and continuum states.</div><div style="font-size:12.8px">4) Gamow Shell Model: a shell model calculation that uses the Berggren basis</div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><b>Questions for discussion:</b></div><div style="font-size:12.8px">1) When fitting 7 parameters to 7 or 8 observables, the obvious danger is overfitting. Do they make a compelling case that they aren't overfitting?</div><div style="font-size:12.8px">2) Are 3-body forces taken into account?</div><div style="font-size:12.8px">3) Does this study provide additional insight as to the location of the neutron drip line?</div><br clear="all"><div><br></div>-- <br><div class="m_1540564708599265276gmail_signature"><div>Ragnar Stroberg<div>Postdoctoral research associate<br><div>Theory Department</div></div><div>TRIUMF</div><div><span style="color:rgb(51,51,51);font-family:helveticaneue,helvetica,arial,sans-serif;font-size:12px;line-height:16.8px;text-align:-webkit-center">(604)-222-1047 x 6446</span><br></div><div><br></div></div></div></div></div>
</blockquote></div></div><div dir="ltr">-- <br></div><div data-smartmail="gmail_signature"><div dir="ltr">Ragnar Stroberg<div>Postdoctoral research associate<br><div>Theory Department</div></div><div>TRIUMF</div><div><span style="color:rgb(51,51,51);font-family:HelveticaNeue,Helvetica,Arial,sans-serif;font-size:12px;line-height:16.8px;text-align:-webkit-center">(604)-222-1047 x 6446</span><br></div><div><br></div></div></div>