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    <h2 class="entry-title">
      <a href="https://keflavich.github.io/blog/general-discussion-day-1.html" rel="bookmark"
         title="Permalink to General Discussion (Day 1)">General Discussion (Day 1)</a></h2>
 
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  <footer class="post-info">
    <abbr class="published" title="2013-09-30T17:05:00-06:00">
      2013/09/30
    </abbr>
    <address class="vcard author">
      By <a class="url fn" href="https://keflavich.github.io/blog/author/adam-ginsburg.html">Adam Ginsburg</a>
    </address>
  </footer><!-- /.post-info -->
  <div class="entry-content">
    <div class="section" id="large-scale">
<h2>Large-scale:</h2>
<blockquote>
<ul class="simple">
<li>Q: incomprehensible.</li>
<li><dl class="first docutils">
<dt>A Kim: turbulent nuclear rings are found... if angular momentum large... ring</dt>
<dd>can be very close to center</dd>
</dl>
</li>
<li>Q: Best guess for age of molecular torus in Herschel data?</li>
<li>A Kim: Simulations for external galaxies, didn't run for our Galaxy.</li>
<li>Q Morris: Asymmetry in distribution of molecular gas.  No asymmetry in
stellar distribution.  Implies m=1 mode / asymmetry in CMZ.  Has the
asymmetry been worked into models?</li>
<li>A Kim: ????</li>
</ul>
</blockquote>
<dl class="docutils">
<dt>[ I can barely understand this discussion ]</dt>
<dd><ul class="first last simple">
<li>Q: X1/X2; Kim sees mainly X2, but dust may be X1.  Does the ring form at transition?</li>
<li>A: No, rarely forms at transition radius.</li>
<li>Q: Weak bar case, lindlbad resonance is where x1/x2 change.  But with strong bar,
that approximation doesn't work.</li>
<li>A: Don't know if X2 orbits exist outside of inner lindblad resonance</li>
<li>Q: Dust lane on x1, ring on x2</li>
<li>Q: What is the filling factor of molecular gas in the inner region?</li>
<li>A Bally: 10%-30% very dense, with &quot;soup&quot; of low-density molecular gas.  H3+
indicates ionized molecular gas present.</li>
<li>Q Which phase dominates?</li>
<li>A Bally: Megakelvin plasma must fill the volume (X-ray measurements), thermal free-free emission,
plenty of ionized gas.  30-60% ionized gas filling factor</li>
<li>A Farhad: controversial what filling factor of mol gas is.  Oka, Geballe: 1%</li>
<li>A Geballe: 1% along <em>one</em> line of sight, towards Sgr A*</li>
<li>A John: Area filling factor is 1, volume filling factor is open question</li>
<li>Q Farhad: Twisted ring.  Problem with this idea.  Where is Sgr B2 w.r.t. X2 orbits?</li>
<li><dl class="first docutils">
<dt>A Bally: Sgr B2 is in the x2 orbit.  Not at apocenter yet, Sgr B2 not at</dt>
<dd>tangent point, still moving out.</dd>
</dl>
</li>
<li>Q Crocker: Radius for ring?</li>
<li>A Bally: 140, 150 pc?  At least a degree</li>
<li>A Longmore: I'll show tomorrow inner ~100 pc</li>
</ul>
</dd>
</dl>
</div>
<div class="section" id="smaller-scale">
<h2>Smaller Scale</h2>
<blockquote>
<ul class="simple">
<li>Q Longmore: What is the connection between the 100pc and 1pc ring?</li>
<li>A Ott: 20 km/s cloud is connected to the CND.  May be where molecular gas is exchanged</li>
<li>A Requen-Torres: John showed work from Rodriguez-Fernandez</li>
<li>A Bally: Streamers connected to CND.  Why's it called a disk?  It's a ring!</li>
<li>Q: What's the origin of the cirmnuclear disk?</li>
<li>A Bally: Matter that's losing angular momentum.  Dynamic friction, magnetic stresses, etc.</li>
<li>A Lacy: Suggestion of why gas drives into center....</li>
<li>A Kim: Collision between molecular clouds, B-fields too</li>
<li>A Morris: Room for controversy.  Transient feature because shear timescale
is short, but the CND seems to be in some sort of dynamical equilibrium.  Is
it long-lived, in which stabilities create clumps that are sheared out, or
if this is just an infalling cloud that has recently circularized.</li>
<li>Requen-Torres: Inclination, two different areas (disks?) inclined to each other</li>
<li>Q Any evidence for ring evaporation?</li>
</ul>
</blockquote>
<dl class="docutils">
<dt>[ most interesting point of the conference so far ]</dt>
<dd><ul class="first last simple">
<li>Q: Gas dynamics in Galactic center complicated... creates bias related to BH
mass.  How worried should we be about BH mass measurements using gas?</li>
<li>A Lacy: If we see gas preferentially at apocenter, we will underestimate BH mass</li>
</ul>
</dd>
</dl>
</div>

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