{"id":4220,"date":"2018-01-11T00:20:07","date_gmt":"2018-01-10T20:20:07","guid":{"rendered":"http:\/\/sites.williams.edu\/kkwitter\/?page_id=4220"},"modified":"2018-02-08T20:17:46","modified_gmt":"2018-02-08T16:17:46","slug":"a402t-tutorial-week-6-thermal-equilibrium","status":"publish","type":"page","link":"https:\/\/sites.williams.edu\/kkwitter\/astronomy-402-between-the-stars\/a402t-tutorial-week-6-thermal-equilibrium\/","title":{"rendered":"A402T Tutorial Week #6: Thermal Equilibrium"},"content":{"rendered":"<p><strong>ASTRONOMY 402T \u2013 Spring 2018<br \/>\nProblems for Tutorial Week #6<\/strong><\/p>\n<p><strong>PART A<\/strong><\/p>\n<p><strong>1.<\/strong>\u00a0a) Enumerate the possible ways a nebula can have a net gain or loss in energy.<\/p>\n<p>b) What processes can shuffle energy around in the nebula but\u00a0<strong>not<\/strong> lead to a net energy loss.<\/p>\n<div class=\"hidden\">Think in particular about i) hydrogen recombination to the ground state; and ii) Lyman \u03b1 emission.<\/div>\n<p><strong>2.\u00a0<\/strong>In the 1940&#8217;s it was noticed that for H II regions in the spiral galaxy M33, the strengths of the [O III] \u03bb\u03bb 4959, 5007 lines\u00a0relative to H\u03b2 increased as the distance of the H II region from the center of M33 increased. In addition, the nebular temperature likewise increased with increasing distance. We now know that the abundance of metals in a spiral galaxy generally decreases with distance from the center. How does this explain what was seen in M33? Be specific and as quantitative as possible.<\/p>\n<p><strong>PART B<\/strong><\/p>\n<p><strong>Do the PN Gallery <em>\u201cEmission Lines and Central Star Temperature\u201d <\/em>exercise: <\/strong><\/p>\n<p><strong><a href=\"http:\/\/web.williams.edu\/Astronomy\/research\/PN\/nebulae\/exercise1.php\">http:\/\/web.williams.edu\/Astronomy\/research\/PN\/nebulae\/exercise1.php<\/a><\/strong><\/p>\n<p><strong>\u00a0<\/strong><strong>PART C<\/strong><\/p>\n<p><strong><a href=\"http:\/\/sites.williams.edu\/kkwitter\/files\/2018\/02\/ESA_PNdist_class.pdf\" target=\"new\">ESA Exercise: Distance to the Cat&#8217;s Eye Nebula<\/a><\/strong><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ASTRONOMY 402T \u2013 Spring 2018 Problems for Tutorial Week #6 PART A 1.\u00a0a) Enumerate the possible ways a nebula can have a net gain or loss in energy. b) What processes can shuffle energy around in the nebula but\u00a0not lead to a net energy loss. Think in particular about i) hydrogen recombination to the ground [&hellip;]<\/p>\n","protected":false},"author":198,"featured_media":0,"parent":793,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-4220","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/pages\/4220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/users\/198"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/comments?post=4220"}],"version-history":[{"count":11,"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/pages\/4220\/revisions"}],"predecessor-version":[{"id":4378,"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/pages\/4220\/revisions\/4378"}],"up":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/pages\/793"}],"wp:attachment":[{"href":"https:\/\/sites.williams.edu\/kkwitter\/wp-json\/wp\/v2\/media?parent=4220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}