{"id":511,"date":"2018-11-20T16:06:17","date_gmt":"2018-11-20T16:06:17","guid":{"rendered":"https:\/\/research.kent.ac.uk\/beta-caps\/?p=511"},"modified":"2021-07-28T00:27:28","modified_gmt":"2021-07-27T23:27:28","slug":"seminar-by-dr-ahmad-ali","status":"publish","type":"post","link":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/2018\/11\/20\/seminar-by-dr-ahmad-ali\/","title":{"rendered":"Seminar by Dr Ahmad Ali"},"content":{"rendered":"<p>Dr Ahmad Ali recently completed his PhD in theoretical astrophysics at the University of Exeter, focusing on the numerical modelling of massive stars. Dr Ali is now carrying out his post-doctoral research at Exeter and visited Kent on 20-21 November, to present a research seminar about his current work. He is also collaborating with Justyn Campbell-White, one of the PhD students at Kent. They are using the synthetic observations from Dr Ali&#8217;s numerical models to compare the results from simulations to radio-continuum observations of massive stellar feedback in the Galaxy.<\/p>\n<p><strong>Abstract<\/strong><\/p>\n<div class=\"\">The thermodynamics of star-forming molecular clouds is dominated by O stars via their radiative feedback. This can affect the formation of new stars: triggering it via gas compression, or inhibiting it via gas dispersal. Numerical simulations provide a way to constrain the relative impact of different feedback mechanisms, explore their dependence on initial conditions, and test observational diagnostics via synthetic observations.<\/div>\n<div class=\"\"><\/div>\n<div class=\"\">In this talk, I describe how to investigate these processes using Monte Carlo radiative transfer coupled with hydrodynamics. I describe the results of modelling turbulent clouds of 1000 and 10,000 Msol, containing a 34 Msol star, with accurate photoionisation and radiation pressure feedback. The models also include detailed dust microphysics such as absorption and scattering.<\/div>\n<div><\/div>\n<div class=\"\">\n<div><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-514\" src=\"https:\/\/research.kent.ac.uk\/beta-caps\/wp-content\/uploads\/sites\/1967\/2018\/12\/Ali-et-al.-2018-MNRAS-1024x601.png\" alt=\"\" width=\"1024\" height=\"601\" srcset=\"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-content\/uploads\/sites\/1967\/2018\/12\/Ali-et-al.-2018-MNRAS-1024x601.png 1024w, https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-content\/uploads\/sites\/1967\/2018\/12\/Ali-et-al.-2018-MNRAS-300x176.png 300w, https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-content\/uploads\/sites\/1967\/2018\/12\/Ali-et-al.-2018-MNRAS-768x451.png 768w, https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-content\/uploads\/sites\/1967\/2018\/12\/Ali-et-al.-2018-MNRAS.png 1380w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div>\n<div><\/div>\n<\/div>\n<div class=\"\">Using the resulting gas temperatures, dust temperatures, and ionisation fractions, I also present self-consistent synthetic observations of line and continuum emission (e.g. Halpha and free-free radio continuum). I also track the complex behaviour of the FUV interstellar radiation field, G0, as a function of time and distance from the O star; this shows rapid variations of orders of magnitude across time-scales of a ~Myr, and will therefore influence the evolution of clumps and protoplanetary discs near O stars.<\/div>\n<div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Dr Ahmad Ali recently completed his PhD in theoretical astrophysics at the University of Exeter, focusing on the numerical modelling of massive stars. Dr Ali is now carrying out his post-doctoral research at Exeter and visited Kent on 20-21 November, to present a research seminar about his current work. He is also collaborating with Justyn [&hellip;]<\/p>\n","protected":false},"author":456,"featured_media":520,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[602],"tags":[],"class_list":["post-511","post","type-post","status-publish","format-standard","hentry","category-colloquia"],"acf":[],"_links":{"self":[{"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/posts\/511","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/users\/456"}],"replies":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/comments?post=511"}],"version-history":[{"count":2,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/posts\/511\/revisions"}],"predecessor-version":[{"id":522,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/posts\/511\/revisions\/522"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/media\/520"}],"wp:attachment":[{"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/media?parent=511"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/categories?post=511"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/research.kent.ac.uk\/astrophysics-and-planetary-science\/wp-json\/wp\/v2\/tags?post=511"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}