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<p>Hello</p>
<p>On Friday the 22nd of April at 10:30, Mike Barlow (UCL) will be
giving our next seminar. This will be a hybrid seminar - you are
welcome to either attend in person in FC61 or via Zoom. Mike will
be visiting the department that Friday and we will be going for
lunch with him after the seminar.</p>
<p><b>Dust Formation by Supernovae</b><br>
<br>
The large quantities of dust found in a number of high redshift
galaxies has led to suggestions that core-collapse supernovae
(CCSNe) are the main sources of their dust and has motivated the
measurement of the dust masses formed by local and extragalactic
CCSNe. A widely used technique for CCSN dust mass determination,
namely the fitting of their optical-IR spectral energy
distributions, is restricted to warmer dust emitting shortwards of
30 microns by the lack of sufficiently sensitive facilities
operating at longer wavelengths. However, an alternative technique
for measuring total dust masses is available, one which is
insensitive to dust temperature. This method relies on the
spectral modelling of the red-blue asymmetries in late-epoch
optical emission line profiles, produced by dust within the ejecta
that selectively absorbs red-shifted photons emitted from the far
side of the ejecta. After reviewing earlier work on CCSN dust
masses, I will report on dust masses obtained from line profile
fitting for a large VLT and Gemini spectral survey of
extragalactic CCSNe, some observed at epochs up to 60 years after
outburst. Evidence will be presented for a slow growth in CCSN
ejecta dust masses with time, taking approximately 30 years to
saturate at a mean dust mass of 0.4 solar masses per CCSN.</p>
<p><br>
</p>
<p>Christopher Usher is inviting you to a scheduled Zoom meeting.
<br>
<br>
Topic: Astronomy Department Seminar
<br>
Time: Apr 22, 2022 10:30 AM Stockholm
<br>
<br>
Join Zoom Meeting
<br>
<a class="moz-txt-link-freetext" href="https://stockholmuniversity.zoom.us/j/69462418973">https://stockholmuniversity.zoom.us/j/69462418973</a>
<br>
<br>
Meeting ID: 694 6241 8973
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