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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> secr-astro-science <secr-astro-science@uva.nl>
<br>
<b>Sent:</b> maandag 9 oktober 2023 09:24<br>
<b>Subject:</b> [Api-colloq] Colloquium this week<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><i><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif">Guest:
<span style="color:black">Aditya Parthasarathy</span></span></i><o:p></o:p></p>
<p class="xmsonormal"><i><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif">Host: Anna Watts</span></i><o:p></o:p></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif"> </span></b><o:p></o:p></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif">The first inroads into the low-frequency gravitational wave spectrum </span></b><o:p></o:p></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif">Supermassive black holes at the centres of merging galaxies are expected to form binary systems whose orbital motion generates gravitational waves. A cosmological
population of such systems combine to build up a gravitational wave background (GWB). A significant detection of this GWB will provide the first stringent constraints on the dynamical evolution of supermassive black holes and their host galaxies while also
providing a tantalising probe into the properties of the early Universe. Searches for the GWB have typically used sensitive radio telescopes around the world which observe an ensemble of extremely stable millisecond pulsars to probe the characteristics of
the GWB signal. In this talk, I will discuss the first compelling evidence of the GWB seen by global pulsar timing array (PTA) collaborations as announced this year, its scientific impact, potential biases and the road ahead. Focussing on future advancements,
I will talk about the powerful potential of a gamma-ray PTA and how it can improve our understanding of the astrophysical origins of the GWB.</span><o:p></o:p></p>
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<p class="MsoNormal"><i><span lang="EN-CA" style="font-size:14.0pt;font-family:"Tahoma",sans-serif;color:black">Date and Time: Wednesday, October 11<sup>th</sup>, 2023, at 11.00 CEST<br>
Place : C4.174</span></i><o:p></o:p></p>
<p class="MsoNormal"><i><span lang="EN-CA" style="font-size:14.0pt;font-family:"Tahoma",sans-serif"> </span></i><o:p></o:p></p>
<p class="MsoNormal"><b><i><span lang="EN-CA" style="font-size:14.0pt;font-family:"Tahoma",sans-serif;color:black">Join Zoom Meeting:
</span></i></b><i><span style="font-size:14.0pt;font-family:"Tahoma",sans-serif"><a href="https://uva-live.zoom.us/j/83709961721"><span lang="EN-US" style="color:#1155CC">https://uva-live.zoom.us/j/83709961721</span></a></span></i><o:p></o:p></p>
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<p class="MsoNormal"><i><span lang="EN-US" style="font-size:14.0pt;font-family:"Tahoma",sans-serif;color:black">Discussion sign-up sheet:
<a href="https://docs.google.com/document/d/1msKGkmFnX1jX_Ar_5Kha2aKlLyw_Ijgje5I3fAYZRD4/edit?usp=sharing">
https://docs.google.com/document/d/1msKGkmFnX1jX_Ar_5Kha2aKlLyw_Ijgje5I3fAYZRD4/edit?usp=sharing</a></span></i><o:p></o:p></p>
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