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Reminder of the lunch talk at 1pm today!</div>
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Guillaume</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Guillaume Hewitt<br>
<b>Sent:</b> Monday, March 16, 2026 2:11 PM<br>
<b>To:</b> Nottingham Astro Group <astro@nottingham.ac.uk><br>
<b>Subject:</b> Lunch Talk - 19/03/2026</font>
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Hi everyone,</div>
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This week's lunch talk will be given by Fiona Sawyer on Thursday March 19<sup>th</sup> at 1pm in A113. Title and abstract are below.</div>
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<b>Title:</b> Uncovering the IGM temperature during reionisation with machine learning</div>
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<b>Abstract:</b> The thermal state of the IGM at high redshifts has the potential to serve as a useful probe of reionisation, providing information to help constrain, for example, the main drivers of reionisation through the thermal proximity effect around
quasars. While previous approaches have relied on summary statistics to measure IGM temperature, new machine learning methods will offer the opportunity to measure the underlying physical properties of the IGM (including its temperature) at a much higher
resolution. </div>
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In this talk, I will discuss my work on making a neural network to predict the temperature of the IGM during reionisation, within quasar proximity zones. We find a good recovery of the underlying physical parameters within errors, including when realistic noise
is added. I will also consider the challenges of moving from predicting on simulated data to observations and how well the network responds to them, paving the way for new temperature measurements during reionisation. </div>
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Cheers,</div>
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Guillaume</div>
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