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Hi all, <br>
<br>
We will have our last PASS talk of the quarter tomorrow. Please join
us at noon (from 12:00 pm to 1:00 pm) in the Nebula Room (PHYS
3027).<br>
<br>
<br>
<div align="center">Yash Aggarwal, PhD student<br>
<br>
Monday, 12:00 pm, Nebula Room (PHYS 3027)<br>
Constraining Axion-Like Particles Using Direct Collapse Black
Holes. <br>
<br>
<br>
Cosmic Dawn is the new pathway for Dark Matter indirect detection.
During this era, axion-like particles may decay into sub-Lyman
limit photons with energies ranging from 0.75 eV to 13.6 eV. These
photons efficiently suppress and dissociate molecular hydrogen
(H₂), the primary coolant for first star-forming halos. Without
molecular coolants, halos reaching the 10⁴ K threshold can only
cool via atomic hydrogen, and are driven towards the formation of
Direct Collapse Black Holes (DCBHs). We demonstrate that
sufficient axion decay pushes halos along the DCBH route globally,
thereby presenting a part of parameter space that must be excluded
to maintain consistency with the observed Universe. <br>
</div>
<br>
<br>
If you’re interested in sharing your work as a speaker, please feel
free to add your name to this spreadsheet [<a
href="https://docs.google.com/spreadsheets/d/1N3ncf43jdB6aHYHhyWmyHMycxDg4_phHZXLkQvviO0o/edit?usp=sharing">Google
Sheet</a>].<br>
<br>
Best,<br>
Pooyan<br>
Physics and Astronomy Student Seminar (PASS)<br>
<br>
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