[Physics-grads-open] [physics-grads-open] Physics & Astronomy Student Seminar (PASS), May 23rd at 4 pm, Phys 3027

[Ming-Feng Ho]

Hi all!

We had a very fruitful PASS seminar last week. This week we have Yongda Zhu
(4th year PhD) as our speaker for PASS:

*Title: Probing Cosmic Reionization Using Hydrogen Absorption Lines*

Yongda Zhu (University of California, Riverside)

*Abstracts:* Reionization is the last major phase transition in the history
of the Universe. During the epoch of reionization, which is widely believed
to occur between roughly 150 million and one billion years after the Big
Bang (redshift 20 ≳ z ≳ 6), neutral hydrogen in the intergalactic medium
(IGM) was ionized by ultraviolet (UV) photons emitted by the first
generations of stars and galaxies. The timing of reionization is therefore
essential for us to understand the formation and evolution of the first
galaxies.
Large-scale fluctuations in IGM Lyman-alpha opacity at z < 6 suggest that
reionization may have ended later than is normally assumed. Alternatively,
the opacity fluctuations may be driven by variations in the ionizing UV
background that reionization has ended. To resolve this dilemma, we can use
hydrogen absorption lines in quasar spectra to probe the IGM during the
reionization epoch. In this talk, I will present the novel investigations
of the IGM over 5 < z < 6 using dark gaps in the Lyman-ɑ&Lyman-β forest. I
will show our latest results and discuss the implications for reionization.

Monday, May 23, 2022 at 4 pm
Physics 3027 (Nebula Room)

Details of the PASS program, please find here [Program
<https://jibancat.github.io/ucr-student-seminars/program/index.html>].

We have presenters scheduled until the end of the Spring Quarter (May 30
Wei-Xiang Feng, June 6 Pak Kau Lim). And three more presenters (Mahdi
Qezlou, Reza Monadi, and Elizabeth Finney) are queued in the Summer Quarter.

To submit abstracts for Summer Quarter: [Abstract Submission
<https://jibancat.github.io/ucr-student-seminars/registration/index.html>].

Hope to see you there!
Ming-Feng
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.ucr.edu/pipermail/physics-grads-open/attachments/20220520/03f7d4c9/attachment.html>