<div dir="ltr"><div>Happening in ~15 minutes.</div><div><br></div><div style="text-align:center"><br></div><div><div dir="auto" style="text-align:center"><b>Andrew Weldon</b>, <b>PhD Candidate</b></div><div dir="auto" style="text-align:center"><b>Friday, 1:00 pm, Conference Room (PHYS 3051)</b> </div><div dir="auto" style="text-align:center"><br></div><div dir="auto" style="text-align:center"><br></div><div dir="auto" style="text-align:center"><br></div><div dir="auto" style="text-align:center">The
Properties of Gas Flows and their Connection to z ~ 2 Star-forming
Galaxies
Abstract:
The physical processes that govern the evolution of galaxies are
dictated by the cycling of gas into and out of galaxies. The incidence
rate and effects of these gas flows are expected to be common and
pronounced at redshifts of z ~ 2, the peak of star-formation rate and
quasar activity in the history of the Universe. However, there are few
direct observational constraints on the properties of outflows in
individual galaxies during this epoch. Here, I combine rest-UV and
rest-optical spectroscopy to characterize the cool, low-ionized and
warm, ionized gas outflow phases from star-forming galaxies at z ~ 2.
Using Lyα emission, low-ionization (LIS) interstellar metal absorption
lines, and broad optical emission line components, I measured outflow
velocities and mass outflow rates and explored how these properties
relate to the global properties of their host galaxy. My results show
that these outflow phases are driven by different sources: the cool
(warm) phase is primarily driven by mechanical energy (momentum)
injected into the interstellar medium. In addition, the modest mass
outflow rates of the warm phase suggest that it is negligible relative
to other gaseous phases. On the other hand, the Lyα emission profile
provides indirect constraints on neutral gas kinematics and
distribution. Redshifted single-peaked Lyα profiles are ubiquitous
down-the-barrel of galaxies, while farther out, the profile varies with
LIS outflow velocity and galactic properties, suggesting a clumpy
neutral gas distribution within the circumgalactic medium.This work
provides a glimpse into the complex multi-phase nature of gas cycling
around star-forming galaxies at z ~ 2.
</div><div dir="auto"><br><br></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, May 9, 2024 at 9:50 PM Pooyan Goodarzi <<a href="mailto:pooyan.goodarzi@email.ucr.edu">pooyan.goodarzi@email.ucr.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div>Hi Physics and Astronomy students,</div><div dir="auto"><br></div><div dir="auto"> We will have our next Physics and Astronomy Student Seminar <b>tomorrow</b> at <b>1 PM</b> in the <b>Conference Room</b> (PHYS 3051). In this talk Drew will talk about his PhD research in astronomy. He will be defending his thesis soon and it is appropriated if you can attend this talk to give him comments on his presentation/work. </div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><b>Andrew Weldon</b>, <b>PhD Candidate</b></div><div dir="auto"><b>Friday, 1:00 pm, Conference Room (PHYS 3051)</b> </div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">The Properties of Gas Flows and their Connection to z ~ 2 Star-forming Galaxies
Abstract:
The physical processes that govern the evolution of galaxies are dictated by the cycling of gas into and out of galaxies. The incidence rate and effects of these gas flows are expected to be common and pronounced at redshifts of z ~ 2, the peak of star-formation rate and quasar activity in the history of the Universe. However, there are few direct observational constraints on the properties of outflows in individual galaxies during this epoch. Here, I combine rest-UV and rest-optical spectroscopy to characterize the cool, low-ionized and warm, ionized gas outflow phases from star-forming galaxies at z ~ 2. Using Lyα emission, low-ionization (LIS) interstellar metal absorption lines, and broad optical emission line components, I measured outflow velocities and mass outflow rates and explored how these properties relate to the global properties of their host galaxy. My results show that these outflow phases are driven by different sources: the cool (warm) phase is primarily driven by mechanical energy (momentum) injected into the interstellar medium. In addition, the modest mass outflow rates of the warm phase suggest that it is negligible relative to other gaseous phases. On the other hand, the Lyα emission profile provides indirect constraints on neutral gas kinematics and distribution. Redshifted single-peaked Lyα profiles are ubiquitous down-the-barrel of galaxies, while farther out, the profile varies with LIS outflow velocity and galactic properties, suggesting a clumpy neutral gas distribution within the circumgalactic medium.This work provides a glimpse into the complex multi-phase nature of gas cycling around star-forming galaxies at z ~ 2.
</div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">Best, </div><div dir="auto">Pooyan
</div><br></div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Feb 23, 2024 at 13:52 Ming-Feng Ho <<a href="mailto:mingfeng.ho@email.ucr.edu" target="_blank">mingfeng.ho@email.ucr.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Hello Physics and Astronomy students,<br><br>A group of us are in the process of organizing a weekly seminar series (known as PASS in the past) and would love to invite all UCR Physics and Astronomy graduate students and postdocs to join us. It’s a fantastic opportunity for you to share your research, learn from your peers, and practice your presentation skills in a stress-free environment. Everyone is welcome, both to attend and to sign up as speakers.<br><br>We're in the process of scheduling these seminars at a time that works best for most. We'd greatly appreciate your help in determining this by<span> </span><b>filling out the<span> </span><a href="https://www.when2meet.com/?23833033-4nNwu" target="_blank">when2meet</a></b>.<span> </span><b>We're looking to kick things off next week, so keep that in mind when you're filling it out.<br></b><br><b>If you’re interested in sharing your work as a speaker, please feel free to add your name to the spreadsheet [<a href="https://docs.google.com/spreadsheets/d/15jECocCmSQIZSNxcJ7fcWOEQvixorkXlkUKTVN3AAVk/edit?usp=sharing" target="_blank">Google Sheet</a>].<br></b><br>We’re looking forward to creating a dynamic and engaging series with your involvement!<br><br>Best,<div>Ming-Feng</div><div>Physics and Astronomy Student Seminar (PASS)<br></div><div><br></div><div>---</div><div>Ming-Feng Ho</div><div>PhD Candidate</div><div>Physics and Astronomy</div><div>University of California, Riverside</div><div><a href="http://jibancat.github.io" target="_blank">jibancat.github.io</a><br></div><div><br></div><div><br></div><br></div>
_______________________________________________<br>
Physics-grads-open mailing list<br>
<a href="mailto:Physics-grads-open@lists.ucr.edu" target="_blank">Physics-grads-open@lists.ucr.edu</a><br>
<a href="https://lists.ucr.edu/mailman/listinfo/physics-grads-open" rel="noreferrer" target="_blank">https://lists.ucr.edu/mailman/listinfo/physics-grads-open</a><br>
</blockquote></div></div>
</blockquote></div>