Graduate student, Caltech
B.S., M.S. in Astrophysics
Natsuko Yamaguchi
ABOUT ME
Understanding how stars interact in binaries
Hi! My name is Natsuko and I'm a PhD candidate at the California Institute of Technology. My advisor is Kareem El-Badry and my thesis work is focused on constraining the physics of mass transfer processes in binary systems. I primarily do observational work, studying the population of post-interaction binaries, though I also often work with theorists to model their evolution.
I was born in Japan, though I spent most of my life abroad. I've lived in China, Singapore, Thailand, Cambodia, and moved to the U.S. for undergrad. I got my B.S. in Astrophysics at UCLA where I worked with Steven Furlanetto, doing work in theoretical cosmology studying metal enrichment in the high-z universe. Prior to this, I was also part of a neurophysics group lead by Katsushi Arisaka.
Research Focus
All of my current work revolve around multiple star systems. I'm particularly interested in the close binaries where mass transfer occurs between the components as one evolves off the main sequence and expands.
Binary interactions are crucial to the formation of many important and exotic astrophysical systems, but there are many aspects of it that remain poorly understood.
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(The image above is of a resolved hierarchical triple, composed of a WD self-lensing binary and an outer luminous component - check out my paper on it! This was captured with PHARO at the Palomar Observatory.)
White dwarfs play an important role in my work because they are the end products of most stars, meaning that they are what's left behind in binaries after interactions have taken place. We can learn a lot about the evolutionary history of a population by looking at the leftovers.
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(An image of Sirius taken by the HST, the little dot on the lower left is the white dwarf, Sirius B.
Copyright: NASA, ESA, H. Bond (STScI), and M. Barstow (University of Leicester))
In my research, I deal with a range of tools and datasets. Most commonly, I work with orbital solutions provided by Gaia DR3 to identify and study systems hosting compact objects, optical spectra to obtain radial velocities and abundances, and light curves to look for self-lensing systems.
My primary coding language is Python, though I have a little bit of experience with Fortran, MATLAB, and C++.