## Hello there! I'm Mason Ng, a graduate student at the MIT Kavli Institute for Astrophysics and Space Research Fourth Year PhD Candidate masonng@mit.edu

I am Wei Chieh Ng (Mason) (personal pronouns: he/him).

I am currently a fourth-year graduate student at MIT's Department of Physics and the Kavli Institute for Astrophysics and Space Research. I mainly work with Professor Deepto Chakrabarty, Dr. Paul Ray, Dr. Ronald Remillard, and Dr. Jack Steiner on X-ray timing and spectroscopic analyses of neutron stars with the NICER data.

This website, like myself, are works in progress. You can learn more about me and my previous endeavors in the other sections of my website.

## CV

This is my CV from prior to September 2018, though lightly edited to reflect my current position. I leave it here for posterity.

## Current Research

My present work focuses on three main areas:
• Spectral Evolution of NGC 300 ULX-1 (characterization with NICER data in conjunction with Swift and XMM-Newton). For some early results, which relied on assumptions that ultimately did not hold up, see the poster I presented at the 20 Years of Chandra Science Symposium.
• Developing a Pipeline for Pulsation Searches on Archival and Incoming NICER Data
• X-ray Polarimetry with IXPE

## Past Research

I previously worked on many facets of astrophysics...

In reverse chronological order,

Investigated the effects of different magnetic field strengths and configurations on the structure of the stellar atmosphere of solar-type stars.

Studied absorber kinematics of 31 OVI absorbers, which exhibited a strong halo mass dependence, where absorbers hosted by L* galaxies have the largest velocity dispersions compared with lower masses and group environments, due to a match between virial temperature and the temperature at which OVI ionization fraction is greatest. Total column densities follow the same behavior, consistent with simulations. Relative absorber--galaxy kinematics of the same sample was studied, though the mass dependence was first normalized out to account for the range of halo masses in the sample. Non-virialized motions due to outflowing gas was observed. Accreting gas signatures were not observed due to multiple line-of-sight structures that were observed, resulting in "kinematic blurring". These results indicate that OVI is not an accurate probe of baryon cycle processes.

There were two projects I carried out:

1) I performed evidence calculations with a trio of codes (CosmoMC, PolyChord, and ModeCode) on several inflationary models, most notable of which is the inflection point inflationary model. Results obtained showed that it is comparable in likelihood to quadratic potentials.

2) I also looked at quantifying the impacts of dark matter on the cosmic microwave background using the 2015 Planck likelihoods, in order to demonstrate the predictive power of dark matter. It was found that dark matter was needed at least at the $10^{100}$ level. While the physical effects of dark matter are well-understood, this quantitative calculation has not been reported in the literature.owave Background.

The results are all summarized in my Senior thesis (US)/Honours thesis (NZ/Aus).

The project involved training a computer to predict image quality from the SkyMapper telescope by considering environmental conditions and telescope configurations. The SkyMapper telescope atop Siding Spring Observatory surveys the entire Southern sky in multiple wavelengths. SkyMapper will inevitably find millions of celestial objects. One result was that the angle of rotation of the CCD camera resulted in visibly lower quality images. Once this was discovered, the SkyMapper team disabled that telescope setting.

Working with Georgie Taylor, we created over 1300 stellar atmosphere models for use in BPASS, the state-of-the-art code incorporating binary stellar systems to predict properties of stellar populations. Results of our work have contributed to the analysis of the recently announced gravitational waves, where it was concluded that similar events are more likely to occur in low-metallicity environments.

I am the Development Chair of the MIT Graduate Student Council External Affairs Board (GSC EAB), and am responsible for general programming of the and the maintaining of the EAB newsletter (see latest here). The GSC EAB is broadly the external arm of the MIT GSC, advocating on behalf of MIT graduate students in issues of concern to the group (e.g., climate change, research funding). We typically liaise with staffers in Congress and the Biden administration through letters and meetings. We have also sent out statements endorsing certain and relevant legislation (see here.)

I also co-lead the PhysGAAP initiative, where we provide application guidance resources to prospective applicants to reduce the barriers for application to the MIT Physics PhD program, and to address the underrpresentation of students from historically excluded communities. We provide a mentorship program, virtual webinars, as well as a Q&A service. More information can be found here.

I am also a part of MIT Astrogazers, a group of MIT astrophysics graduate students, who take out telescopes on clear nights to the public and invites them to marvel at bright celestial targets like the Moon, Saturn, and Jupiter (when they are up!)

## Personal History

I come from New Zealand, though my roots stem from Malaysia, where both my parents are from. I have lived in six cities in four countries, over three continents throughout my life!

## Setting up your personal website

I am not sure if this might be useful, and there are many excellent resources on the internet, but I thought it might be nice to have a quick summary of how I created this website. It serves as a personal record for myself, but I hope this could be useful to someone else who may be daunted (I was!) by the idea of making a website from scratch.

First of all, you do not need to have expert (or even basic) HTML knowledge. If you have had coding experience in any language, you can adapt to the syntax by looking at the code structure in a template and copying it. If you want to perform more elaborate operations, then going through some tutorials (Codecademy) will be instructive.

## Resources

Here are some resources that you should check out, especially if you are thinking about undertaking graduate studies in astrophysics/physics!

## Contact

Please feel free to contact me here or through my email masonng@mit.edu if you have any questions!