Exploring the process of accretion through the analysis of accreting white dwarfs, focusing on the comprehensive light curves obtained from NASA’s TESS mission.

Research Proposal for the Laidlaw Research and Leadership Scholarship, Louis Peters

Exploring the process of accretion through the analysis of accreting white dwarfs, focusing on the comprehensive light curves obtained from NASA’s TESS mission.

Throughout this experiment, the scope of my research shall change as I understand more and more about accreting white dwarfs. Consequently, I have ensured that the objectives outlined in the succeeding are created from a SMART perspective, in order to employ this opportunity to the fullest extent.

For the first week, I shall build on my current programming abilities and construct the necessary toolbox to understand the data from TESS and in addition to this, further study Fourier transforms beyond the syllabus of my degree. The combination of these skills will enable me to go into great depth in this research project.

I subsequently plan to study the current models of accretion and look at existing reports of accreting white dwarfs as I endeavour to understand as much of what is known at present. I will execute this by looking at a subsample of the 400 light curves and through investigating those, I shall construct a mental database of how different white dwarfs behave subject to different conditions, as well as which methods work to support these binary systems. This will be completed over the next two weeks of the project and the degree of success will be measured by my ability to determine the outstanding features of a sample of random light curves within the TESS data.

As I continue to interpret and comprehend these methods, I will progressively decrease my subsample, continuously delving into further detail. Eventually, I aim to have narrowed it down to either one specific binary system – such as TW Pictoris in Dr. Scaringi’s letter [1] – or alternatively, one specific type of binary system which displays a particular property. This selection process will occur at the end of the first three weeks of the project, allowing the subsequent three weeks to be used in accordance with the research path that I proceed with.

If I investigate a type of binary system, I intend to discern how they compare to our current models: are the current models still accurate taking into consideration the precision of TESS’ data? Does the new data allow current methods to be obviously amended? Am I able to propose my own ideas as to what is happening in these systems?

If I investigate an individual system, I will have selected it having understood how to recognise unfamiliar patterns in light curves and therefore will pick a light curve that appears to exhibit ‘strange’ behaviour. In accordance, I will meticulously study this object in an attempt to postulate what is happening in that specific system.

Regardless of the research path taken in this project, I hope to contribute to our perception of accretion: whether that is our understanding of the behaviour of a particular accreting white dwarf, our understanding of the different mechanisms governing accretion (e.g., magnetic gating) and/or what contributes to the characteristics of different accretion disks. Ultimately, I will produce a report at the end of the six weeks detailing the outcomes of my research and the corresponding implications.

As this research primarily involves the analysis of big data, if the project is to be moved online due to COVID, there are no issues associated with executing the project as expected: all communication can be completed via emails and Zoom/Microsoft Teams calls. My computer has sufficient memory to run the programs necessary to illustrate TESS data.

[1] - S. Scaringi: an accreting white dwarf displaying fast transitional mode switching

Lay Summary

This project intends to understand more about the mechanisms governing certain stars in our Universe. In particular, the stars I will be investigating are at the end of their life – several billions of years old. They are relatively small – around the size of the Earth - and extremely dense – one teaspoon of this star would weigh similar to several cars.

Thanks to unprecedented data available from a NASA satellite, we now have a phenomenal opportunity to examine these stars to a level of precision that has never been possible before: data collected every two minutes for at least one month, for over 400 different star systems. That’s at least 21,600 measurements per system.

​​​​​​​This data provides the opportunity to determine different features of these stars to a high degree of accuracy, ultimately contributing to our understanding of astronomical processes of which we have little apprehension.

Please sign in

If you are a registered user on Laidlaw Scholars Network, please sign in