Sabrina Marbut Appel

About Me

I am a sixth year graduate student at Rutgers University. I work with Prof. Blakesley Burkhart on understanding and developing analytic models of star formation. My work is focused on comparing simulations of star-forming regions to analytic models of star formation and includes analyzing existing simulation data, running new simulations, and working on code development. You can read more about my research under the research tab or take a look at my CV here.

In addition to my research, I am dedicated to making the field of astronomy a welcoming and supportive community. I am the Past President of the Rutgers Minorities in Physics and Astronomy (MiPA) group at Rutgers, I have served as a TA for multiple undergraduate courses, and have mentored an undergraduate researcher. You can read about my service and outreach work here and about my current and previous teaching and mentoring work here.

I grew up in Salem, Oregon and recieved an International Baccalaureate (IB) diploma from South Salem High School in 2013. I graduated with a B.A. in Physics from Reed College in May 2017 where I also took extensive coursework in English literature and danced as often as I could. I grew up around horses and I love the mountains! I have been dancing (including ballet and Irish dance) for most of my life. In my free time, I love to play the flute, bake, and knit, and I am a voracious reader, especially of science fiction and fantasy.

You can email me at appel at physics.rutgers.edu. If for some reason that is unsuccessful, you can also reach me at sabrina.m.appel at gmail.com.

https://orcid.org/0000-0002-6593-3800

• GitHub

Research

Modeling Star Formation

My current research is focused on understanding star formation and how it is influenced by various physical processes. In particular, my work compares simulations of star-forming regions to analytic models of star formation. I am especially interested in the impact of different stellar feedback processes, such as protostellar outflows. My work includes analyzing existing simulation data, running new simulations, and code development for star formation simulations.

The following are a series of projection plots from the simulations used in our 2022 paper (Appel et al. 2022).

Movies of some of these simulations, as well as new versions of the simulations, can be found here.

Protostellar Jets in Torch

Over the last few years, I have developed a new module for implementing protostellar jets in Torch. Torch is a numerical framework that is optimized for simulating the formation of star clusters from the initial collapse of dense gas through gas expulsion and late stage cluster evolution (Wall et al.2019, 2020). Previous work with Torch has included various modes of stellar feedback, but not protostellar jets (e.g.,Cournoyer-Cloutier et al. 2023). By developing a new module to include protostellar jets, I can use Torch to explore the role of protostellar jets in star cluster formation and evolution.

Publications

† - indicates an undergraduate student mentee

Polak, B., Mac Low, M.-M., Klessen, R. S., Teh, J. W., Cournoyer-Cloutier, C., Andersson, E. P., Appel, S. M., Tran, A., Lewis, S. C., Wilhelm, M. J. C., Portegies Zwart, S., Glover, S. C. O., Wang, L., McMillan, S. L. W., "Massive Star Cluster Formation I. High Star Formation Efficiency While Resolving Feedback of Individual Stars", 2023, arXiv e-prints, arXiv:2312.06509, doi: 10.48550/arXiv.2312.06509

† Kiihne, A., Appel, S. M., Burkhart, B., Semenov, V. A., Federrath, C.,"Fitting Probability Distribution Functions in Turbulent Star-Forming Molecular Clouds", 2023, arXiv e-prints, arXiv:2305.11218, doi: 10.48550/arXiv.2305.11218

Appel, S. M., Burkhart, B., Semenov, V. A., Federrath, C., Rosen, A. L., Tan, J. C., "What Sets the Star Formation Rate of Molecular Clouds? The Density Distribution as a Fingerprint of Compression and Expansion Rates" 2023, ApJ, 954, 93, doi: 10.3847/1538-4357/ace897

Cournoyer-Cloutier, C., Sills, A., Harris, W. E., Appel, S. M., Lewis, S. C., Polak, B., Tran, A., Wilhelm, M. J. C., Mac Low, M.-M., McMillan, S. L. W., Zwart, S. P., "Early evolution and three-dimensional structure of embedded star clusters", 2023, MNRAS, 521, 1338, doi: 10.1093/mnras/stad568

Appel, S. M., Burkhart, B., Semenov, V. A., Federrath, C., Rosen, A. L., "The Effects of Magnetic Fields and Outflow Feedback on the Shape and Evolution of the Density Probability Distribution Function in Turbulent Star-forming Clouds", 2022, ApJ, 927, 75, doi: 10.3847/1538-4357/ac4be3

B. Burkhart, S. Appel, S. Bialy, J. Cho, A. J. Christensen, D. Collins, C. Federrath, D. Fielding, D. Finkbeiner, A. S. Hill, J. C. Ibanez-Mejia, M. R. Krumholz, A. Lazarian, M. Li, P. Mocz, M.-M. Mac Low, J. Naiman, S. K. N. Portillo, B. Shane, Z. Slepian, Y. Yuan, “The Catalogue for Astrophysical Turbulence Simulations (CATS)”, 2020, ApJ, 905, 14,

Service & Outreach

I am currently the Past President (and was previously the Graduate Chair and then President) of the Rutgers Minorities in Physics and Astronomy (MiPA) group. MiPA is dedicated to furthering the interests of and developing a sense of community among members of the Rutgers Physics and Astronomy department who are underrepresented or historically marginalized in Physics and Astronomy. As a leader of MiPA, I helped to draft and implement a Charter and Code of Conduct for MiPA. I also founded our Equity and Inclusion Journal Club. Over my time with MiPA, I have led or helped organize various events and initiatives.

For more about my service and outreach roles, please take a look at my CV.

Teaching & Mentoring

I believe teaching and mentoring are incredibly important and I find working with students to be deeply rewarding. I have served as a TA for several undergraduate courses of various levels. Most recently, in the fall of 2022, I was a TA for an undergraduate Computational Astrophysics course where I helped juniors and seniors progress from the basics of coding in python to running astrophysical simulations.

In addition, I mentored an undergraduate student (recently graduated!!), Avery Kiihne, on a research project investigating fitting methods for simulated column density PDFs. You can find their first paper here! For more about my previous teaching and tutoring experiences, please take a look at my CV.

CV

Click here to take a look at my CV. I will do my best to update it regularly.

This is a 3D volume rendering using yt of a protostellar jet in Torch. Over the past few years, I have developed a new module for implementing protostellar jets in the numerical framework Torch!

Contact

• GitHub

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