Research
My main research interest is on the architectures of exoplanet systems. I have been involved in the discovery and characterization of a number exoplanet systems, like a trio of gas giants on short period orbits (TOI-1820, TOI-2025, and TOI-2158) or the discovery of a hot super Neptune right in the Neptunian desert (TOI-1288) shown in the plot below.
I find it especially interesting to learn about the so-called obliquities of these systems. The obliquity is the angle between the stellar rotation axis and the orbital axis of the planet. This quantity can tell us something about the planets' formation and migration history. We can measure the obliquity through the so-called Rossiter-McLaughlin (RM) effect by, for instance, looking at the distortion of the stellar spectral lines during a planetary transit. This distortion traces the path of the transiting planet as it crosses the rotating stellar disk, as shown in the left plot in the video below. The overall effect is a change in the radial velocity (RV) of the star, which is shown to the right. By gauging the morphology of this curve, we can deduce the projected obliquity of the system. For more details on the RM effect check out our paper on the HD 332231 system.
I also have a strong interest in asteroseismology, the study of stellar oscillations. These oscillations can be used to determine the stellar properties with high precision. For instance, I have been involved in a seismic study on one of the first (suspected) planet-hosting stars, γ Cephei A.
Software
I really enjoy coding and making small publicly available software packages with decent documentation. Listed below are some of my better ones:
- coPsi can derive the rotation period of a star and properly deduce the obliquity
- obscurae is a more concise version of
tracitto model the planetary shadow - FIESpipe used to extract, among other things, radial velocities from FIES data
Thesis
My thesis "Starchitectures" can be found here.
Publications
I've (co-)authored several peer reviewed papers as
First author
- Knudstrup, et al. 2024, A&A, 690, A379
- Knudstrup, et al. 2023, A&A, 675, A197
- Knudstrup, et al. 2023, MNRAS, 5129, 5637
- Knudstrup, et al. 2023, A&A, 671, A164
- Knudstrup, et al. 2022, A&A, 667, A22
- Knudstrup & Albrecht 2022, A&A, 660, A99
- Knudstrup, et al. 2020, MNRAS, 499, 1312
Second author
- Addison, Knudstrup, et al. 2021, AJ, 162, 292
- Lund, Knudstrup, et al. 2019, AJ, 158, 248
Third author
- Seidel, Prinoth, Knudstrup, et al. 2023, A&A, 678, A150
- Christensen-Dalsgaard, Gough, & Knudstrup 2018, MNRAS, 477, 3845
A full library of papers, where I've contributed can be found on the NASA ADS.