ABSTRACT
We present the stellar obliquity measurement of TOI-880 c (TOI-880.01) using Rossiter-McLaughlin (RM) observations obtained with the Keck Planet Finder (KPF). TOI-880 is a compact multi-transiting system with 3 transiting planets. Our independent analysis revealed that the host star is a K-type star. Planet b (TOI-880.02) has a radius of 2.23 ± 0.10R⊕ and an orbital period of 2.6 days; planet c (TOI-880.01) is a Neptune-sized planet with 4.96 ± 0.20R⊕ in a 6.4 day period; and planet d (TOI- 880.03) has a radius of 3.32 ± 0.20R⊕ and a period of 14.3 days. The RM effect of TOI-880 c revealed a sky-projected obliquity of |λ⋆| = 16.6 +5.2 −6.0 ◦ . This indicates that TOI-880 c is in a prograde, likely aligned orbit. The orbital inclinations of the 3 planets are all close to edge-on, suggesting that the entire system is nearly coplanar. No notable excess absorption in the H-alpha line has been observed, suggesting the absence of detectable atmospheric loss.
BIO
Elina is a second-year PhD student at the Institute for Astronomy, University of Hawaii at Mānoa. She earned her BSc in Astronomy from the University of Michigan-Ann Arbor, and her MSc in Astrophysics from University College London. Her research focuses on brown dwarfs and exoplanets. She has worked on characterizing low-mass brown dwarfs and investigating the obliquity of young planetary systems.
Host: Shuo Zhang
