Olin Wilson Legacy Survey (OWLS) – APO Symposium 2021

2021 APO Science Symposium

https://youtu.be/4GpVpZxav3U?si=RK9XfybF_4q0Kuoc

Transcript

1. Olin Wilson Legacy Survey (OWLS) Suzanne Hawley Leslie Hebb Brett Morris
2. Planet-hosting stars are multiplying
4. Planet-hosting stars can be magnetically active
5. Left: The solar photosphere, observed in the light of the λ 4300 CH G band on 2003 November 2. Active region AR10486 is apparent at center. Right: The solar chromosphere in the same location and time, observed in CaII H (images courtesy Dutch Open Telescope). Hall (2008) CH G band (4300 Å) Ca H line (3968.47 Å)
6. Magnetic activity affects observations of exoplanet transits
7. Starspots of HAT-P-11 Davenport (2015) Morris+ (2017a)
8. Starspots of HAT-P-11 Morris+ (2017b) Activity maximum Activity minimum
9. APO/ARCES is ideal for long-term spectroscopic monitoring of active stars
10. APO/ARCES Spectra
11. OWLS Sample • Mostly bright, (F)GKM stars • Mostly planet-hosts ◦ From planet searches such as: HAT, WASP, Kepler, K2, TESS • Also from legacy S-index target lists ◦ From Olin Wilson and collaborators: Duncan+ (1991), Baliunas+ (1995) • Good overlap with historical spectroscopic surveys ◦ Well-represented in archives of: Mt Wilson, HARPS, Keck samples
12. 1. Measure Ca II H & K emission for ~250 stars every ~1-2 years for as long as possible 2. Measure spectroscopic temperatures and metallicities 3. Publish the S indices in real time 4. Use legacy observations where possible (Mt Wilson, HARPS, Keck) to extend time baseline OWLS will:
13. OWLS’ first year by the numbers 23 half nights 180 target stars observed 200 high resolution spectra 4% uncertainty in the S-index 71% mean Moon illumination
14. Observed Unobserved
16. OWLS (in prep) Sun
17. OWLS (in prep) More Active Less active Sun
18. Comparison with Baliunas+ (1995) OWLS
19. Comparison with Baliunas+ (1995) OWLS
20. Comparison with Baliunas+ (1995) OWLS
21. Case Study: 55 Cnc • Slowly rotating K dwarf host star to five planets (39 d) • Planet e is a transiting super-Earth with a density consistent with rock (6.6 g/cm3) • Phase curve of planet cannot be explained strictly by reflection from the planet’s surface • Is stellar magnetic activity to blame? Morris+ (2021) Raw Detrend
22. Case Study: 55 Cnc Activity maximum Activity minimum OWLS Keck/HIRES (In prep) OWLS observations confirm CHEOPS observations occurred near activity maximum Activity maximum
23. Real-time S-indices for all targets: https:/ /owls.readthedocs.io/