Observation and analysis of the youngest transiting planet candidate

1. Observation and analysis of the youngest transiting planet candidate Stefanie Rätz Research Fellow, ESA, ESTEC, Noordwijk, The Netherlands

2. YETI – Young Exoplanet Transit InitiativeSearch for transiting planets in young open clusters • Main goal: Search for close-in, young planets and Brown Dwarfs with the transit method • Young, open star clusters provide an ideal environment because they have a relatively high number of stars of same age, metallicity and distance • Can give constraints on: • Limits for time scales of planet formation and migration • Effect of age, environment and metallicity on frequency of planets • Evolutionary models of planets and Brown Dwarfs • Additional scientific output: • Constraints on Metallicity, age, distance • Large number of variable stars could be analyzed • Different clusters in a range of 1-200 Myr were selected Neuhäuser et. al. (2011)

3. Transit Observation • we launched an international observing campaign • Strategy: collecting data from 0.6 - 2.6-m telescopes spread worldwide at different longitudes • Aim: Observations 24/7 • three runs per year per cluster in two or three subsequent years: typically one to two weeks long

4. Tenagra II 0.8-m telescope Llano del Hato Observatory 1-m Schmidt telescope Sierra Nevada 1.5-mtelescope Gunma Astronomical Observatory 1.5-m telescope Gettysburg Collage Observatory 0.4-m telescope Jena Astrophysical Institute 0.9/0.6-m telescope Stara Lesna Astronomical Institute 0.6-m telescope Byurakan 1.0 and 2.6 telescopes Xinglong Observatory 90/60 cm Observatorio Cerro Armazones two 5.9’’ telescopes Stony Brook 14““ telescope Swarthmore 0.6-m telescope Calar Alto 2.2-m telescope Nainital State Observatory 1-m telescope Torun 60cmtelescope Rozhen 0.6 and 2-m telescopes Lulin Lulin Observatory 1m Telescope Mauna Kea Univ. of Hawaii 2.2m telescope

5. 1 Myr 3 Myrs 10 Myrs 100 Myrs 30 Myrs 25 Ori cluster(Briceño et al. 2007) • Well defined group of at least 200 low-mass pre-main-sequence stars • Concentrated within ~1° of the early-B star 25 Ori in Orion OB1a • The parallaxes of the Hipparcos stars yield a mean distance of 323 pc • Low mass members follow a well- defined band in the color-magnitude Diagram  isochronal age ~7-10 Myrs • disk lifetime: ~ 5 -10 Myrs, hence 25 Ori cluster at the very age, when planet formation finishes • Most populated cluster in this age range known within 500 pc  excellent laboratory to study the early evolution of sun-like stars, protoplanetary disks, and planet formation

6. Observations • Start ofthemonitoringof 25 Ori: January 2010 • Observationsfromthree different Observatoriesbeginningof2010 • University Observatory Jena: 15 nights • Season 1 (winter 2010/2011): • 2010 Dec. 10 – 17, 2011 Jan. 14 – 24, 2011 Feb. 16 – 28 • Observationsfrom 13 different Observatories • University Observatory Jena: 52 nights • Season 2 (winter2011/2012 ): • 2011 Dec. 05 – 16, 2012 Jan. 09 – 18, 2012 Jan. 31– Feb. 09 • Observationsfrom12 different Observatories • University Observatory Jena: 42 nights • Season 3 (winter2011/2012 ): • 2012 Dec. 04 – 14, 2013 Jan. 08 – 18, 2013 Feb. 10 – 17 • Observationsfrom 7different Observatories • University Observatory Jena: 5nights

7. Duty Cycle: 54.5%

9. First Transit candidate

12. Barnes et al. 2013

13. Observations • Start of the monitoring of 25 Ori: January 2010 • Season 1 (winter 2010/2011): 52 clear nights including 13 transits • Season 2 (winter 2011/2012): 42 clear nights including 11 transits • Season 3 (winter 2012/2013): only 5 observing nights • Follow-up observations on the Observatorio de Sierra Nevada, Spain • 5 transit observations in 2013 Nov-Dec • After each season all transits were combined

16. Barnes et al. 2013: a precessing planet transiting a gravity-darkened star

17. Gravity Darkening Fast rotation  star is oblate (larger radius at the equator than at the poles)  poles have a higher surface gravity, and thus, higher temperature and brightness

19. Outlook

20. Gaps in the observations were interpolated with 3rd order polynomials (continuity of the data points)

21. before

22. see Poster M. Kitze (EP-5)

23. Thank you for your attention !!!