Mapping the Realm of Hot Jupiters Bunei Sato

Mapping the Realm of Hot Jupiters Bun’ei Sato, Shigeru Ida（Titech）, Eri Toyota（Kobe Univ. ）, Masashi Omiya（Tokai Univ. ）, Debra Fischer（SFSU）, Greg Laughlin（UC Santa Cruz）, Paul Butler（Carnegie Inst. of Washington）, Geoff Marcy（UC Berkeley）

Mapping the Realm of Hot Jupiters l Doppler search for Hot Jupiters with Subaru/HDS, Keck, Magellan（N 2 K consortium） l l l Hunting “transiting” planets Since 2004, 14 planets were discovered from N 2 K 2 transiting planets （HD 149026 b, HD 17156 b） from Subaru !! Many planet-candidates are waiting for follow-up Subaru intensive program l l S 06 A（10 nights）, S 06 B（10 nights） Determine orbital parameters of planet-candidates making use of long time-baseline

Hot Jupiters l Giant planets in short-period orbits l l l High-probability transit candidates l l l information about planet itself （radius, internal structure, atmosphere, etc. ） ex) HD 149026 b has an extraordinary huge solid core (Sato et al. 2005) Tracers of multi-planet systems l l l P＜ 14 d: ~70 HJ so far (30 are from transit surveys) Frequency ~ 1% resonant configuration orbital evolution of planetary systems Test case of planet formation theory l migration, tidal circularization, , ,

N 2 K Consortium l. Keck（USA）、Magellan（Chile）、 Subaru（Japan） l. Search for Hot Jupiters around next 2000 solar-type stars l. Aiming to detect 60 Hot Jupiters and 5 -6 transiting planets l. Precise Doppler measurement using Iodine absorption cell l. Current precision with HDS ~4 m/s （short-term） ~10 m/s （long-term）

Strategy l. Database of 14, 000 stars ・ V＜ 10. 5, d＜ 110 pc, FGK V, IV P=0. 03 x 10^2[Fe/H] ・ metalliicty, activity, binary, , , l. High priority to metal-rich stars Detection probability from Monte Carlo Simulation （0. 5 MJ） l３＋１ nights observation ・Identify candidates in 3 consecutive nights 　　・RMS＞ 20 m/s → follow-up 　　・RMS＜ 20 m/s → drop ・Confirm candidates after 1 more night in 1 month later

Status: Keck & Magellan Keck 3 nights/yr 600 stars 12 planets (6 hot Jupiters) 30 more planet candidates Magellan 3 -4 nights/yr 380 stars 20 planet candidates

Status: Subaru • S 04 A（4 nights） • S 04 B（4 nights） • S 05 B（5 nights） • S 06 A（10 nights） 6 （Jun. ）+4 （Jul. ） • S 06 B（10 nights） 10 （Dec. ） • S 08 A（1. 5 nights） find planet candidates confirm orbital parameters （and find new planet candidates） follow-up planet candidates 635 stars >3 times: 512 stars <2 times: 123 stars

Metallicity: All N 2 K Targets 1291 stars 88 planets expected Nobs = 188 P=0. 03 x 10^2[Fe/H] Fischer et al. in preparation

Metallicity: Subaru Targets 504 stars 30 planets expected Nobs = 188 P=0. 03 x 10^2[Fe/H] Fischer et al. in preparation

RV Variations: Subaru Targets 471 stars 64 stars （20<σRV<200 m/s） -2 published planets -HD 149026, HD 17156 -3 strong planet-candidates at present -15 stars showing intermediate- to long-term trend (planet or SB) -20 possible planet-candidates -Others (active stars etc. )

Planet Candidates from Subaru P~35 d Green: Keck　　Red：Subaru P~500 d P~700 d

Eccentric Short-Period Planet: HD 17156 b HD 17156 （G 0 V, V=8. 2） 　 M 1=1. 2 M , R 1=1. 47 R 　 [Fe/H]=0. 24, Age=5. 7 Gyr Mpsini=3. 1 MJUP P=21. 2 d K 1=275 m/s a=0. 15 AU e=0. 67 Periastron distance q=a（1 -e）=0. 05 AU Green: Keck　　Red：Subaru Mercury Tidal force from the central star Planet evolving to a hot Jupiter? Fischer et al. 2007, Ap. J, 669, 1336 HD 17156 b

Eccentricity Distribution of Exoplanets q=0. 05 AU HD 17156 b circularized

Formation of Hot Jupiter l Orbital Migration l migration due to interaction with disk l small eccentricity l Sling-shot Scenario l gravitational interaction between planets l one planet scattered close to the central star (with large eccentricity) becomes a hot Jupiter due to tidal force from the central star

Aug. 16, 2008　Web release (homepage of Subaru)

Transit Detection in HD 17156 Sep. 9 -10, 2007 (UT)　Amateur in Italy Barbieri et al. 2007, A&A, 476, L 13 Transit depth～ 0. 6％ Rplanet 1. 15± 0. 11 RJUP Two of the two planets found by Subaru are transiting ones !!

Sky Projected Angle between Stellar Spin Axis and Planetary Orbital Axis：λ Stellar spin axis is on YZ-plane Ohta et al. 2005 RM effect λ and Vssin. Is Rossiter-Mc. Laughlin Effect λ=0° λ=30° Gaudi & Winn 2007 λ=60°

Previous Observations λ（°） Mp（MJ） a（AU） e HD 209458 -4. 4± 1. 4 0. 66 0. 0474 0. 015 Winn et al. 2005 HD 189733 -1. 4± 1. 13 0. 0312 0. 001 Winn et al. 2006 HD 147506 1. 2± 13. 4 8. 0 0. 0686 0. 5 Winn et al. 2007 HD 149026 -12± 15 0. 35 0. 0432 0 Wolf et al. 2007 Tr. ES-1 30± 21 0. 76 0. 0394 0 Narita et al. 2007 ｜λ｜=0～ 30° No large misalignment Reference

Photometric and Spectroscopic Observations of HD 17156 11 Nov. 2007 by Osamu Oshima at Kurashiki-shi Orbital Period =21. 2162± 0. 0036 d Planet radius/Stellar radius ＝ 0. 08462 1. 21± 0. 12 RJ Narita et al. PASJ, submitted

RM effect λ=62± 25° ＠OAO/HIDES λ=60° ●岡山、▲すばる、■ケック Narita et al. PASJ, submitted

HD 17156 λ（°） Mp（MJ） a（AU） e Ref. HD 209458 -4. 4± 1. 4 0. 66 0. 047 0. 015 Winn et al. 2005 HD 189733 -1. 4± 1. 13 0. 031 0. 001 Winn et al. 2006 HD 147506 1. 2± 13. 4 8. 0 0. 069 0. 5 Winn et al. 2007 HD 149026 -12± 15 0. 35 0. 043 0 Wolf et al. 2007 Tr. ES-1 30± 21 0. 76 0. 039 0 Narita et al. 2007 HD 17156 62± 25 3. 13 0. 15 0. 67 Narita et al. 2007 First possible candidate with large spin-orbit misalignment

Summary & Future Prospects l 2 planets have been found so far from Subaru l both of them are transiting ones, and they are unique and give big impact on planet formation theory l Metallicity database of all the N 2 K targets will be published soon l Improvement of RV precision of HDS is still required l l ~10 m/s offset between observing runs Continuous observations are necessary to investigate cause of RV variations for 40 more candidates l l Queue-observations are helpful Ex. ) 1 -2 hours x many days