What can we learn by evolving the host star? Eva Villaver Universidad Autónoma de Madrid

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1 What can we learn by evolving the host star? Eva Villaver Universidad Autónoma de Madrid

2 WD POLUTION PLANET STIRRING A LEFT OVER DEBRIS DISK ROTATION 1-3 % FAST RGB ROTATORS PLANET STAR CHEMISTRY LITHIUM RICH STARS 22%A(LI) > 1.5 PLANET METALLICITY RELATION PLANETARY SYSTEM EVOLUTION STELLAR EVOLUTION ASYMMETRIC MASS-LOSS ENERGY DEPOSITION MIGHT LEAD TO ORBITAL EVOLUTION ENGULFMENT SURVIVAL ENVELOPE EJECTION

3 Planet formation

4 The process WD

5 The star

7 Chemistry Maldonado, Villaver & Eiroa (2012); See also Mortier et al. (2013); Zielinski et al. (2010)

8 Planet formation/ STellaR mass Mordasini et al. (2012)

9 Lithium-Rich K Giants 1 [Fe/H] = The Astrophysical Journal Letters, 730:L12 (5pp), 2011 March Kumar, Reddy, & Lambert 3 3 (a) (b) reaction 3 He(3 He, 2p)4 He which lowers the mean molecular (b) weight and the homogenization of the composition within the convective envelope. Eggleton et al. (2008) show that this inversion leads to compulsory mixing and changes to the 2.5 surface abundances of C, N, and O isotopic abundances, i.e., the 12 C/13 C ratio is lowered relative to its value before the bump. Charbonnel & Lagarde (2010) recognize too that mixing occurs as a result of the molecular weight inversion but include 2 the effects of rotationally induced mixing to drive the mixing. This mixing referred to as δµ-mixing by Eggleton et al. (2008) or thermohaline mixing by Charbonnel & Lagarde (2010) is observationally confirmed by measurements of the 12 C/13 C ratio 1.5 in giants along the RGB showing a decrease in the ratio at and above the luminosity of the bump. As p-captures on 12 C create 13 C, the reservoir of primordial and main-sequence synthesized 3 He is depleted. It 1 is this reservoir that is a potential source of 7 Li from the Cameron Fowler (Cameron & Fowler 1971) mechanism [Fe/H] = 0.0 = 0.0 (3 He(4 He, γ )7 Be(e, ν)7 Li) but in order for the 7 Li to[fe/h] enrich the stellar atmosphere it and its progenitor 7 Be must be swept 0.5 quickly to temperatures too cool for proton captures to occur calculations 5000 Eggleton et al. (2008) show that more4500 than about % of the He is destroyed in stars of masses less than about Kumar, Reddy & Lambert 730, L12! 2.ApJ, Stars from our (blue symbols) and Brown et al. (1989) 1.5 M.(2011), ThisFigure destruction seems unlikely to produce lithium be- (green symbols) survey are (panel (a))the along tracks computed by Bertelli 7 with evolutionary cause the mixing is shown too slow for Be and 7 Li to avoid deet al. (2008). Li-rich K giants are shown in panel (b): blue filled circles denote Brown et al. (1989) struction by new protons (Lattanzio et al. 2008). However, the initial Li-rich giants found in this study, green symbols are Li-rich giants from subsurface 3Brown He reservoir is such that only a minor fraction et al. (1989), and magenta symbols are other Li-richofgiants taken from 3 Symbol size indicates amount of Li. The base of the RGB is shown the He needthetoliterature. be converted with moderate efficiency to proas a giant. broken red and red portion each of the tracks represents the location vide an Li-rich It isline anticipated thatonthe lithium produced of the luminosity bump which is predicted be seen for masses M! 2 M. as the star crosses the bump s luminosity mayto be destroyed The thick black lines represent the clump region for He-core burning stars of as the star with convective envelope evolves to the tip of massesits M. the RGB. (A color version of this figure is available in the online journal.) The evidence from Figure 2 is that few of the Li-rich stars are aligned along the run of bump stars in the H-R diagram. RGB base Finite luminosity spread, Li-rich stars concentrated at the clump of the RGB. Cameron-Fowler mechanism 2 above th As pmordial is this the Cam (3 He(4 H the stella quickly Eggleton 80% of 1.5 M. cause th struction subsurfa the 3 He vide an L as the s as the s the RGB The e are align Althoug many Li suggest the bump with the the theor stars. If evolutio the surv stars bec than the the tip o RGB, m the RGB the Cam core flas Since E with M that the in stars the rang He-core

10 Lithium Alexander (1967)! planet engulfment? Adamow et al. (2014)! See also: Anthony-Twarog et al. (2013); Lebzelter et al. (2012); Martell & Shetrone (2013); Adamow et al. (2012)

11 Rapid RGB rotarors 18 (Carlberg et al. 2009; Massarotti 2008) Stellar mass and metallicity for a sample of low-mass Carlberg et al. (2011) rapid rotators 2.2 % of a Fig. 2. Projected rotational velocity, v sini, asafunctionoftemperatureforallofthestarsi our sample. Triangles, squares, andsample X s represent of slow 1300 rotators K-giants (v sin i<10 km s 1 ), rapid rotator (v sin i 10 km s 1 ), and flagged stars (see Section 3), respectively. Arrows indicate upper limit The typical error bar in v sin i is 0.5 km s 1.

12 STellar Rotation García-Segura, Villaver et al. (2014) Need a companion! Soker (1997) de Marco (2009) de Marco et al. (2013)

13 Structural changes on AN AGB STAR Siess & Livio (1999ab) BD accretion by giant stars! Struck et al. (2002, 2004) wind accretion effects on substellar companions (10-50 M J ) by Mira winds.! case Low acretion rates Siess& Livio (1999b)

14 Stellar induced changes in planetary evolution.

15 The planet (s)

Orbital evolution (ȧ ) a M = + M p 2 M + M p

16 Orbital evolution (ȧ ) a M = + M p 2 M + M p M p v [F f + F g ] (ȧ ) a t, (ȧ ) a t = f τ d M env M q(1 + q) ( R a ) 8, Villaver & Livio (2009); Kunimoto et al. (2011); Nordhaus & Spiegel (2013); Mustill & Villaver (2012); Adams & Bloch (2013); Villaver et al. (2014)

17 Orbital evolution on the RGB Mass-loss dominates orbital evolution 3.5 Orbit decays but planet avoids engulfment 3 a, R (AU) Planet enters the stellar envelope time (yr) x 10 9 Villaver & Livio (2009); Villaver et al. (2014)

18 Dependencies Mn 1 Mj 2 Mj 5 Mj 10 Mj 2M η 0.2 af [AU] Planet mass a o [AU] 1M J,η M af [AU] Stellar mass a o [AU] Villaver et al. (2014)

19 Menv = Mstar and Renv = 0 Mstar=constant Kunitomo et al. (2011)

20 When..Is It Important? If we are interested in the overall evolution of a planetary system the most important phase is the AGB. AGB star reaches the largest radius and most of the mass-loss takes RADIUS MASS-LOSS Rgb Agb Rgb 10% Mass Agb 60 % Mass

21 AGB evolution Final location of the innermost surviving planets Mustill & Villaver (2012)

22 Unstability

23 Multiple-planetary Systems So far multiplicity: 22% official Kepler #?

24 WD metal pollution Talks by: J. Debes A. Mustill D. Veras Mustill, Veras & Villaver (2014) Duncan & Lissauer (1998); Debes & Siggurdson (2002); Veras & Mustill (2013); Bonsor et al. (2011); Debes (2012); Frewen & Hansen (2014)

25 Engulfment Mp /Menv Fast decay Binding parameter uncertain Livio & Soker (1988) Mj might survive Villaver & Livio (2007) Nordhaus et al. (2010) Gabi Perez /IAC

Nature KIC 05807616 two Earth-like planets at 0.0060 & 0.0076AU Charpinet et al.

(2012) remnants of one or two Jovian-mass planets that lost extensive mass during

26 Nature KIC two Earth-like planets at & AU Charpinet et al. (2007) Bear & Soker (2012) Passy et al. (2012) remnants of one or two Jovian-mass planets that lost extensive mass during CE phase. Han et al. (2002) Form single sdb stars via merger of two He WDs, planet formation following this event may be possible.

27 Binaries

2. Evolution of the the zero-velocity curves for a planet as the primary (cyan) loses mass. The white regions indicate where the may orbit.

The dashed-tail shows an episode of orbital bouncing, which continues while the curves remain open.

A movie evolution is available at http://www.cfa.harvard.edu/ kkratter/binaryplanets/zvelmovie.mpg.

28 2. Evolution of the the zero-velocity curves for a planet as the primary (cyan) loses mass. The white regions indicate where the may orbit. The bottleneck surrounding the first Lagrange point opens midway through the mass loss phase, allowing the planet to oth components of the binary. The dashed-tail shows an episode of orbital bouncing, which continues while the curves remain open. end of the mass loss phase, the zero-velocity surface has been pinched off, and the planet is trapped around the secondary. A movie evolution is available at kkratter/binaryplanets/zvelmovie.mpg. Kratter & Perets (2012) See also Perets (2010), Veras & Tout (2012), Moekel Verastwo (2012) into the stellar binary this results in oscillations varying&only parameters produces a complex set of Jacobi constant for some surviving test particles. outcomes because the probabilistic fate of a planet de-

29 Planets x 1 12 x 10 3 Source of mass and angular momentum onto the star Modifies orbital parameters of the planet M*(t), R*(t)

30 Summary Evolved stars can offer important insight into: 1- the planet formation process: metallicity, stellar mass dependency 2-Stellar evolution: rotation, Li, 3-Physical process associated to planetary system evolution.

Origin of Li Anomaly in K giants. Planet engulfment scenario plays role? Bharat Kumar Yerra. Lunch Talk, 22nd October 2014

Origin of Li Anomaly in K giants. Planet engulfment scenario plays role? Bharat Kumar Yerra. Lunch Talk, 22nd October 2014 : Planet engulfment scenario plays role? Stellar Abundances & Galactic Evolution Group NAOC, Beijing Lunch Talk, 22nd October 2014 Collaborators: Dr. B. Eswar Reddy (IIAP, Bangalore, India) Dr. David L.