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Planet Formation in Evolved Binary Stars Nader Haghighipour (Ifa,Hawaii) Tobias Müller (Inst

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Planet Formation in Evolved Binary Stars Nader Haghighipour (Ifa,Hawaii) Tobias Müller (Inst Planet Formation in Evolved Binary Stars Nader Haghighipour (IfA,Hawaii) Tobias Müller (Inst. Astron. & Astrophys., Tübingen) Billy Quarles (NASA Ames) http://www.boulder.swri.edu/~terrell/dtart.htm α Centauri Kepler 47 Observations imply planets in binaries Circumbinary Disk Circumprimary Disk GG Tau (a = 35 AU) HD 141569 Mdisk = 0.2 Solar-mass separation ~950 AU Krist et al. 2005 Clampin et al. 2003 Slightly more than 10% of Extrasolar Planets are in Binary Star Systems http://www.univie.ac.at/adg/schwarz/binary.html (Haghighipour 2006) S t a r S t a r S t a r S t a r HD142 (GJ 9002) HD3651 HD9826 (UpsilonA n d ) HD13445 (GJ 86) HD19994 HD22049 (EpsilonE r i ) HD27442 HD40979 HD41004 HD75732 (55 Cnc) HD80606 HD89744 HD114762 HD 117176 (70 Vir) HD120136 (TauB o o ) HD121504 HD137759 HD143761 (RhoC r b ) HD178911 HD186472 (16 Cyg) HD190360 (GJ 777 A) HD192263 HD195019 HD213240 HD217107 HD219449 HD219542 HD222404 (GammaC e p h e i ) HD178911 PSR B1257-20 PSR B1620-26 γ Cephei : Separation ~ 20 AU 1.67 Jupiter-Mass Planet @ 2.1 AU GL 86 : Separation ~ 28 AU 4 Jupiter-Mass Planet @ 0.11 AU HD41004, HD 196885, HD 176051, α Centauri (?) (23 AU) (23 AU) (21 AU) (23.5 AU) OGLE-2013-BLG-0341 (15 AU) Planetary Dynamics in Binary Stars Deprit and Rom (1970) Heppenheimer (1974, 1978) Ziglin (1975) Harrington (1975, 1977) Drobyshevski (1978), Diakov and Reznikov (1980), Black (1982) Pendleton (1983) Whitmire et al. (1998) Dvorak (1984, 1986, 1988, 1989, 1991) Benest (1988, 1989, 1993, 1996, 1998) Observations imply planets can form in binary star system 10 AU Core of star forming region L1551 contains two disks separated by ~ 45 AU. 45 AU Each disk is ~10 AU wide and has a mass of 0.05 M¤ 10 AU (Bieging & Cohen 1985, Rodriguez et al. 1998) Observations imply planets can form in binary star system (Boss 1998) “Probable third body variation of 25 m/s amplitude, 2.7 years period, superposed on a large velocity gradient. Status of astrometric perturbations is unknown” Cambpell, Walker & Yang [ApJ, 331, 902 (1988)] γ Cephei: First planetary system in a close binary (binary semimajor axis = 20 AU) Hatzes et al (2003) Orbital solution for the planet (line) and the residual Phased residual RV measurements from CFHT and velocity measurements of the four data sets after McDonald phase IIII compared to the planet orbital subtracting the contribution due to the binary solution (line). companion (points). Jovian-type planet = 1.67 MJ Semimajor axis = 2.1 AU Eccentricity = 0.12 0.44 solar-mass γ Cephei (M star) Primary Star 1.6 MSun K 1 IV-III giant 1.67 Jupiter-mass http://mcdonaldobservatory.org/news/releases/2002/1009.html A stellar companion can truncate the disk by 50-90% 2 2 aStability = a(0.464 − 0.38µ − 0.631e + 0.586µ e + 0.15e − 0.198µ e ) Rabl & Dvorak (1988), Holman & Wiegert (1999 ) (Artymowicz & Lubow, 1994) Slightly more than 10% of Extrasolar Planets are in Binary Star Systems http://www.univie.ac.at/adg/schwarz/binary.html (Haghighipour 2006) S t a r S t a r S t a r S t a r HD142 (GJ 9002) HD3651 HD9826 (UpsilonA n d ) HD13445 (GJ 86) HD19994 HD22049 (EpsilonE r i ) HD27442 HD40979 HD41004 HD75732 (55 Cnc) HD80606 HD89744 HD114762 HD 117176 (70 Vir) HD120136 (TauB o o ) HD121504 HD137759 HD143761 (RhoC r b ) HD178911 HD186472 (16 Cyg) HD190360 (GJ 777 A) HD192263 HD195019 HD213240 HD217107 HD219449 HD219542 HD222404 (GammaC e p h e i ) HD178911 PSR B1257-20 PSR B1620-26 γ Cephei : Separation ~ 20 AU 1.67 Jupiter-Mass Planet @ 2.1 AU GL 86 : Separation ~ 28 AU 4 Jupiter-Mass Planet @ 0.11 AU HD41004, HD 196885, HD 176051, α Centauri (?) (23 AU) (23 AU) (21 AU) (23.5 AU) Effect of Stellar Companion on the Dynamics of Planetesimals - Increasing eccentricity -Increasing mutual collisions -Increasing the possibility of coalescence/ejection Thiebault et al (2004) Stellar companion may increase Thebault et al (2004) the eccentricities of planetesimals -Increasing relative velocities -Scattering -Shattering Impacting bodies: 2.5 km – 5 km Thebault et al (2006) Planetesimal Accretion Planetesimals in the outer region of a precessing gaseous disk have lower relative velocities. The low velocity region approaches close distances as the size of a planetesimal increases. Beauge, Leiva, Haghighipour, Correa Otto (2010) (Müller & Kley 2012) Dust Growth in Circumprimary disks An eccentric secondary inhibits dust grains to grow larger than a few mm in size. Zsom et al (2011) Slightly more than 10% of Extrasolar Planets are in Binary Star Systems http://www.univie.ac.at/adg/schwarz/binary.html (Haghighipour 2006) S t a r S t a r S t a r S t a r HD142 (GJ 9002) HD3651 HD9826 (UpsilonA n d ) HD13445 (GJ 86) HD19994 HD22049 (EpsilonE r i ) HD27442 HD40979 HD41004 HD75732 (55 Cnc) HD80606 HD89744 HD114762 HD 117176 (70 Vir) HD120136 (TauB o o ) HD121504 HD137759 HD143761 (RhoC r b ) HD178911 HD186472 (16 Cyg) HD190360 (GJ 777 A) HD192263 HD195019 HD213240 HD217107 HD219449 HD219542 HD222404 (GammaC e p h e i ) HD178911 PSR B1257-20 PSR B1620-26 γ Cephei : Separation ~ 20 AU 1.67 Jupiter-Mass Planet @ 2.1 AU GL 86 : Separation ~ 28 AU 4 Jupiter-Mass Planet @ 0.11 AU HD41004, HD 196885, HD 176051, α Centauri (?) (23 AU) (23 AU) (21 AU) (23.5 AU) 0.44 solar-mass γ Cephei (M star) Primary Star 1.6 MSun K 1V–III giant 1.67 Jupiter-mass http://mcdonaldobservatory.org/news/releases/2002/1009.html Binary Semimajor axis : 27.8 AU GJ 86 Eccentricity : 0.1 (Farihi et al 2013) Planet Mass : 4.4 – 4.7 MJup Semimajor axis : 0.11 AU Primary SpT : K0 V Mass : 0.8 MSun Age : 2.5 Gyr Secondary (WD 0208-510) SpT : DQ6 Mass : 0.59 MSun Radius : 0.01245 RSun Cooling Age : 1.25 Gyr Secondary MS Progenitor SpT : A5 V Mass : 1.9 MSun Lifetime : 1.4 Gyr Hurley et al (2000) On the GB (Kudritzki & Reimers 1978) dM −13 2 L R = 4 ×10 η MSun dt M On the AGB (Vassiliadis & Wood 1993) dM log = −11.4 + 0.0125[P0 −100 max(M − 2.5 , 0)] dt log P0 = min(3.3, − 2.07− 0.9 log M +1.94 log R) γ Cephei M0=1.65 Msun , Z = 0.003 SSE code (J. Hurley) M / LR Haghighipour, Mueller, Quarles (in prep.) t = 0 t = 1100 Myr GJ 86 Analog @ primary MA = 0.8 Msun MB = 1.9 Msun aAB = 14.5 AU GJ 86 Analog @ secondary MA = 0.8 Msun MB = 1.9 Msun aAB = 14.5 AU γ Cephei Analog (evolved primary) -Planet(s) form around MS primary -Primary evolution à variations in (a,e)Sec K 1V sub-giant -Strong variations in eSec à planet-secondary interaction -Ejection & Scattering of planets to new orbits GJ 86 analog (evolved secondary) -Unperturbed disk/planets around primary -planet(s) form around the primary -planet-planet interaction à Ejection & scattering into new orbits -Expanding disk/planetary orbits @ Second. -Planet-planet scattering à Ejection -Very low probability of capture @ primary -Second generation formation may be possible .
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