Planetary Systems of post-common envelope binaries Stefan Dreizler Institut für Astrophysik Göttingen PLATO Meeting Berlin Meeting PLATO Based on Two planets– orbiting the recently formed post-common envelope binary NN Serpentis A&A 521, L60 (2010) K. Beuermann1, F. V. Hessman1 , S. Dreizler1, T. R. Marsh2, S.G. Parsons2, D.E. Winget3, G. F. Miller3, M. R. Schreiber4, W. Kley5, V. S. Dhillon6, S. P. Littlefair6, C.M. Copperwheat2, J. J. Hermes3 The giant planet orbiting the cataclysmic binary DP Leonis A&A 526, 53 (2011) K. Beuermann1, J. Buhlmann2, J. Diese7, S. Dreizler1, F. V. Hessman1, T.-O. Husser1, G. F. Miller3, N. Nickol7, R. Pons7, D. Ruhr7, H. Schmülling7, A. D. Schwope8, T. Sorge7, L. Ulrichs7, D. E. Winget3 and K. I. Winget3 envelope binaries envelope Planetary systems of post common of systems Planetary 1) Göttingen, 2) Warwick, 3) Austin, 4) Valparaiso, 5) Tübingen, 6) Sheffield 7) Göttingen (MPG), 8) Potsdam AIP Post common enevelope binaries with companions • PCEB – result from spiraling in secondary in the RG envelope of the primary • Detection method – Eclipse-time variation by the light-travel time effect PLATO Meeting Berlin Meeting PLATO – – biased towards massive companions with long periods • Interpretation – Apparent period variation: third body, apsidal motion, beating between activity+orbital rotation – Real variation: magnetic braking, Applegate’s envelope binaries envelope Planetary systems of post common of systems Planetary mechanism, gravitational waves, ..... Post common enevelope binaries with companions • Systems – HW Vir 19 + 9 Mjup (Lee et al. 2009) – NN Ser 7+2 Mjup (Beuermann et al. 2010) – QS Vir 60 + 6 Mjup (Parsons et al. 2010) – V471 Tau 47 + ? Mjup (Kaminski et al. 2007) PLATO Meeting Berlin Meeting PLATO – HS0705 BD+?? Mjup (Qian et al. 2010) – – DP Leo 6 Mjup (Beuermann et al 2011) – HU Aqr Two ? (Schwartz et al. 2009) • Candidates (Parsons et al. 2010) – DE CVn – GK Vir envelope binaries envelope Planetary systems of post common of systems Planetary DP Leo PLATO Meeting Berlin Meeting PLATO – Period 282 yr Orbit 8.20.4 AU Mass 6.10.5 Mjup (Primary 0.6 + 0.1 Msun) envelope binaries envelope Planetary systems of post common of systems Planetary Eccentricity 0.390.13 DP Leo • Varying contribution of accretion spot • Timing accuracy of ~1sec +spot PLATO Meeting Berlin Meeting PLATO – +photosphere accretion stream envelope binaries envelope Planetary systems of post common of systems Planetary Planetary systems of post common envelope binaries – PLATO Meeting Berlin NN Ser Planetary systems of post common envelope binaries – PLATO Meeting Berlin NN Ser The 2+2-Body Solutions • Binary (0.535+0.111 Msun, P=3.1h, T=57kK) – Pdot < -10-13 (GR angular momentum loss OK) • Two stable 2+2 solutions (grid search) – Pc:Pd ≈ 2:1 ≈ 5:2 (±15%) – Reduced 2 0.90 0.91 • NN Ser c PLATO Meeting Berlin Meeting PLATO – ec 0 0 – – Pc [years] 15.50±0.45 16.73±0.26 – ac [A.U.] 5.38±0.20 5.65±0.06 – Mc sin i [MJupiter] 6.89±0.54 5.93±0.40 • NN Ser d – ed 0.20±0.02 0.22±0.02 – Pd [years] 7.75±0.35 6.69±0.40 – ad [A.U.] 3.39±0.10 3.07±0.13 envelope binaries envelope Planetary systems of post common of systems Planetary – Md sin i [MJupiter] 2.24±0.38 1.61±0.27 EB planets in Plato • Planets in binary systems to complete picture of planet formation and evolution • Circum binary proto-planetary disks, but no circum-binary planet around MS stars • Existence likely due to circum binary PLATO Meeting Berlin Meeting PLATO planets around PCEs – high-precision, un-interrupted, long- baseline eclipse time measurements of MS- binaries PLATO envelope binaries envelope Planetary systems of post common of systems Planetary Estimates of harvest • Minmum mass of companion • Number of targets: ASAS – 180 binaries in KEPLER field factor 10 more – 1000 in potential PLATO Field (RA=11h, DEC=-63) PLATO Meeting Berlin Meeting PLATO 10000 close binaries – envelope binaries envelope Planetary systems of post common of systems Planetary Implementation • Targets via – Input catalog – Variability classification – False positives from transit search • Challenges PLATO Meeting Berlin Meeting PLATO – Stellar variability – – Slight asynchronous stellar rotation • Benefit – Host star characterization from LC fits • Complements TTV, TDV envelope binaries envelope Planetary systems of post common of systems Planetary Conclusion • Complementing method • Probing a different class of planets • Large discovery space PLATO Meeting Berlin Meeting PLATO – envelope binaries envelope Planetary systems of post common of systems Planetary Planetary systems of post common envelope binaries – PLATO Meeting Berlin Planetary systems of post common envelope binaries – PLATO Meeting Berlin Planetary systems of post common envelope binaries – PLATO Meeting Berlin A school project … school A NN Serpentis • PG1550+131 (Wilson et al. 1986) • Porb = 3.12 hr (Haefner et al. 1989; MCCP) • VLT imaging, spectroscopy (Haefner et al. 2004) PLATO Meeting Berlin Meeting PLATO – Haefner et al. 1989 envelope binaries envelope Planetary systems of post common of systems Planetary Orbital Parameters Parsons et al. 2010a a = 0.934 R TWD = 57,000 K MWD = 0.535 M D = 512 pc 6 Msec = 0.111 M Age of WD ~ 10 yr i = 89.6° PLATO Meeting Berlin Meeting PLATO – envelope binaries envelope Planetary systems of post common of systems Planetary Eclipse Timing Residuals Qian et al. 2009 MCCP VLT Bialkow UltraCam Lijiang PLATO Meeting Berlin Meeting PLATO P = 7.6 years, a < 3.3 A.U., M = 11 MJupiter – envelope binaries envelope Planetary systems of post common of systems Planetary Eclipse Timing Residuals Parsons et al. 2010b PLATO Meeting Berlin Meeting PLATO MCCP – • Planetary solution rejected VLT • No satisfactory fit with linear Bialkow ephemeris UltraCam Lijiang • VLT point suspicious envelope binaries envelope Planetary systems of post common of systems Planetary Revisiting the VLT Observations • Trailed FORS images (Haefner et al. 2004) 1125.7462 secs PLATO Meeting Berlin Meeting PLATO – (±0.2 secs !) envelope binaries envelope Planetary systems of post common of systems Planetary Planetary systems of post common envelope binaries – PLATO Meeting Berlin MONET/North Observations MONET/North Timing Residuals MCCP VLT UltraCam Bialkow Lijiang MONET PLATO Meeting Berlin Meeting PLATO – envelope binaries envelope Planetary systems of post common of systems Planetary What the timing variations are not • Not due to complicated eclipse profile • Not due to stellar activity • Not due to Applegate’s mechanism – Spin-orbit coupling due to magnetic cycles and radius changes within the secondary – Time scale on decades or longer PLATO Meeting Berlin Meeting PLATO – – Needs too much energy (Chen 2009) • Not due to apsidal motion – Precession of periastron due to tides – Amplitude t = Pbin ebin = 3577 s ebin OK with ebin~0.01 – Variation of the FWHM not seen – Period would be ~0.4 years envelope binaries envelope Planetary systems of post common of systems Planetary Planetary systems of post common envelope binaries – PLATO Meeting Berlin McDonald Observations McDonald Planetary systems of post common envelope binaries – PLATO Meeting Berlin UltraCam Observations UltraCam Model #1 : 3rd Body PLATO Meeting Berlin Meeting PLATO – P = 22.6 years, e > 0.65 envelope binaries envelope Planetary systems of post common of systems Planetary a = 6.9 A.U., M = 8.4 MJupiter Planetary systems of post common envelope binaries – PLATO Meeting Berlin Model #2 : 2 Bodies #2 :2 Model The 2+2-Body Solutions • Binary – Pdot < -10-13 (GR angular momentum loss OK) • Two stable 2+2 solutions (grid search) – Pb:Pc ≈ 2:1 ≈ 5:2 (±15%) – Reduced 2 0.90 0.91 • NN Ser b PLATO Meeting Berlin Meeting PLATO – eb 0 0 – – Pb [years] 15.50±0.45 16.73±0.26 – ab [A.U.] 5.38±0.20 5.65±0.06 – Mb sin i [MJupiter] 6.89±0.54 5.93±0.40 • NN Ser c – ec 0.20±0.02 0.22±0.02 – Pc [years] 7.75±0.35 6.69±0.40 – ac [A.U.] 3.39±0.10 3.07±0.13 envelope binaries envelope Planetary systems of post common of systems Planetary – Mc sin i [MJupiter] 2.24±0.38 1.61±0.27 Orbital Histories of NN Ser A,B Red Giant Envelope PLATO Meeting Berlin Meeting PLATO 0.7 A.U. – 0.9 A.U. Common Envelope Ejection envelope binaries envelope Planetary systems of post common of systems Planetary Orbital History of NN Ser b,c • Binary Star System – ~2.1 Msun A star + M dwarf at ~1 A.U. (CE=0.25) – RGB expansion causes CE ejection ~1 million years ago – Planets around NN Ser A absorbed • 1st Generation (circumbinary): PLATO Meeting Berlin Meeting PLATO – – NN Ser b,c at > ~3 A.U. – Drift outwards/near escape due to loss of 1.5 M from NN Ser A – Differential drift inwards due to frictional drag (gravitational), tidal forces – Dynamical evolution stops at radii ~3 & 5-6 A.U. with resonance condition between b & c envelope binaries envelope Planetary systems of post common of systems Planetary Planetary systems of post common envelope binaries – PLATO Meeting Berlin A Primitive Evolution Simulation Primitive Evolution A Orbital History of NN Ser b,c • 2nd Generation (circumbinary) : – Original planets at a < ~1 A.U. lost in RGB – Formation of planets in the metal rich and massive CE with 1.5 M – NN Ser b,c come into resonance as very young planets PLATO Meeting Berlin Meeting PLATO • Mixed : – – Original planets at a < ~1 A.U. lost in RGB – Less massive planets at a ~ 2-6 A.U. survive CE and accretes from CE – 1st genaration plate might trigger planet formation in CE – NN Ser b,c come into resonance as rejuvinated/young planets envelope binaries envelope Planetary systems