Of serendipitous discoveries. Boris Gänsicke

Transcription

1 Of serendipitous discoveries Boris Gänsicke

2 1917: Van Maanen s star Ca H/K Carnegie Institution for Science Farihi 2016, NewAR 71, 9 Van Maanen 1917, PASP 29, , Cont. Mt. Wilson Obs. 182

3 The 3 rd closest white dwarf Fe Ca H/K Mg Ca d=4.4pc Carnegie Institution for Science Van Maanen 1917, PASP 29, , Cont. Mt. Wilson Obs. 182

4 White dwarfs 101 Rwd 0.01R R Mwd 0.65 M g~10 6 ms -2 g=9.8ms -2

5 White dwarfs are chemically stratified Pure H or He atmosphere Rwd 0.01R R Mwd 0.65 M g~10 6 ms -2 g=9.8ms -2 C/O core Althaus et al. 2010, A&A Rev 18, 471

6 The 3 rd closest white dwarf Fe Ca H/K Mg Ca d=4.4pc Carnegie Institution for Science Van Maanen 1917, PASP 29, , Cont. Mt. Wilson Obs. 182 External pollution, but where do the metals come from?

7 1987: G29-38, brown dwarf or dust? Zuckerman & Becklin 1987, Nature 330, 138

8 1987: G29-38, brown dwarf or dust? metal pollution Koester et al. 1997, A&A 320, L57

9 1987: G29-38, brown dwarf or dust? Zuckerman & Becklin 1987, Nature 330, 138

10 Jura 2003, ApJL 584, 91 The standard model Asteroids are scattered by unseen planets towards the white dwarfs Debes & Sigurdsson 2002, ApJ 572, 556

11 Off-topic: accretion discs in close WD binaries SDSS Balmer lines Horne & Marsh, 1986, MNRAS 218, 761 Littlefair et al. 2006, Science 314, 1578

12 2006: A typical white dwarf(?) H Gänsicke et al. 2006, Science 314, 1908

13 2006: A typical white dwarf - Not MgII FeII H CaII Gänsicke et al. 2006, Science 314, 1908

14 2006: A gaseous metallic debris disc MgII FeII Horne & Marsh (1986, MNRAS 218, 761) CaII H Gänsicke et al. 2006, Science 314, 1908

15 Jura et al. 2008, AJ 135, 1785

16 Wilson et al. 2014, MNRAS 445, 1878 Transient Ca II emission

17 2003 Indirect imaging of debris discs around white dwarfs 0.2R time 2.0R 2014 Manser et al. 2016, MNRAS 455, 4467

18 Chemical signature rules out accretion from the interstellar medium Jura 2006, ApJ 653, 613

19 Debris bulk abundances of exo-asteroids Zuckerman et al. 2007, ApJ 672, 871

20 Measuring bulk compositions in the solar system Meteor crater, Arizona

21 Measuring bulk compositions in the solar system Meteor crater, Arizona Jura & Young 2014, ARE&PS 42, 45

22 Detailed abundance studies O, Mg, Si, and Fe are the major constituents of the debris (and also make up ~93% of the Earth), variations similar to solar system Zuckerman et al. 2011, ApJ 739, 101 Melis et al. 2011, ApJ 732, 90 Klein et al. 2011, ApJ 741, 64 Gänsicke et al. 2012, MNRAS 424, 333 Jura et al. 2015, ApJ 799, 109 Xu et al. 2014, ApJ 783, 79 Jura & Young, 2014, ARE&PS 42, 1 Wilson et al. 2016, MNRAS 459, 3282

23 Detailed abundance studies O, Mg, Si, and Fe are the major constituents of the debris (and also make up ~93% of the Earth), variations similar to solar system Carbon-depleted, similar to bulk Earth rocky carbon depleted Zuckerman et al. 2011, ApJ 739, 101 Melis et al. 2011, ApJ 732, 90 Klein et al. 2011, ApJ 741, 64 Gänsicke et al. 2012, MNRAS 424, 333 Jura et al. 2015, ApJ 799, 109 Xu et al. 2014, ApJ 783, 79 Jura & Young, 2014, ARE&PS 42, 1 Wilson et al. 2016, MNRAS 459, 3282

24 Detailed abundance studies O, Mg, Si, and Fe are the major constituents of the debris (and also make up ~93% of the Earth), variations similar to solar system Carbon-depleted, similar to bulk Earth rocky Refractory litophiles Ca/Al very similar to solar system bodies same Al/Ca as in SS carbon depleted Zuckerman et al. 2011, ApJ 739, 101 Melis et al. 2011, ApJ 732, 90 Klein et al. 2011, ApJ 741, 64 Gänsicke et al. 2012, MNRAS 424, 333 Jura et al. 2015, ApJ 799, 109 Xu et al. 2014, ApJ 783, 79 Jura & Young, 2014, ARE&PS 42, 1 Wilson et al. 2016, MNRAS 459, 3282

25 Detailed abundance studies O, Mg, Si, and Fe are the major constituents of the debris (and also make up ~93% of the Earth), variations similar to solar system Carbon-depleted, similar to bulk Earth rocky Refractory litophiles Ca/Al very similar to solar system bodies Strong evidence for differentiation (Fe, S, Cr overabundance) iron-rich carbon depleted same Al/Ca as in SS Zuckerman et al. 2011, ApJ 739, 101 Melis et al. 2011, ApJ 732, 90 Klein et al. 2011, ApJ 741, 64 Gänsicke et al. 2012, MNRAS 424, 333 Jura et al. 2015, ApJ 799, 109 Xu et al. 2014, ApJ 783, 79 Jura & Young, 2014, ARE&PS 42, 1 Wilson et al. 2016, MNRAS 459, 3282

26 Mesosiderite-like exo-asteroids Mesosiderite Vaca Muerta origin from a ~ km differentiated asteroid (Scott et al. 2001, M&PS 36, 869)

27 What about water? Jura et al. 2009, ApJ 699, 1473 Jura & Xu 2010, AJ 140, 1129 Jura & Xu 2012, AJ 143, 6

28 2011:!?!? Koester et al. 2011, A&A 530, A114

29 Cool white dwarfs: planetary archaeology Ca Mg Na Teff=5500K Cooling age ~ 3Gyr! Ca Koester et al. 2011, A&A 530, A114

30 ~230 cool WDs Rich variety Of abundances Fe-rich Hollands et al. in prep Ca/Na-rich

31 2015: The first detection of debris transits Vanderburg et al. 2015, Nature 526, 546 metals dust

32 Large occulters ~3min duration R cloud 2-4R wd Average extinction 10% dm/dt ~ g/s Gänsicke et al. 2016, ApJ 818, L7

33 Large occulters Outburst on 67P/Churyumov Gerasimenko observed by ROSETTA ~3min duration R cloud 2-4R wd Average extinction 10% dm/dt ~ g/s Gänsicke et al. 2016, ApJ 818, L7

34 N-body tidal disruption setup Veras et al. 2016, MNRAS submitted

35 Homogenous, ρ = 2.6 g/cm 3 Differentiated, ρ = 3.5 g/cm 3 Total disruption within a few days Veras et al. 2016, MNRAS submitted Stable for >90 days, Intermittent mantle disruption

36 Differentiated, ρ = 3.5 g/cm 3, eccentricity = 0.0

37 Differentiated, ρ = 3.5 g/cm 3, eccentricity = 0.1 Veras et al. 2016, MNRAS submitted

38

39 They provide insight into the formation, physical properties, and evolution of exoplanets that is very complementary to main sequence systems

40 Mike Jura has been a continuous source of inspiration, and has been always a few steps ahead. He will be dearly missed.