No wide companions up to 700AU!

1. NTT/SOFI NACO+SDI/VLT Common proper motion confirmed Orbital motion detected! 21AU No wide companions up to 700AU!

2. GJ86B co-moving bound to GJ86A faint MH=14.2mag but hot T>3800K -> a white dwarf! Mugrauer & Neuhäuser, MNRAS, May 2005

3. 7+ new binaries found, M dwarf companions to rad vel planet (candidate) host stars. • Extension of sample by at least 30%. • A second white dwarf companion found. Mugrauer et al. , 2005, in prep. telluric telluric telluric

4. Direct imaging of planets and brown dwarfs around young, single and binaries stars Ralph Neuhäuser (Astrophysical Institute University Jena) with Eike Guenther (TLS Tautenburg) G. Wuchterl, M. Mugrauer, A. Bedalov (AIU Jena) P. Hauschildt (Uni Hamburg)

5. TWA-5 B TWA-5 B Abstand zum Stern: z.B. 10 AE (1 arc sec in 10 pc) (0.2 arc sec in 50 pc) 8.2m-VLT (Fors2) 3.5m-NTT(Sofi) Direct detection of Exo-Planets: The problem of dynamic range Problem of dynamic range: Planet too faint and too close to star !!!

6. 55 mas binary ! (Neuhäuser, Potter, Brandner 2001 Conf. Proc.) (Potter, ..., Brandner, Neuhäuser 2002 ApJ) TWA-5 A & B: FWHM = 0.064 arc sec, 30% Strehl (H-Band) H=17 at 1“ (5 Jup, 60 AU) HD 130948 (200 Myrs, UMa moving group) with 2 brown dwarfs (early L, H=12), 0.13“ separation, i.e. 2.5 AU in 18 pc. 10 year orbit, then dynamical masses ! VLT/FORS 2 0.180 arc sec Brown dwarfs around young stars (Hokupaa at Gemini North):

7. Another case: Brown dwarf companion to A0-type star HR 7329 (TucHorA or beta Pic) spectral type M7-8 Guenther et al. 2001

8. Next case: GSC 8047 in HorA VLT-ISAAC H- and K-Band, 0.8“ slit companion has spectral type ~ M8, Brown dwarf with 20 Jup mass, 35 Myrs, 85 pc (Neuhäuser & Guenther 2004, A&A)

9. 0.7 arc sec 0.7 arc sec 0.7 arc sec HST WFPC2 F814W (I-band) 1999 VLT NaCo Ks-band 2004 Subaru CIAO L-band 2002 Companion candidate near GQ Lupi Host star is classical T Tauri star, 140 pc, 1-2 Myr, IR excess (disk)

10. HST Subaru NACO

11. if companion

12. if companion plus/minus orbital motion

13. if background if companion

14. 7s 5s Clearly a common-proper-motion pair ! if background (proper motion with parallactic wobble) if companion

15. (possible) change of position angle from HST to VLT observation Co-moving ! HST VLT background ? 7 sigma

16. VLT NACO K-band spectra (Aug & Sept 2004) Log g from CO lines (Gorlova et al. 2003)  log g = 2.5 +/- 0.8 spec type ~L2 Fit of observed spectrum to Hauschildt model atmosphere gives: log g = 2 – 3, T = 2000 K. Flux at 140 pc yields radius ~ 1.2 R_jup  hence, a mass of 0.5 to 6 M_jup !!!

17. Wuchterl & Tscharnuter 2003 conventional stars brown dwarfs planets Log10 L / Lsun Jupiter Log10 Age (yrs) Burrows et al. 1993, 1997

18. The Wuchterl & Tscharnuter (2003) models take into account and start with the collaps itself. Results: Primary star and companion are co-eval at ~ 1.1 Myr. Primary star ~ 0.7 solar masses. Companion mass: 1 to 3 Jup masses (1s) for companion: log g = 2.2 to 2.6 Companion planet or brown dwarf ?

19. ~ 2 Jup radii M < 8 Jup masses Radius – mass diagram (Mohanty, Basri, et al. 2004 ApJ)

21. HRD Bonnor-Ebert Isochrones + Basri-Mohanty Properties

22. A third object in the GQ Lupi system ? 4 week monitoring with 8 min/night at CTIO (2005) (data from Schwartz & Noah, Appen- zeller et al., Bertout et al., 1977/78) Preliminary rad vel curve (Feros and Harps) … an inner planet ? (Eike Guenther) Result: 8.41 day rotation period with two bright spots ! 8.41 day period, but only one spot. Broeg, Guenther, Neuhäuser, Gaedke, Bedalov, Schmidt, Walter, in prep.

23. 213 objects within 0.25 squ.deg, around GQ Lup and their proper motions same proper motion for GQ Lupi A & b, but not bound ? In an association or moving group, most members do have the same proper motion, so that co-moving nearby objects are not neccessarily bound (Neuh. et al. 2002) Probability to find one new object within 0.7 arc sec around GQ Lup is very small, below 0.06 % (considering faintness and spectral type, even below 0.000006 %). • Cumulative distribution function of binary separations in Lupus (Nakajima, Tachihara, et al. 1998) • 0.116 objects with sep = 0.7“ in Lupus, but we found 1 ! • break point at 1110 AU as mean nearest neighbor, but we have 100 AU proj. phys. sep. !

24. Chauvin et al. (2004): A planet of 2M1207 ? 2M1207: a potential brown dwarf member of TWA, 5 to 12 Myrs, 50 to 100 pc Faint object detected next to it with VLT/NaCo HKL color and H-band continuum consistent with mid- to late-L  5 Jupiter masses !?! Common proper motion confirmed (Chauvin et al. 2005)

25. GQ 2M1207b M9 – L4 L5-9 Comparing GQ Lup b and 2M1207 b Observational evidence: GQ Lup b: Spec type M9 - L4  T = 1600 – 2500 K (Neuhäuser et al. 2005) 2M1207b: Spec type L5 – L9  T = 1200 – 1950 K (Chauvin et al. gave 1000 – 1500 K) (Gorlova et al. 2003) Common proper motion, but … GQ Lup A + b: co-moving with 17 sigma. Expected orbital motion 3.7 +/- 1.5 mas/yr. Observed motion is 5.2 +/- 2.1 mas/yr. Escape velocity 1.4 +/- 2.2 mas/yr.  ok. 2M1207 A + b: Observed motion 4.1 +/- 8.2 mas/yr. Escape velocity 2.7 +/- 0.9 mas/yr.  ? And what about long-term stability ?

26. Criteria for long-term stability: Weinberg et al. 1987, Close et al. 2003

27. Conclusions / summary: • Brown dwarf companions exist around 6 +/- 4 % of young A- to M-type stars (sometimes hierachical triples) (Neuhäuser & Guenther 2004 A&A) • Massive (> 5 Jup), wide (> 50 AU), young (< 100 Myrs) planets are rare: < 9 % (Neuhäuser et al. 2003 AN) • Problem: Mass (and, hence, nature) of wide companion by theoretical model (to be tested and calibrated)  No evidence for 3rd object in GQ Lupi system, but 8.4 day period. • GQ Lupi companion very low-mass (< 8 Jup), probably bound and long-term stable.

29. Spectral energy distribution of the classical T Tauri star GQ Lupi Strong IR excess  envelope or disk

30. weighted mean Different proper motions published for GQ Lupi

31. VLT NACO K-band spectra (Aug & Sept 2004) Compare Hauschildt AMES/GAIA-Dusty model: T = 2000 K, log g = 2 to 3, and ~ 1 - 2 Jupiter radii

32. (Golimowski et al. 2004) L2  B.C. = 3.3 and T = 2000

33. Observational evidence: K= 13.1 mag Common proper motion with classical T Tauri star Spectral type M9-L4 (consistent with K-L color)  T = 2050 +/- 450 K Comparison with model spectra  T = 2000 K and log g = 2 to 3 Interpretation: Common proper motion  same age and distance as primary: 1 Myr at 140 pc Magnitude with B.C. for M9-L4 at 140 pc  luminosity Luminosity and temperature at 1 Myr  Mass … (via theoretical model tracks)

34. Burrows et al. 1997 Fig. 7: Age and luminosity  12 to 32 Jup masses Stars 0.08 Suns = 80 Jupiter Brown dwarfs Log10 L / Lsun Planets 13 Jup Jupiter Log10 age (yrs) Burrows et al. 1997

35. Burrows et al. 1997 Fig. 10: Temperature and age  3 to 9 Jup masses Burrows et al. 1997 Fig. 9: Temperature and age  3 to 9 Jup masses

36. 11 to 42 Jup masses 3 to 16 Jup masses (Baraffe et al. 2002 Fig 2) Baraffe et al. 2002 Fig 1: 1 – 20 Jup masses, ~ 1 Myr The Lyon group models: Baraffe & Chabrier Chabrier et al. 2000 Fig. 2 below 20 Jup mass Baraffe et al. (2002): „Assigning an age (or mass) to objects younger than a few Myrs is totally meaningless … models are too uncertain.“

37. Suggested definition: A planet is a metall rich non-fusor born in orbit around a fusor or former fusor (at least as massive as the lowest mass planet in the solar system). Definition (Vorschlag): Ein Planet ist ein metallreicher Nicht-Fusor geboren im Orbit um einen Fusor oder Ex-Fusor (mindestens so massereich wie das massearmeste Planet im Sonnensystem).

38. Burrows et al. 1997 Fig. 7: Age and luminosity  12 to 32 Jup masses (GQ Lup b) 2M1207b Stars 0.08 Suns = 80 Jupiter Brown dwarfs Log10 L / Lsun Planets 13 Jup Jupiter Log10 age (yrs) Burrows et al. 1997

39. Burrows et al. 1997 Fig. 10: Temperature and age  3 to 9 Jup masses (GQ) Burrows et al. 1997 Fig. 9: Temperature and age  3 to 9 Jup masses (GQ Lup b)

40. 11 to 42 Jup masses 3 to 16 Jup masses (Baraffe et al. 2002 Fig 2) Baraffe et al. 2002 Fig 1: 1 – 20 Jup masses, ~ 1 Myr The Lyon group models: Baraffe & Chabrier Chabrier et al. 2000 Fig. 2 below 20 Jup mass According to Chabrier et al. (2000) and Baraffe et al. (2002), when using correct temperarure range, also 2M1207b could either be planet or brown dwarf (like GQ Lup b).

41. 2M1207 A 2M b The Wuchterl & Tscharnuter (2003) models take into account and start with the collaps itself.

42. The Deuterium test: Planet or brown dwarf ? R=100000 CRIRES, eps Indi B, L=9 mag, S/N=100, R=100000, 3 hours CH3D (Neuhäuser & Hauschildt, in press, ESO Crires Conf. Proc.)

43. Structure at AIU • Two professorships: Alexander Krivov (theory) • Ralph Neuhäuser (observation) •  Laboratory astrophysics: Harald Mutschke, Hans Dorschner Post-doc: Conny Jäger PhDs: Isabel Llamas, Akemi Tamanai Students: Susann Humnmel (close collaboration with solid state physics Jena and MPI Heidelberg) • formation of stars (radio/mm/IR): Post-docs: Katharina Schreyer PhDs: Jan Forbrich Students: Tobias Schmidt • observtion / formation of young sub-stellar objects and disks: Ralph Neuhäuser, Marc Hempel, Katharina Schreyer PhDs: Matthias Ammler, Markus Mugrauer, Ana Bedalov Students: Manuela Wiese, Ansgar Gaedke, Michel Schneider, Tristan Roell • Neutron stars (collaboration with MPI Garching, Hasinger): Ralph Neuhäsuser und Bettina Posselt • Theory of star and planet formation: Post-doc: Günther Wuchterl PhDs: Christopher Broeg, Bojan Pecnik Student: Johannes Schönke, Sebastian Krause  New theory group around Alex Krivov being build up now !!!

44. Tachihara et al. 1996, PASJ 48

45. The differential imaging with NACO/SDI Mugrauer & Neuhäuser, MNRAS, 2005

46. Mugrauer, Neuhäuser, et al., A&A, 2005

47. Astrometry Radial velocity CORAVEL Jahreiß 2001 linear trend 0.5ms-1d-1 Dmacos(d)=58.15+-1.43 mas/yr Dmd=17.15+-1.35 mas/yr Queloz A&A 2000 1980 2000 year