ge/ay133 what have radial velocity surveys told us about (exo)-planetary science?
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Ge/Ay133
What have radial velocity surveys told us about (exo)-planetary science?
Mayor, M. & Queloz, D. 1995, Nature, 378, 355
Udry, S. et al. 2002, A&A, 390, 26
Jovian planetsthrougout the0.05-5 AU region.
And…
No strong preference for orbital distances…
…except for a“pile up” of hotJupiters at P~3 days.
Planetary characteristics? Some trend in M versus R (bias?), butbeyond 0.05-0.1 AU, little preference for low eccentricities:
Butler, R.P. et al. 2006, ApJ, 646, 505
Even with incompleteness, strong preference for ~Jovian mass:
Butler, R.P. et al. 2006, ApJ, 646, 505
Stars are different, turnover at low mass!
“The brown dwarf desert”?
Does this tell usthat stars and planets formdifferently?
Orion IMF
Is there an eccentricity preference w/mass? Not really…
Marcy, G. et al. 2005, astro-ph/0505003
Is there an eccentricity preference w/mass? Not really, part II…
Butler, R.P. et al. 2006, ApJ, 646, 505
?
Another clue as to formation: Planet formation efficiency correlates strongly with metallicity!
Fischer, D.A. & Valenti, J. 2005, ApJ, 622, 1102
What about planetary multiplicity? Complex doppler patterns:
Summary of known multiple planetary systems:
Marcy, G. et al. 2005, astro-ph/0505003
A super earth & GJ 876? Rivera, E.J. et al. 2005, (see class web site)
GJ 876 orbitsevolve with time (expected w/mutual perturbations)!
What about other systems?
Rivera, E.J. et al. 2005, (see class web site)
HD 168443a: 7.2 Mj 58 daysb: 17 Mj 1739 days
=1/29.98 ?!30:1?
HD 12661a: 2.3 Mj 263 daysa: 1.6 Mj 1444 days
=1/5.511:2?
47 U Maa: 2.5 Mj 1089 daysb: 0.76 Mj 2594 days
=1/2.4
Gleise 876a: 1.89 Mj 61 daysb: 0.56 Mj 30 days
HD 37124a: 0.75 Mj 152 db: 1.2 Mj 1495 d
ups AndA: 0.69 Mj 4.6 dB: 1.9 Mj 241.5 dC: 3.75 Mj 1284 d
HD 82943A: 1.63 Mj 444 dB: 0.88 222 d
55 CncA: .84 Mj 14.6 dB: 0.21 Mj 44.3 dC: 4 Mj 5360 d
3:1!
What we know:- ~1% of solar-type stars have Hot Jupiters
-~7% of solar-type stars have >Mj planets in the “terrestrial planet” region. Extrapolation of currentincompeteness suggests ~12% w/planets @ <20 AU.
- multiple planetary systems are ~common
- planetary resonances are ~common
What can explain these properties?
Disk-star- and protoplanet interactions lead to migration while the gas is present. Core- accretion?
Theory
1 AU at 140 pc subtends 0.’’007.
Jupiter (5 AU):V_doppler = 13 m/sV_orbit = 13 km/sSimulation G. Bryden, JPL
Thus, need to study objects in this phase…
Core-accretion models can now be compared to observations:
Planetsversusmetallicity:
Data
Observedin opencircles.
Ida, S. & Lin, D. 2004, ApJ, 616, 567
Early disk models held that eccentricities were DAMPED. Not so fast…
Goldreich & Sari 2005
Need aninitiale~0.01.
Goldreich, P. & Sari, R. 2003, ApJ, 585, 1024