Overview on Extra Solar Planets Rahul I. Patel PHY 599 – Grad Seminar Oct. 18 th 2010

Rahul I. Patel : Extrasolar Planets OUTLINE Motivation Current Theory Methods of Detection: –Radial Velocity –Direct Imaging –Others Results –Detected Exo-Planets Modified Theory Future Conclusion 2 Monday Oct. 18th, 2010

MOTIVATION

MOTIVATION : I, Human Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 4 Copernicus and Bruno (16 th Century) The Heliocentric Model 1995: “First” exoplanet  around 51 Pegasi < 10 yrs, instrument precision increased

MOTIVATION: For Science! Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 5 Advancement in observation technology  possibility of detecting planets - That hold life? Planet formation process Solar system evolution

Old Theory

PFT: Nebular Hypothesis Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 7

METHODS OF DETECTION

MOD: Radial Velocity Doppler shift of stellar spectral lines  COM orbit Detectors: HARPS, HIRES High S/N ratio Range: D max= ~160 Ly Observations may take years due to SMA distance Estimate planet minimum mass Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 9

Planets of the RV : HD planets around HD ( 0.86 M ☉ ) HD 69830: d = 12.6 pc, ST = K0V, V = 5.95 Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 10

Planets of the RV : Gliese 581 Gliese 581: M3V star: Red 20 Ly RV survey over 15 years (HIRES, HARPS)  6 companions Gliese 581g  min mass: 3.1 M AU, P = 36.6 days Within habitable zone, T est ~ 228K Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 11

Planets of the RV : Gliese 581 Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 12 b,c,d,e  Confirmed f, g can’t be confirmed by separate team using HARPS data Signal amplitude of ‘g’ very low  level of measurement noise

MOD: DIRECT IMAGING Actually SEE orbiting planets  not indirect Problem: Host Star Need >M J, Large SMA distance, and Extremely hot for IR radiation -  HIGH CONTRAST Problem: –Diffracted Light: optical diffraction, imperfect optics, residual wave front error New Methods: Coronagraphs Adaptive Optics Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 13

DIRECT IMAGING: Coronagraphs Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 14 Device to block light to resolve nearby objects 1930  Bernard Lyot

DIRECT IMAGING: Adaptive Optics Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 15 The binary star IW Tau is revealed through adaptive optics. The stars have a 0.3” separation. The images were taken by Chas Beichman and Angelle Tanner of JPL.

Planets of Direct Imaging Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 16 Fomalhaut b 2.1 M ☉, 1-3E7 yr, 8,751K, A3V 11/13/08  1 st directly imaged planet in V band (HST) M J 115 AU, T = 872 yrs e = 0.11 HR 8799 b,c,d HR 8799a: 1.5 M ☉, ~60Myr, 39 pc, F0V Debris disk : 3 planets

Other Methods… Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 17 Transit Astrometry Microlensing Pulsar Timing Transit Astrometry

Best Case… Combine multiple methods for meaningful analysis: - RV : Mass - Transit: Radius  Density, Transit Spectroscopy - Direct Imaging  Photometry  Temperature  Atmospheric composition Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 18

RESULTS

RESULTS Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 20

RESULTS Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 21

RESULTS Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 22

Alternate Planet Formation Theories

PFT: Exo-Planets Shake Things Up Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 24 Giant exo-planet (M J ) detected with T :[1.2 days, ~10 yrs] - M J planets w/in Frost Line Comet like eccentricities of some planets Some planets as massive as 15 M J  Heresy to call them planets?

PFT: Alternate Models I Core Accretion Model: –Solid core from accreting planetismals –Becomes massive enough to bind gas into envelope –After critical value, envelope starts to contract, increasing gas accretion rate, raising radiative energy loss  rapid buildup of massive envelope –Need critical core mass before protoplanetary disk disappears  ~1-10 Myr Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 25

PFT: Alternate Models II Direct Collapse Model - Giant planets form from gravitational fragmentation, collapse of disk in timed intervals Migration - time scales short  should fall into host star - Since Jupiter mass planets observed, migration model incomplete - slowed down due to : tidal interactions with host star (might also cause high eccentricity) - does not explain giants at intermediate distances, or why Jupiter remains at 5 AU Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 26

Future Work

FUTURE WORK: Extreme AO Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 28 Find planets in Debris Disks: High contrast ratio Keck NGAO (10 m) Palm 3000 at Palomar(5 m)  1 st Extreme AO (2011) (JPL and Caltech) – Precision near-IR photometry and astrometry –High contrast imaging and high sensitivity faint-object visible light imaging.

FUTURE WORK: JWST Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 29 Thermal IR 5–25 µm Warm Planets

CONCLUSION Several methods of detection –Transit, Radial Velocity Survey, Astrometry, –Direct Imaging Odd ball planets all over the place No obvious pattern Reformulation of planetary formation Future Missions: KEPLER, JSWT, Palomar PALM 3000 Monday Oct. 18th, 2010 Rahul I. Patel : Extrasolar Planets 30

References Lovis, C. et. al. An extrasolar planetary system with three Neptune-mass planets. Nature 441, (18 May 2006). Marcy, G. et. al. Observed Properties of Exoplanets: Masses, Orbits, and Metallicities. Progress of Theoretical Physics Supplelement 158 (2005). Mordasini, C. et. al. Extrasolar Planet Population Synthesis I. Method, formation tracks, and mass-distance distribution. A&A 501, 1139–1160 (2009) Santos, N. et. al. Extrasolar Planets: Constraints for Planet Formation Models. Science 310, 251 (2005). Udry, S. et. al. Statistical properties of exoplanets I. The period distribution: constraints for the migration scenario. A&A 407, 1 (2003) S. Hinkley, B. Oppenheimer, High contrast observations in Optical and Infrared Astronomy. Annu Rev. Astro Astrophysics,