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High Cadence Searches for Extrasolar Planets The discovery of extrasolar planets in the past decade was one of the most remarkable achievements of the century, and the culmination of centuries of speculation. National Academy of Sciences, Decadal Review of Astrophysics
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Planet Mass Distribution Fit Excludes 1 st bin. Detection Limit: ~ 0.2 M JUP @ 1 AU Five Neptunes: Gl 436 Gl 436 55 Cnc d 55 Cnc d Ara Ara HD 190360 HD 190360 Gliese 581 Gliese 581 Butler et al. Butler et al. McArthur et al. McArthur et al. Santos et al. Santos et al.
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Planet – Metallicity Correlation Abundance Analysis of 1000 stars on planet search. 2 P planet ~ ( N Fe / N H ) Previous Evidence: G.Gonzales, N.Santos Fischer & Valenti 2005 Metallicity Models: Ida & Lin Ida & Lin Kacper Kornet Kacper Kornet et al. et al.
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© NSF/NOAO 7000 Å 4000 Å
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Dr. Gillian Nave, NIST
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Key to Doppler Measurements: Wavelength Calibration 4995 – 6000 Ang. 4995 – 6000 Ang. Thousands of I 2 lines Thousands of I 2 lines 3 m/s Precision 3 m/s Precision Spectrometer PSF: Spectrometer PSF: Conveyed by I 2 line Conveyed by I 2 line shapes. shapes.
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The Next Decade: 3 m/s versus 1 m/s 1 m/s 3 m/s Jupiter analog is 10-sigma detection Uncertainty of eccentricity is +/-0.02 Saturn-mass at 5 AU is a 4-sigma detection Super-Earths detectable in 4-day orbits Detection sensitivity similar/better than SIM Minimal (3-sigma) detection of Jupiter analog Eccentricity of Jupiter analog is uncertain (+/-0.2) Non-detection of Saturn-mass at 5 AU Obstacles to 1 m/s Stellar oscillations Photons Stellar granulation Systematic Errors Stellar rotation
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P-modes in Solar-type stars Amp ~ 1.5 m/s Per = 5 min - Seismology - Seismology -Noise: Avg over Avg over P-modes ! P-modes ! Alpha Cen A (G2 V)
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K dwarfs: 1 meter/sec Acoustic p-modes: Amp < 1 m/s Alpha Cen B (K0V)
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10 Earth-Masses P = 50 day Single telescope Aliasing 1 day Obs.
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5 Earth-Masses P = 50 day 5 Earth-Masses P = 50 day Single telescope
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1 Earth-Mass P = 4.2 d M star = 0.5 M O
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Magellan Planet Finder Spectrograph Jeff Crane (OCIW) Steve Shectman (OCIW) Paul Butler (DTM) Ian Thompson (OCIW)
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1722 March 2008Magellan SAC Optical layout R4 grating fresnel+PMT prism collimator + camera fold mirrors f/11 telescope focal surface guid er CCD f/11 to f/5 beamsplitte r slit ThAr & QTH lamps
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Constant gravity environment Constant gravity environment Athermalized optical train Athermalized optical train High efficiency (35%) High efficiency (35%) = 100,000 (for 1 arcsec slit) Passively compensated space-frame Passively compensated space-frame 1 m/s velocity precision 1 m/s velocity precision Cost: $2 million (NASA) Cost: $2 million (NASA) The APF Planetometer A high resolution spectrometer optimized for ultra-precision radial velocity work for ultra-precision radial velocity work Telescope Beam
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The result of littrow echelle, prism CD, and all-dioptric system
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Exoplanet Target Stars Activity Spectral Type Chromospherically quiescent: R’hk < -4.8 F8V and later
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1 m/s: Long View Keck 12+ nights per semester AAT 25+ nights per semester Mag 25+ nights per semester APF 82+ nights per semester Every Saturn mass planet out to 9 AU Every Neptune mass planet out to 1 AU Super-Earths out to 0.3 AU Earth-mass planets out to 0.1 AU Solar System analogs Habitable planets
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People More Important Than Me: Steve Vogt, UCSC Steve Vogt, UCSC Steve Shectman, Carnegie Observatories Steve Shectman, Carnegie Observatories Jeff Crane, Carnegie Observatories Jeff Crane, Carnegie Observatories Chris Tinney, UNSW Chris Tinney, UNSW Hugh Jones, U of Hertfordshire Hugh Jones, U of Hertfordshire Greg Laughlin, UCSC Greg Laughlin, UCSC Dante Minniti, Catolica Santiago Dante Minniti, Catolica Santiago Pamela Arriagada, Catolica Santiago Pamela Arriagada, Catolica Santiago
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