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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 Planet Mass Distribution Detection Limit: ~ 0.2 MJUP @ 1 AU Five Neptunes: Gl 436 55 Cnc d m Ara • HD 190360 • Gliese 581 Butler et al. McArthur et al. Santos et al. Fit Excludes 1st bin. Planet – Metallicity Correlation 2 Pplanet ~ (NFe/ NH) Fischer & Valenti 2005 Previous Evidence: G.Gonzales, N.Santos Abundance Analysis of 1000 stars on planet search . Metallicity Models: Ida & Lin Kacper Kornet et al. 7000 Å 4000 Å © NSF/NO Dr. Gillian Nave, NIST Key to Doppler Measurements: Wavelength Calibration 4995 – 6000 Ang. Thousands of I2 lines 3 m/s Precision Spectrometer PSF: Conveyed by I2 line shapes. The Next Decade: 3 m/s versus 1 m/s 3 m/s Minimal (3-sigma) detection of Jupiter analog Eccentricity of Jupiter analog is uncertain (+/-0.2) Non-detection of Saturn-mass at 5 AU 1 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 Obstacles to 1 m/s Stellar oscillations Stellar granulation Stellar rotation Photons Systematic Errors P-modes in Solar-type stars Alpha Cen A (G2 V) Amp ~ 1.5 m/s Per = 5 min - Seismology -Noise: Avg over P-modes ! K dwarfs: 1 meter/sec Alpha Cen B (K0V) Acoustic p-modes: Amp < 1 m/s 10 Earth-Masses P = 50 day Aliasing 1 day Obs. Single telescope Single telescope 5 Earth-Masses P = 50 day 1 Earth-Mass P = 4.2 d Mstar = 0.5 MO Magellan Planet Finder Spectrograph Jeff Crane (OCIW) Steve Shectman (OCIW) Paul Butler (DTM) Ian Thompson (OCIW) f/11 telescope focal surface f/11 to f/5 Optical layout ThAr & QTH lamps slit CCD R4 grating guid er beamsplitte r 22 March 2008 fold mirrors prism collimator + camera Magellan SAC fresnel+PMT 17 The APF Planetometer A high resolution spectrometer optimized for ultra-precision radial velocity work Constant gravity environment • Athermalized optical train • High efficiency (35%) l/Dl = 100,000 (for 1 arcsec slit) • Passively compensated space-frame • 1 m/s velocity precision • Cost: $2 million (NASA) • APF Predicted Efficiency The result of littrow echelle, prism CD, and all-dioptric system 0.4 0.35 0.3 Efficiency 0.25 0.2 0.15 0.1 APF System Efficiency HIRES (2005) 0.05 UVES + KUEYEN (2005) 0 0.3 0.4 0.5 0.6 0.7 Wavelength (microns) 0.8 0.9 1 Exoplanet Target Stars Spectral Type F8V and later Activity Chromospherically quiescent: R’hk < -4.8 1 m/s: Long View Keck AAT Mag APF 12+ nights per semester 25+ nights per semester 25+ nights per semester 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 People More Important Than Me: Steve Vogt, UCSC Steve Shectman, Carnegie Observatories Jeff Crane, Carnegie Observatories Chris Tinney, UNSW Hugh Jones, U of Hertfordshire Greg Laughlin, UCSC Dante Minniti, Catolica Santiago Pamela Arriagada, Catolica Santiago