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A Global Network for Planet Detection and Asteroseismology Study using Extremely high Precision Extrasolar Planet Tracker Instruments. Jian Ge, University of Florida. UF team members:
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A Global Network for Planet Detection and Asteroseismology Study using Extremely high Precision Extrasolar Planet Tracker Instruments Jian Ge, University of Florida UF team members: Bo Zhao, John Groot, Liang Chang, Xiaoke Wan, Frank Varosi, Scott Powell, Kevin Hanna, Peng Jiang, Scott Fleming, Brian Lee, Rohan Pais, Ji Wang, Liming Dou, Jian Liu, Erin Costello, Adriana Delgado-Navarro, Sandeep Reddy Bollampally, Troy Bosman, Sid Schofield, Bo Ma, & Hali Jakeman EXPERT Network International Members: T. Wang (China team leader), J.L. Zhou, W.M. Yuan, H.Y. Zhou, J.M. Bai, Y.F., Fan., S.H. Gu, & E. Martin (Spanish team leader)
Strategy for Building a Global Doppler Network • Take advantage of retiring 2 meter telescopes and convert them into semi-dedicated telescope network for long term surveys • Develop low-cost, compact, robust, low maintenance, but high precision and throughput Doppler instruments • Target bright F,G,K dwarfs (V<8) with slow rotation for detection of super Earth mass planets, including habitable ones • Integrate at least 15 min to minimize RV noises from stellar oscillations for low mass planet detection • A nearly perfect match of ~15 min exposure time requirements and photon noise limit offered by a 2 meter telescope for 0.5-1 m/s • For asteroseismology, only target V<5 stars and ~1 min exposures Key: new technology Doppler instruments
Australia ? Hawaii ? Chile ? Global Extremely High Precision Exoplanet Tracker Network Spain SET, 11? USA EXPERT, Sept. 09 China LiJET, June, 10 • Offer continuous high precision radial velocity measurements for V<8 FGK stars with 0.5-1 m/s Doppler precision in 30 min • Follow up planet candidates from SDSS-III MARVELS planet survey • Compact and low cost design (~$750K per instrument including hardware and labor; cost may be further reduced for smaller telescopes)
High Precision RV Mode Prism Echelle 4kx4k CCD Collimator-camera Slit Output 1 Output 2 Fiber input Michelson Interferometer • A combination of a fixed-delay interferometer with a high throughput cross-dispersed echelle spectrograph with R=18,000 • A simultaneous wavelength coverage of 0.39-0.70 m • 0.5-1 m/s in 30 min for V< 8 solar type stars with 2 m telescopes 4
Fixed-delay Interferometer Doppler Principle Fringe order and delay relationship: Fringe shift caused by wavelength change: Doppler shift and phase shift relationship:
DFDI principle Stellar spectrum x comb ET spectrum Credits: Julian van Eyken
Direct Cross-dispersed Echelle Mode Prism Echelle 4kx4k CCD Collimator-camera Slit Fiber input • The cross-dispersed echelle spectroscopy mode with R=27,000 and a simultaneous wavelength coverage of 0.39-1.0 m 7
Primary targets for EXPERT network Photon limited RV precision in 30 min exposures with EXPERT Magnitude RV precision V=6 0.4 m/s V=7 0.6 m/s V=8 1.0 m/s
Detection of Earth-like short period planets with 1 m/s Doppler precision Credit: S. Kane • 2 Earth mass planet, 2.2 day period around a solar type star, K= 1m/s • = 1m/s, 60 measurements, clear detection with 0.1% FAP • Need good orbital phase coverage to eliminate other noises
Opt-mechanical layout of EXPERT Thermal enclosure Pressure controlled chamber Interferometer Echelle Input fiber feed Prism 4kx4k CCD camera Collimator/camera • The thermal enclosure dimension: 69" x 45" x 39.9". • Temperature and pressure controlled • Goals to reach ~2mpsi, ~4 mK and <10 m/s drift over 1 week
EXPERT hardware setup at Kitt Peak 2.1m in Sept. 2009 EXPERT inside a 2.1m Coude room EXPERT control chassis
EXPERT inside a Thermally Controlled Chamber at Kitt Peak in Sept. 2009 Thermal enclosure Chamber Interferometer RV input fiber Echelle DEM input fiber Prism Collimator/Camera 4kx4k CCD Pressure sensor
Solar Spectra on the Detector with EXPERT Order 29, 0.70 m Output 2 Order 52, 0.39 m Order 29, 0.70 m Output 1 Order 52, 0.39 m
Early RV measurement results with EXPERT Observations with Iodine absorption Observations with sky Photon error =1.3m/s with 12 orders combined Photon error =1.2m/s with 12 orders combined Observations with 51 Peg Photon error =4.7m/s with 9 orders combined
Cross-dispersed echelle spectra of NSV 860 (K2 EB, V=8.7) in Jan. 10 R=27,000 Order 52, 0.39 m Order 20, 1.0 m
RV Drifts vs. Pressure and Temperature variation with EXPERT in Oct. 2009 RV vs Pressure RV Pressure RV vs Temperature RV Temperature • Need to control pressure and temperature to reach higher RV stability
EXPERT Instrument Temperature Monitoring in Dec. 2009 • Instrument temperature varies within 10 mK over 5 days
EXPERT Instrument RV Monitoring in Mar. 2010 RV vs pressure in 4 days RV vs temperature in 4 days 12 mk 50 m/s 100 mpsi RMS=1.4m/s with Iodine calibration
LiJET hardware setup at the UF lab in Jan. 2010 LiJET setup in the UF lab LiJET inside a 2.1m Coude room
LiJET Instrument Temperature Monitoring in Mar. 2010 15 mK 3mpsi
Exoplanet Tracker Network Plan • Science operation • Science operation with EXPERT at Kitt Peak in April 2010 • Science operation with LiJET at Lijiang, China in September 2010 • Complete the Spanish Exoplanet Tracker (SET) in early 2011 pending on remaining fund raising and telescope negotiation • Primary science targets • V<8 FGK main sequence stars with slow rotation and low activities for super Earth mass planet detection and characterization • Followup of MARVELS planet and brown dwarf candidates to confirm and characterize new giant planets and find additional planet companions • A few very bright solar type stars (V<5) for asteroseismology study • Future plan • Looking for more partners to complete 6 network instrument development and implementation • Raising federal, state and private funds for operating the network • Combining with up-coming space transit missions for bright stars to detect and characterize habitable rocky planets
The Multi-object Optical Doppler instrument at SDSS in Sept 08 MARVELS Plugging Plate MARVELS-I inside an air condition room Instrument Calibration box MARVELS Fibers Control box
MARVELS RV drift 20 m/s 5 mK • RV drift is about 20 m/s over ~3 days • Temperature change is about 5 mK over ~3days.
Discoveries of Two Brown Dwarfs by MARVELS A new brown dwarf with 20 Jupiter masses and 5.9 day period A new brown dwarf with 50 Jupiter masses and 5.8day period Lee et al. 2010, ApJ submitted Fleming et al. 2010, submitted
Planet Candidates by MARVELS V=9.2, Teff=4866K, logg=3.5 P=80.2days, Msini=1.9MJ V=11.3, Teff=5606K, logg=3.8, P=33.5days, Msini=6.5MJ V=9.4, Teff=5889K, logg=4.1, P=13.3days, Msini=1.0MJ V=8.4, P=109.4days, Msini=2.0MJ
Planet Candidates by MARVELS V=8.4, P=23.8days, Msini=2.9MJ V=11.6, Teff=4801K, logg=4.6, P=79.8days, Msini=4.0MJ V=11.3, Teff=5716K, logg=4.3, P=34.4days, Msini=27.0MJ V=9.2, Teff=4987K, logg=2.7, P=228.8days, Msini=12.5MJ
Summary • EXPERT delivers ~14% total detection efficiency from the telescope to the detector under typical seeing condition (1.5 arcsec at the KPNO 2.1m), operating in 0.39-0.7 um • Pressure control to within 2 mpsi over ~1 wk • Temperature control to within 10mK over ~1wk, goal to reach 2-4mK • RV drift within 50 m/s over a few days, goal to reach <10m/s long term goal • Reach ~1 m/s with iodine bracketing calibration for 1 hour integration, goal to reach 0.5 m/s with the ThAr or white light interferometer comb calibration over 0.39-0.7 um • Science operation with EXPERT in April 2010, with LiJET in September 2010, and more later • EXPERT direct echelle, covering 0.39-1.0 um with R=27,000, can reach ~3 m/s for mid-late M dwarfs for a J=7 M dwarf in 10 min planet survey with M dwarfs We acknowledge support from NSF, W.M. Keck Foundation, NASA, Sloan Foundation, SDSS-III program, DoD, NSFC, UCF-UF SRI, & UF