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Progress of LiJET and transit search with Lijiang 2.4m telescope Jinming Bai (白金明) [email protected] Yunnan Observatory 2009-10-7 LiJET: Lijiang Exoplanet Tracker using Doppler dispersed fix-delay interferometer technique by: Florida University (Jian Ge’ group), USA Yunnan Observatory, CAS, China Nanjing University, China at: the 2.4m telescope in Lijiang The LiJET Project In late 2006, got supports from China and USA (1:1): NFSC, NSF, W.M. Keck Foundation, UCF-UF SRI program and UF In 2007, hardware and software design started, 4 young engineers from YNAO and USTC went to Florida University joining Jian Ge’s group In 2008, design finished, start producing Major Tasks and Schedule Schematic Layout for an ET Instrument Fringes Telescope Fibers HET Fiber Iodine Cell Dispersed Fringes Medium resolution spectrograph R=5000-10,000 Detector Erskine & Ge (2000), Ge et al. (2002), Ge (2002) Optical Design of RV Mode Prism 4kx4k CCD Slit Collimator-camera Output 1 Output 2 Fiber input Monolithic Interferometer Spectral resolution R~18,000 in 0.39-0.70 m Echelle Final Mechanical Layout of LiJET 4kx4k CCD camera Input fiber feed Prism Interferometer Collimator/camera Echelle A Monolithic Interferometer for LiJET Assembled interferometer •Field and thermal compensation •RV thermal drift ~ 0.5m/s/mK LiJET inside an Airtight Chamber in a Thermal Enclosure Thermal enclosure Vacuum chamber Air legs • The thermal enclosure dimension: 69" x 45" x 39.9“ • Thermal stability, ~1 mK over a short time and ~3mK over a long time Echelle spectrograph Assembled instrument in UF lab Vacuum Chamber Prism Collimator Thermal enclosure The LiJET Room in the dome of 2.4m Pipeline and Analysis Software Modifying existing developing FRANCIS FRinge Analysis Code for Interferometric Spectroscopy Statistical analysis Package Optimal scheduling Markov Chain Monte Calo (MCMC ) long-term velocity drifting correction Star parameter extraction LiJET Design Parameters Name RV Mode Fiber core diameter Fiber input focal ratio Image size on sky (arcsec) Fiber output focal ratio Collimator beam diameter Camera focal ratio Wavelength coverage Main disperser Cross-disperser Resolution elements Spectral resolution CCD detector 72 m f/4 1.55 f/4 80 mm f/4 390-700 nm 87 l/mm R2 echelle 45 degree PBM2Y prism 4.8 pixels 18,000 4kx4k with 15 m pixels LiJET design throughput Telescope 81%(primary and secondary) Fiber feed 60% Interferometer 66%(double output including lenses and folders) Slit 95% Collimator 94% (4 lenses and 6 surfaces) Echelle efficiency 75% Camera 85% (8 lenses, 14 surfaces) Total throughput 18% Photon limited RV precision of 15 min exposures with LiJET at Lijiang 2.4m telescope Magnitude RV precision V=6 0.4 m/s V=7 0.6 m/s V=8 1.0 m/s V=9 1.6 m/s V=10 2.5 m/s RV precision for different type stars and with different rotation velocity Peng, Fleming et al. 2009 Transiting planet candidates follow-up with LiJET Candidates are from: MARVELS (Multi-object APO Radial-Velocity Exoplanet Large-area Survey) SuperWASP (Super Wide Angle Search for Planets) YFOSC and Mosaic CCD camera transits search in open clusters at 2.4m telescope Main aim: To confirm planet detection and discover new planets To detect low mass (a few Earth masses) exoplanets around nearby planet-hosting bright stars with V<8 To find systems with more than one giant planets To determine planet parameters for planet candidates being ‘significantly’ detected in the MARVELS but not well determined orbit parameter Detect super-earth planets around bright stars constraining planet formation theory habitable planet search LiJET sensitivity for V<8 stars Signature of ice line and type I migration Schilaufman Ida & Lin 2009 Detection of Earth-like short period planets with intensive LiJET observations • 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 Summary The designed precision of LiJET is sub m/s, can discover earth-like planets and multiplanet system of bright stars Planet Candidates of LiJET are from MARVELS and SuperWASP to determine the orbit parameters of planets search multi-planet systems earth-like planets in late type stars Thank You!