Скачать презентацию Frequency of low-mass exoplanets what about the Скачать презентацию Frequency of low-mass exoplanets what about the

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Frequency of low-mass exoplanets. . what about the non -detections? SIMON O’TOOLE (AAO/HERTFORDSHIRE), CHRIS Frequency of low-mass exoplanets. . what about the non -detections? SIMON O’TOOLE (AAO/HERTFORDSHIRE), CHRIS TINNEY, JEREMY BAILEY, ROB WITTENMYER (UNSW), PAUL BUTLER (CARNEGIE), BRAD CARTER (SOUTHERN QUEENSLAND) Hugh Jones

Planet mass function Earth Neptune Jupiter Planet mass function Earth Neptune Jupiter

Exoplanet distributions Exoplanet distributions

AAPS (Anglo-Australian Planet Search) Nearly 300 nights over last 10 years on 250, V< AAPS (Anglo-Australian Planet Search) Nearly 300 nights over last 10 years on 250, V< 7. 7 F, G, K, M IV, V stars selected on Ca. HK and observed with S/N=200 has yielded more than 30 nearby exoplanets (and 18 spectroscopic binaries) Recent programme of operational upgrades Observing sequencer Automated iodine cell Exposure meter Near future – fibre feed

Many ‘noise’ components e. g. , asteroseismological signal Many ‘noise’ components e. g. , asteroseismological signal

asteroseismological signal function of L/M Based on Sun, Kjeldsen et al. 2008, Alpha Cen asteroseismological signal function of L/M Based on Sun, Kjeldsen et al. 2008, Alpha Cen A varies by ~20% plus ~10% over Solar cycle

Strategy continuous long blocks of telescope time Strategy continuous long blocks of telescope time

48 night run on 24 bright stars 48 night run on 24 bright stars

Exoplanets Exoplanets

Development of robust simulation system for AAPS data ¯ ¯ ¯ Use AAPS time Development of robust simulation system for AAPS data ¯ ¯ ¯ Use AAPS time stamps and internal errors Log 10 P = 0. 3, 0. 6, 0. 9, 1. 2 (or 2 to 20 days) e = 0. 0 -0. 2 in steps of 0. 1 Mass = 0. 02, 0. 05, 0. 1, 0. 2, 0. 5 MJ 7, 200 simulations/dataset ¯ Detectability criteria RMS (sim) < RMS (res) Km > 2 d. K + RMS (res) Pm > 2 d. P Chi 2 < 3 works for detections of HD 16417 and HD 4308

Differences between by star-by-star simulations Differences between by star-by-star simulations

Differences between by star-by-star simulations Differences between by star-by-star simulations

Detectability on 48 night run Detectability on 48 night run

Detectability sensitive to mass function 0. 01 -10 MJ lines of increasing thickness Detectability sensitive to mass function 0. 01 -10 MJ lines of increasing thickness

Mass function d. N/d. M ~M-1 (~17% of planets host planets with >3 ME Mass function d. N/d. M ~M-1 (~17% of planets host planets with >3 ME and <16 days)

Conclusions ¯ Simulation system can provide assessment of exoplanetary architectures based on RV data Conclusions ¯ Simulation system can provide assessment of exoplanetary architectures based on RV data ¯ With multiple telescopes and long campaigns (1 m/s precision) can constrain ¬Saturn mass planets out to 6 AU ¬Neptune mass planets out to 1 AU ¬Super-Earths out to 0. 3 AU ¬Earth-mass planets out to 0. 1 AU