Transcript Slide 1
Searching for low mass extra solar planets via microlensing. Jean-Philippe Beaulieu, Virginie Batista, Arnaud Cassan, Christian Coutures, Jadzia Donatowicz, Pascal Fouqué, Daniel Kubas, Jean-Baptiste Marquette, Olivier Mousis, et al. (PLANET/RoboNET, HOLMES) Europlanet, Potsdam Target Field in the Central Galactic Bulge Galactic center 8 kpc Sun 1-7 kpc from Sun Light curve Source star and images Lens star and planet Observer A planetary companion tE 20 d, M 0.3 M sun : tp q tE Jupiter: q 3 10-3 t p 1 d T erre: q 105 tp 1.5 h Hunting for planets via microlensing Detecting real time microlensing event : OGLE-III and MOA 2 Detecting anomalies real time : Networks of telescopes to do 24 hours monitoring : PLANET/RoboNET, microFUN Accurate photometry (Image subtraction since 2006) Real time analysis and modeling OGLE-III has an online anomaly detector (EWS) MOA-II Selecting microlensing event with good planet detection efficiency Two schools : - Mainly high magnification events and alerted anomalies (microFUN) - Monitoring a larger number of events (PLANET/ROBONET) . data, models, are shared immediately among the microlensing community. All Cooperation is the way to go ! PLANET collaboration : Probing Lensing Anomaly NETwork (current members) http://planet.iap.fr Boyden 1.5m M. D. Albrow, J.P. Beaulieu, D. Bennett, D. Bramich, S. Brillant, J. A. R. Caldwell, H. Calitz, A Cassan, K. Cook, C. Coutures, M. Dominik, J. Donatowicz, D. Dominis, P. Fouqué, J. Greenhill, K. Hill, M. Hoffman, K. Horne, U. Jorgensen, S. Kane, D. Kubas, R. Martin, J. Menzies, P. Meintjes, K. R. Pollard, K. C. Sahu, Y. Tsapras,J. Wambsganss, A. Williams, M. Zub Institut d'Astrophysique de Paris, INSU CNRS, Paris, France Univ. of Canterbury, Dept. of Physics & Astronomy, Christchurch, New Zealand South African Astronomical Observatory, South Africa Boyden Observatory, Bloemfountein, South Africa Canopus observatory, Univ. of Tasmania, Hobart, Australia Niels Bohr Institute, Copenhagen, Denmark Univ. of Potsdam, Potsdam, Germany Space Telescope Science Institute, Baltimore, U.S.A. Perth Observatory, Perth, Australia PLANET/RoboNet SITES Boyden 1.5m ESO Danish 1.54m 2003-2008 Sutherland, SAAO 1m 2002+ Boyden, 1.5m, CCD 2006, 2007 Perth 0.6m 2002-2007+ Hobart 1m, 2002-2007+ Brazil 0.6m, 2007+ Robonet : Liverpool 2m, Canary 2005+ Faulkes North 2m, Hawaii 2006+ Faulkes South 2m, Australia 2007+ Goals at each site : - 1 % photometry, - Adapted Sampling rate - Online analysis. OBSERVING STRATEGY, DECISION TAKING Homebase checks : - OGLE, MOA alert pages - results from Bayesian PSPL fits to OGLE data (Albrow) - results from K.Horne priority pages - data collected by PLANET/RoboNet and current fits He can ask for data to be re-reduced to double check anomalies. Then he decides an observing strategy, sampling rates for different events He issues anomaly alerts to the community. Homebase should be on the deck 24 hours a day for 2-3 weeks Real time analysis system In Out Data from all site uploaded to Paris every 5 min http://planet.iap.fr RoboNet SAAO Boyden Chile Data stored in Paris Models updated Prediction of future behavior Alert if anomalies Brasil Hobart Perth OGLE-2005-BLG-390 OGLE-2005-BLG-390 Coopération : PLANET/RoboNET, OGLE-III, MOA-II AT LAST, A TEXT BOOK MICROLENSING EVENT Gould Loeb 1992, Bennett & Rhie 1996, … Data in the anomaly from : PLANET-Danish, OGLE, MOA-II, PLANET-Perth Data outside the anomaly from : PLANET/Robonet, PLANET-Hobart PROBABILITY DENSITIES OF THE STAR AND ITS PLANET A companion to this frozen super Earth ? Excluding at : 50 % Jupiter over 1.1-2.3 AU 70 % 3 Jupiter over 1.5-2.2 AU Kubas et al., 2007 submitted Core accretion models by Idal & Lin OGLE-2005-BLG-169Lb : a weak Neptune planet signal Gould et al. 2006, MicroFUN, OGLE, RoboNet A new Jovian analogue in a resonnant caustic system 45 5 microlensing planets, their time scale. KB-07-197 Do gas giants prefer host stars that cause longer events ? Ie more massive ones ? Current status of microlensing planet hunting PLANET/Robonet/HOLMES (network of 9 telescopes). Now – 200? MicroFUN Now-200? OGLE III and MOA-2 - Constraints on Jupiters and low mass planets (down to few Earth mass) - Monitoring of high mag events - Monitoring of any mag events (PLANET/RoboNet, OGLE) Las cumbres plans ? A 1m observing in J from Antartica ? Network of wide field imager Earth Hunter + OGLE-IV + MOA-2 2011+ ? Statistics on Cool Earth mass planets, possibly habitable zone. NASA mission MPF ( PI Bennett) to be re-submitted ? ESA DUNE mission (cosmic shear + planet search ) Abundance of planets in habitable zone. MPF : 36 months, 200 million stars, 4 fields of 0.66 sq2, FWHM=0.25 arcsec ~100 q Earth, ~6000 q Jupiter (q fraction of stars with planets), Mars detectable CONCLUSION Microlensing is probing “Frozen” planets. 5 microlensing planets for 3 scenarios : •2 Strong caustic •2 High mag central caustic • 1 Planetary caustic 3 ~Jupiters, 1 ~5.5 Earth, 1 ~13 Earth (Probability of detecting Jupiters is ~50 times larger) Giant planets are rare, suggests 1-15 MEARTH might be common Giant planets in events with large tE (more massive stars) Several planets in “stock”… modeling underway. ~Earth mass planets on ~AU orbits to be discovered soon…