1. OGLE-2008-BLG-510: first automated real-time detection of a weak microlensing anomaly - brown dwarf or stellar binary?★
- Author
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Valerio Bozza, Allan Hornstrup, U. G. Joergensen, Timo Anguita, V. Batista, J. Janczak, S. Calchi Novati, C. C. Thoene, Y. C. Perrott, J.-Y. Choi, To. Saito, Luigi Mancini, M. Zub, Kailash C. Sahu, K. Wada, Philip Yock, Jean Surdej, K. Harpsoee, K. R. Pollard, J. A. R. Caldwell, In-Gu Shin, Joachim Wambsganss, S. H. Lee, A. Kniazev, K. Ulaczyk, M. Hundertmark, Fumio Abe, Y. Muraki, Yiannis Tsapras, R. A. Street, G. Masi, S. Dong, D. Kubas, D. M. Bramich, C. Liebig, R. W. Pogge, Radosław Poleski, L. Wyrzykowski, Ian A. Bond, Tobias C. Hinse, P. M. Kilmartin, John B. Hearnshaw, Eamonn Kerins, Y. Matsubara, Gaetano Scarpetta, D. Dominis Prester, L. Skuljan, Winston L. Sweatman, Akihiko Fukui, C.-U. Lee, Grzegorz Pietrzyński, K. Ohnishi, Kimiaki Masuda, Takahiro Nagayama, K. Furusawa, Igor Soszyński, Denis J. Sullivan, Andrew A. Cole, Martin Dominik, Yasuhiro Hashimoto, Sohrab Rahvar, Chang S. Han, S. R. Kane, A. V. Korpela, J. G. Greenhill, Iain A. Steele, Martin Burgdorf, N. Miyake, M. Mathiasen, C. Coutures, Takahiro Sumi, J. P. Beaulieu, Colin Snodgrass, P. J. Tristram, Nicholas J. Rattenbury, Amanda A. S. Gulbis, Petri Väisänen, M. Kubiak, Andrzej Udalski, R. M. Martin, Michał K. Szymański, S. Dieters, N. Kains, J. Donatowicz, K. H. Cook, Daisuke Suzuki, Arnaud Cassan, J. B. Marquette, Michael D. Albrow, Andrew Williams, David P. Bennett, Andrew Gould, Yoshitaka Itow, Per Kjaergaard, D. A. H. Buckley, Davide Ricci, John Southworth, J. W. Menzies, W. Lin, Alasdair Allan, Keith Horne, Darren L. DePoy, Shude Mao, P. Fouque, Seong-Hong Park, and C. H. Ling
- Subjects
Physics ,010504 meteorology & atmospheric sciences ,Event (relativity) ,Brown dwarf ,Binary number ,Astronomy and Astrophysics ,Astrophysics ,Parameter space ,Light curve ,Gravitational microlensing ,01 natural sciences ,Space and Planetary Science ,0103 physical sciences ,Orbital motion ,Anomaly (physics) ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
The microlensing event OGLE-2008-BLG-510 is characterised by an evident asymmetric shape of the peak, promptly detected by the ARTEMiS system in real time. The skewness of the light curve appears to be compatible both with binary-lens and binary-source models, including the possibility that the lens system consists of an M dwarf orbited by a brown dwarf. The detection of this microlensing anomaly and our analysis demonstrates that: 1) automated real-time detection of weak microlensing anomalies with immediate feedback is feasible, efficient, and sensitive, 2) rather common weak features intrinsically come with ambiguities that are not easily resolved from photometric light curves, 3) a modelling approach that finds all features of parameter space rather than just the `favourite model' is required, and 4) the data quality is most crucial, where systematics can be confused with real features, in particular small higher-order effects such as orbital motion signatures. It moreover becomes apparent that events with weak signatures are a silver mine for statistical studies, although not easy to exploit. Clues about the apparent paucity of both brown-dwarf companions and binary-source microlensing events might hide here.
- Published
- 2012