تقرير
Spectroscopic Characterisation of Microlensing Events: Towards a New Interpretation of OGLE-2011-BLG-0417
| العنوان: | Spectroscopic Characterisation of Microlensing Events: Towards a New Interpretation of OGLE-2011-BLG-0417 |
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| المؤلفون: | Santerne, A, Beaulieu, J.-P, Rojas Ayala, B, Boisse, I, Schlawin, E, Almenara, J.-M, Batista, V, Bennett, D, Diaz, R. F, Figueira, P, James, D. J, Herter, T, Lillo-Box, J, Marquette, J. B, Ranc, C, Santos, N. C, Sousa, S. G |
| المصدر: | Astronomy & Astrophysics. 595(8) |
| بيانات النشر: | United States: NASA Center for Aerospace Information (CASI), 2016. |
| سنة النشر: | 2016 |
| مصطلحات موضوعية: | Astrophysics |
| الوصف: | The microlensing event OGLE-2011-BLG-0417 is an exceptionally bright lens binary that was predicted to present radial velocity variation at the level of several km s1. Pioneer radial velocity follow-up observations with the UVES spectrograph at the ESOVLT of this system clearly ruled out the large radial velocity variation, leaving a discrepancy between the observation and the prediction. In this paper, we further characterise the microlensing system by analysing its spectral energy distribution (SED) derived using the UVES spectrum and new observations with the ARCoIRIS (CTIO) near-infrared spectrograph and the Keck adaptive optics instrumentNIRC2 in the J, H, and Ks-bands. We determine the mass and distance of the stars independently from the microlensing modelling. We find that the SED is compatible with a giant star in the Galactic bulge and a foreground star with a mass of 0.94 +/- 0.09 M solar mass at a distance of 1.07 +/- 0.24 kpc. We find that this foreground star is likely the lens. Its parameters are not compatible with the onespreviously reported in the literature (0.52 +/- 0.04 M solar mass at 0.95 +/- 0.06 kpc), based on the microlensing light curve. A thoughtful reanalysis of the microlensing event is mandatory to fully understand the reason of this new discrepancy. More importantly, this paper demonstrates that spectroscopic follow-up observations of microlensing events are possible and provide independent constraints on the parameters of the lens and source stars, hence breaking some degeneracies in the analysis. UV-to-NIR low-resolution spectrographs like X-shooter (ESOVLT) could substantially contribute to this follow-up efforts, with magnitude limits above all microlensing events detected so far. |
| نوع الوثيقة: | Report |
| اللغة: | English |
| تدمد: | 1432-0746 0004-6361 |
| DOI: | 10.1051/0004-6361/201527710 |
| الوصول الحر: | https://ntrs.nasa.gov/citations/20170011300Test |
| ملاحظات: | NNG17PT01A |
| رقم الانضمام: | edsnas.20170011300 |
| قاعدة البيانات: | NASA Technical Reports |
Full Text Finder | تدمد: | 14320746 00046361 |
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| DOI: | 10.1051/0004-6361/201527710 |