高放大倍率引力微透镜事件 OGLE-2007-BLG-514 中恒星残骸的可能双星系统
地球与行星天体物理
2015-06-05 v1
摘要
我们报告了极高放大倍率 (A > 1000) 的双星微透镜事件 OGLE-2007-BLG-514。通过不同天文台的后续观测，我们获得了光变曲线中双峰结构周围的良好覆盖。包含视差效应（地球已知轨道运动）和透镜轨道运动的双透镜模型得出的双透镜质量比为 q = 0.321 +/- 0.007，以爱因斯坦半径为单位的投影分离为 s = 0.072 +/- 0.001。视差参数使我们能够确定透镜距离 D_L = 3.11 +/- 0.39 kpc 和总质量 M_L=1.40 +/- 0.18 M_sun；由此得出主成分和次成分的质量分别为 M_1 = 1.06 +/- 0.13 M_sun 和 M_2 = 0.34 +/- 0.04 M_sun。视差模型表明该双透镜系统可能由主序星构成。另一方面，我们使用贝叶斯分析估算了包含 xallarap 效应（源围绕伴星的可能轨道运动）和视差效应的模型的概率分布 (q = 0.270 +/- 0.005, s = 0.083 +/- 0.001)。双透镜的主成分质量相对较大，为 M_1 = 0.9_{-0.3}^{+4.6} M_sun，距离为 D_L = 2.6_{-0.9}^{+3.8} kpc。鉴于质量比测量的可靠性，伴星质量因此为 M_2 = 0.2_{-0.1}^{+1.2} M_sun。xallarap 模型暗示主透镜很可能是一个恒星残骸，如白矮星、中子星或黑洞。
引用
@article{arxiv.1207.1244,
title = {A possible binary system of a stellar remnant in the high magnification gravitational microlensing event OGLE-2007-BLG-514},
author = {N. Miyake and A. Udalski and T. Sumi and D. P. Bennett and S. Dong and R. A. Street and J. Greenhill and I. A. Bond and A. Gould and M. Kubiak and M. K. Szymanski and G. Pietrzynski and I. Soszynski and K. Ulaczyk and L. Wyrzykowski and F. Abe and A. Fukui and K. Furusawa and S. Holderness and Y. Itow and A. Korpela and C. H. Ling and K. Masuda and Y. Matsubara and Y. Muraki and T. Nagayama and K. Ohnishi and N. Rattenbury and To. Saito and T. Sako and D. J. Sullivan and W. L. Sweatman and P. J. Tristram and P. C. M. Yock and W. Allen and G. W. Christie and D. L. DePoy and B. S. Gaudi and C. Han and C. -U. Lee and J. McCormick and B. Monard and T. Natusch and B. -G. Park and R. W. Pogge and A. Allan and M. Bode and D. M. Bramich and N. Clay and M. Dominik and K. D. Horne and N. Kains and C. Mottram and C. Snodgrass and I. Steele and Y. Tsapras and M. D. Albrow and V. Batista and J. P. Beaulieu and S. Brillant and M. Burgdorf and J. A. R. Caldwell and A. Cassan and A. Cole and K. H. Cook and Ch. Coutures and S. Dieters and D. Dominis Prester and J. Donatowicz and P. Fouque and U. G. Jorgensen and S. Kane and D. Kubas and J. B. Marquette and R. Martin and J. Menzies and K. R. Pollard and K. C. Sahu and J. Wambsganss and A. Williams and M. Zub},
journal= {arXiv preprint arXiv:1207.1244},
year = {2015}
}
备注
31 pages, 6 figures, 7 tables, accepted in ApJ