Tucana III 星流建模——与 LMC 的近距离交会
星系天体物理
2018-09-26 v1
摘要
我们展示了针对最近发现的 Tucana III 星流的首次动力学星流拟合结果。这些拟合假设固定的银河系势，并给出了自行预测，可通过即将发布的 Gaia 第二数据发布进行检验。这些拟合揭示 Tucana III 绕银河系处于偏心轨道，且更有趣的是，Tucana III 大约在 75 Myr 前曾经过大 Magellanic 云（LMC）15 kpc 范围内。鉴于此次近距离交会，我们在银河系和 LMC 共同存在的情况下拟合了 Tucana III 星流。我们发现预测的自行依赖于所假设的 LMC 质量，且 LMC 可诱发垂直于星流轨迹的显著自行。对此错位的探测将直接探查 LMC 对我们银河系影响的程度，并对几乎所有试图约束银河系势的方法具有重要意义。这样的测量将借助即将到来的 Gaia DR2 成为可能，从而实现对 LMC 质量的测量。
引用
@article{arxiv.1804.07762,
title = {Modelling the Tucana III stream - a close passage with the LMC},
author = {D. Erkal and T. S. Li and S. E. Koposov and V. Belokurov and E. Balbinot and K. Bechtol and B. Buncher and A. Drlica-Wagner and K. Kuehn and J. L. Marshall and C. E. Martinez-Vazquez and A. B. Pace and N. Shipp and J. D. Simon and K. M. Stringer and A. K. Vivas and R. H. Wechsler and B. Yanny and F. B. Abdalla and S. Allam and J. Annis and S. Avila and E. Bertin and D. Brooks and E. Buckley-Geer and D. L. Burke and A. Carnero Rosell and M. Carrasco Kind and J. Carretero and C. B. D'Andrea and L. N. da Costa and C. Davis and J. De Vicente and P. Doel and T. F. Eifler and A. E. Evrard and B. Flaugher and J. Frieman and J. García-Bellido and E. Gaztanaga and D. W. Gerdes and D. Gruen and R. A. Gruendl and J. Gschwend and G. Gutierrez and W. G. Hartley and D. L. Hollowood and K. Honscheid and D. J. James and E. Krause and M. A. G. Maia and M. March and F. Menanteau and R. Miquel and R. L. C. Ogando and A. A. Plazas and E. Sanchez and B. Santiago and V. Scarpine and R. Schindler and I. Sevilla-Noarbe and M. Smith and R. C. Smith and M. Soares-Santos and F. Sobreira and E. Suchyta and M. E. C. Swanson and G. Tarle and D. L. Tucker and A. R. Walker},
journal= {arXiv preprint arXiv:1804.07762},
year = {2018}
}
备注
13 pages, 8 figures, submitted to MNRAS. Comments welcome! See also Li et al. "The First Tidally Disrupted Ultra-Faint Dwarf Galaxy? -- Spectroscopic Analysis of the Tucana III Stream" on today's astro-ph