期刊
ASTROPHYSICAL JOURNAL
卷 802, 期 2, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/802/2/128
关键词
galaxies: formation; Galaxy: formation; Galaxy: halo; methods: analytical; methods: numerical; methods: statistical
资金
- NSF Office of Cyberinfrastructure [PHY-0941373]
- Michigan State University Institute for Cyber-Enabled Research (iCER)
- NSF grant Physics Frontiers Center/Joint Institute for Nuclear Astrophysics (JINA) [PHY 08-22648]
- Universidad Nacional de La Plata, Argentina
- Instituto de Astrofisica de La Plata, UNLP-Conicet, Argentina
- NASA through Hubble Fellowship [HST-HF-51284.01 A]
- Division Of Astronomical Sciences
- Direct For Mathematical & Physical Scien [1008342] Funding Source: National Science Foundation
Motivated by recent studies suggesting that the Large Magellanic Cloud (LMC) could be significantly more massive than previously thought, we explore whether the approximation of an inertial Galactocentric reference frame is still valid in the presence of such a massive LMC. We find that previous estimates of the LMC's orbital period and apocentric distance derived assuming a fixed Milky Way (MW) are significantly shortened for models where the MW is allowed to move freely in response to the gravitational pull of the LMC. Holding other parameters fixed, the fraction of models favoring first infall is reduced. Due to this interaction, the MW center of mass within the inner 50 kpc can be significantly displaced in phase-space in a very short period of time that ranges from 0.3 to 0.5 Gyr by as much as 30 kpc and 75 km s(-1). Furthermore, we show that the gravitational pull of the LMC and response of the MW are likely to significantly affect the orbit and phase space distribution of tidal debris from the Sagittarius dwarf galaxy (Sgr). Such effects are larger than previous estimates based on the torque of the LMC alone. As a result, Sgr deposits debris in regions of the sky that are not aligned with the present-day Sgr orbital plane. In addition, we find that properly accounting for the movement of the MW around its common center of mass with the LMC significantly modifies the angular distance between apocenters and tilts its orbital pole, alleviating tensions between previous models and observations. While these models are preliminary in nature, they highlight the central importance of accounting for the mutual gravitational interaction between the MW and LMC when modeling the kinematics of objects in the MW and Local Group.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据