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arXiv 1504.06324astro-ph.GAhep-exhep-ph
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Milky Way中暗物质分布的动力学约束

Dynamical constraints on the dark matter distribution in the Milky Way

Miguel Pato, Fabio Iocco, Gianfranco Bertone

摘要:

准确了解银河系中暗物质的分布对于研究星系形成和寻找粒子暗物质具有重要意义。在本文中,我们设置新的动力学约束银河系暗物质配置文件通过比较观察到的旋转曲线,更新与全面汇编的运动示踪剂,推断出从一个广泛的基于观测的形态的凸起,光盘和气体。广义Navarro-Frenk-White(NFW)和Einasto暗物质配置文件的数据进行拟合,以确定本地密度,斜率和尺度半径的有利范围。对于一个典型的重子模型,典型的局部圆速度为230 km/s,太阳到银河系中心的距离为8 kpc,我们发现局部暗物质密度为0.420+0.021-0.018(2 sigma)+- 0.025 GeV/cm ^3(0.420+0.019-0.021(2 sigma)+- 0.026 GeV/cm^3),其中第二个误差是由重子模型引起的系统性估计。除了银河系参数之外,太阳圈内外不确定性的主要来源分别是重子模型和旋转曲线测量。未来几年,即将进行的天文观测预计将大大减少所有这些不确定性。

英文摘要:

An accurate knowledge of the dark matter distribution in the Milky Way is of crucial importance for galaxy formation studies and current searches for particle dark matter. In this paper we set new dynamical constraints on the Galactic dark matter profile by comparing the observed rotation curve, updated with a comprehensive compilation of kinematic tracers, with that inferred from a wide range of observation-based morphologies of the bulge, disc and gas. The generalised Navarro-Frenk-White (NFW) and Einasto dark matter profiles are fitted to the data in order to determine the favoured ranges of local density, slope and scale radius. For a representative baryonic model, a typical local circular velocity of 230 km/s and a distance of the Sun to the Galactic centre of 8 kpc, we find a local dark matter density of 0.420+0.021-0.018 (2 sigma) +- 0.025 GeV/cm^3 (0.420+0.019-0.021 (2 sigma) +- 0.026 GeV/cm^3) for NFW (Einasto), where the second error is an estimate of the systematic due to baryonic modelling. Apart from the Galactic parameters, the main sources of uncertainty inside and outside the solar circle are baryonic modelling and rotation curve measurements, respectively. Upcoming astronomical observations are expected to reduce all these uncertainties substantially over the coming years.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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