We present a three-dimensional model for the Milky Way fitted to the far-infrared (FIR) and near-infrared (NIR) data from the COBE/DIRBE instrument for Galactic latitudes |b| 30° and to within 20° of the Galactic center. Because of the low optical depth at 240 μm, the FIR emission traces the distribution of Galactic dust in the Galaxy. We model the dust distribution as due to three components: a warped exponential disk with scale length 0.28 R☉ and a flaring scale height, a spiral arm component with four arms as traced by Galactic H II regions, and the local (Orion) arm, which produces prominent emission features at Galactic longitudes l 80 and -100°. A cosmic infrared background of 1.07 MJy sr-1 is recovered, consistent with previous determinations. The dust distribution is then used to calculate absorption in J and K, and the stellar emission in these wavebands is modeled with two components: a warped exponential disk with a scale length of 0.28 R☉ and a spiral arm component dominated by two arms. This small scale length is consistent with a maximal disk model for our Galaxy, which is inconsistent with the cuspy dark matter halos predicted in CDM models. We find different amplitudes for the warp in the stars and dust, which starts within the solar circle.
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机译：我们为银河系提供了三维模型，该模型适用于银河纬度的COBE / DIRBE仪器的远红外（FIR）和近红外（NIR）数据| b | <30°，并且距银河系中心20°以内。由于240μm的低光学深度，FIR发射跟踪了银河中银河尘埃的分布。我们根据三个分量对粉尘分布进行建模：具有刻度长度为0.28R☉和呈喇叭形的标高的翘曲指数盘，由Galactic H II区域追踪的具有四个臂的螺旋臂分量以及局部（猎户座）臂，在银河经度l 80和-100°处产生明显的发射特征。回收了1.07 MJy sr-1的宇宙红外背景，与先前的测定一致。然后利用尘埃分布来计算J和K的吸收，并用两个分量模拟这些波段的恒星发射：标度长度为0.28R☉的弯曲指数盘和以两个臂为主的螺旋臂分量。这个小尺度的长度与我们银河的最大磁盘模型一致，这与CDM模型中预测的尖锐的暗物质光晕不一致。我们发现恒星和尘埃中的扭曲发生在太阳圈内不同的振幅。
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