论文标题
卷曲螺旋星系M63周围的新矮人
New dwarfs around the curly spiral galaxy M63
论文作者
论文摘要
我们提供了附近螺旋星系M 63（NGC 5055）的深（50小时暴露）图像，该图像用0.14米的光圈望远镜拍摄。星系光环展示了已知的非常微弱的恒星流系统，这些系统延伸到110 kpc。我们发现5个非常低的表面亮度矮人的矮化星系在m 63左右。假设它们是M 63的卫星，它们的中位参数为：绝对$ b $ -MAGNitude -8.8 mag，线性直径1.3 kpc，表面亮度$ \ sips Brightness $ \ sim $ 27.8 mag/sq/sq。 ARCSEC和线性预测分离93 kpc。基于四个具有测得的径向速度的较明亮的卫星，我们在$ \ sim $ 216 kpc上得出了M 63的低轨道质量估计为（5.1 $ \ pm $ 1.8）10 $^{11} m _ {\ odot} $。 M 63的特定特性是其旋转曲线的下降。考虑到M 63和附近三个大型星系NGC 2683，NGC 2903，NGC 2903，NGC 3521的旋转曲线的下降，我们认识到它们的低平均轨道质量与K波段亮度比（4.8 $ \ $ \ pm PM 1.1）银河系和M 31的相应比率。
We present a deep (50 hours exposed) image of the nearby spiral galaxy M 63 (NGC 5055), taken with a 0.14-m aperture telescope. The galaxy halo exhibits the known very faint system of stellar streams extending across 110 kpc. We found 5 very low-surface-brightness dwarf galaxies around M 63. Assuming they are satellites of M 63, their median parameters are: absolute $B$-magnitude -8.8 mag, linear diameter 1.3 kpc, surface brightness $\sim$ 27.8 mag/sq. arcsec and linear projected separation 93 kpc. Based on four brighter satellites with measured radial velocities, we derived a low orbital mass estimate of M 63 to be (5.1$\pm$1.8) 10$^{11} M_{\odot}$ on a scale of $\sim$216 kpc. The specific property of M 63 is its declining rotation curve. Taking into account the declining rotation curves of the M 63 and three nearby massive galaxies NGC 2683, NGC 2903, NGC 3521, we recognize their low mean orbital mass-to-K-band luminosity ratio, (4.8$\pm$1.1) $M_{\odot}/L_{\odot}$, that is only $\sim$1/6 of the corresponding ratio for the Milky Way and M 31.
