论文标题
来自各向同性的星爆星银河流出映射的各向同性星状星系流出的海洋乳流MG II发射
Circumgalactic Mg II Emission from an Isotropic Starburst Galaxy Outflow Mapped by KCWI
论文作者
论文摘要
我们从Z = 0.6942处的星形星系的Keck Cosmic Web成像器（KCWI）介绍了空间分辨的光谱法，该光谱显示了Mg II 2796，2803 Angstrom Doublet的发射，在边缘培养基中（CGM）在限制〜37 kpc的范围内显着（CGM）在37 kpc syly sylys sylys Prinative（1）中的发射（1）。 10^{ - 19} erg s^-1 cm^-2 arcsec^-2）。对观察进行反卷积后，我们获得了以7-spaxel（1.1 Arcsec^2）孔径测量的约31 kpc扩展的5个sigma检测。覆盖星系恒星区域的Spaxels显示出明显的P-Cygni样发射/吸收曲线，其蓝光吸收延伸至V = -800 km/s的相对速度延伸到相对速度；但是，p-Cygni轮廓让位于中央星系的大半径上的纯发射。我们进行了三维辐射转移模型，以推断流出气体的几何形状和速度和密度曲线。我们的观察结果与各向同性流出而非双开角phi <= 80摄氏度最一致。此外，我们的建模表明，必须降低半径的风速曲线对于重现大型圆形半径上MG II线发射曲线的速度宽度和强度。我们直接测量的MG II发射的程度通过我们的建模进一步证实，在该模型中，我们排除了范围<30 kpc的流出模型。
We present spatially-resolved spectroscopy from the Keck Cosmic Web Imager (KCWI) of a star-forming galaxy at z=0.6942, which shows emission from the Mg II 2796, 2803 Angstrom doublet in the circumgalactic medium (CGM) extending ~37 kpc at 3-sigma significance in individual spaxels (1-sigma detection limit 4.8 x 10^{-19} erg s^-1 cm^-2 arcsec^-2). After deconvolution with the seeing, we obtain 5-sigma detections extending for ~31 kpc measured in 7-spaxel (1.1 arcsec^2) apertures. Spaxels covering the galaxy stellar regions show clear P-Cygni-like emission/absorption profiles with the blueshifted absorption extending to relative velocities of v = -800 km/s; however, the P-Cygni profiles give way to pure emission at large radii from the central galaxy. We have performed three-dimensional radiative transfer modeling to infer the geometry and velocity and density profiles of the outflowing gas. Our observations are most consistent with an isotropic outflow rather than biconical wind models with half-opening angles phi <= 80 deg. Furthermore, our modeling suggests that a wind velocity profile that decreases with radius is necessary to reproduce the velocity widths and strengths of Mg II line emission profiles at large circumgalactic radii. The extent of the Mg II emission we measure directly is further corroborated by our modeling, where we rule out outflow models with extent <30 kpc.
