论文标题
使用快速无线电爆发来测量附近星系周围周围的环境气体
A measurement of circumgalactic gas around nearby galaxies using fast radio bursts
论文作者
论文摘要
所有类型的星系的环境培养基（CGM）中气体的分布受到限制。前景CGM为快速无线电爆发（FRB）的色散度量（DM）贡献了额外的贡献。我们使用chime/frb First Data Realesion（一种halo质量范围，以其他任何方式探测探测，我们对CGM的$ 10^{11} -10^{13} {13} \ M_ \ odot $ HALOS测量此DM多余。由于FRB的角度坐标的不确定性，仅对于附近星系而言，其本地化足以将它们与与任何前景光环相交。因此，我们堆叠在80 MPC之内的星系上，优化了堆叠方案，以近似堆栈的方差最小化并在FRB位置的不确定性上进行边缘化。该样品具有20-30 frb的相互作用的光晕，质量为$ 10^{11} -10^{12} \ m_ \ odot $，$ 10^{12} {12} -10^{13} \ m_ \ odot $，这些相互作用允许Marginal $ 1-2 \ 1-2 \，σ$ bass biss bins bins bins bins bins bins bins。 $ 10^{11} -10^{12} \ m_ \ odot $ halos bin还显示了1-2个病毒半径的DM多余。通过将数据与CGM气体概况的不同模型进行比较，我们发现所有模型都受到与无DM多余假设相比，数据最高为2- $σ$级别的数据。随着未来的Chime数据发布的2000-3000次突发，我们投射了CGM的4- $σ$检测。通过将FRB堆叠在一起，将可行的CGM模型区分开，将需要数万个爆发。
The distribution of gas in the circumgalactic medium (CGM) of galaxies of all types is poorly constrained. Foreground CGMs contribute an extra amount to the dispersion measure (DM) of fast radio bursts (FRB). We measure this DM excess for the CGMs of $10^{11}-10^{13}\ M_\odot$ halos using the CHIME/FRB first data release, a halo mass range that is challenging to probe in any other way. Because of the uncertainty in the FRBs' angular coordinates, only for nearby galaxies is the localization sufficient to confidently associate them with intersecting any foreground halo. Thus we stack on galaxies within 80 Mpc, optimizing the stacking scheme to approximately minimize the stack's variance and marginalize over uncertainties in FRB locations. The sample has 20-30 FRBs intersecting halos with masses of $10^{11}-10^{12}\ M_\odot$ and also of $10^{12}-10^{13}\ M_\odot$, and these intersections allow a marginal $1-2\,σ$ detection of the DM excess in both mass bins. The $10^{11}-10^{12}\ M_\odot$ halos bin also shows a DM excess at 1-2 virial radii. By comparing data with different models for the CGM gas profile, we find that all models are favored by the data up to 2-$σ$ level compared to the null hypothesis of no DM excess. With 2000-3000 more bursts from a future CHIME data release, we project a 4-$σ$ detection of the CGM. Distinguishing between viable CGM models by stacking FRBs with CHIME-like localization would require tens of thousands of bursts.
