仪器与数据

Instrument and data

eROSITA/eFEDS X-ray survey spectroscopy over约107.5 deg2；分析利用不同survey epochs检查SWCX，并联合建模热前景、CGM、CXB和吸收。

eROSITA/eFEDS X-ray survey spectroscopy over about 107.5 deg2, using different survey epochs to diagnose SWCX and jointly modeling thermal foregrounds, CGM, CXB, and absorption.

观测视线与样本域

Sightlines and sample domain

eFEDS位于约l=220-235 deg、b=20-40 deg的西侧天空，离M31超过105 deg。它是一个远方sky comparator，不是M31足迹测量或可局部化到M31的空间模型。

eFEDS lies in the western sky near l=220-235 deg and b=20-40 deg, more than 105 deg from M31. It is a distant-sky comparator, not an M31-footprint measurement or a spatial model localizable to M31.

原文测量量

Native measurement

Table 4给出best-fitting CGM component surface brightness：0.3-0.6、0.6-2.0和0.3-2.0 keV，单位1e-13 erg cm-2 s-1 deg-2。左右列分别是negligible/high SWCX固定模型。

Table 4 reports best-fitting CGM-component surface brightness in 0.3-0.6, 0.6-2.0, and 0.3-2.0 keV, in 1e-13 erg cm-2 s-1 deg-2. Left/right columns are fixed negligible/high SWCX models.

原文模型

Published model

模型包含unabsorbed Local Hot Bubble、吸收后的CGM thermal component、CXB和SWCX情景；neutral-column distribution用disnht。PDF/arXiv给出sigma=0.117，而publisher HTML Eq.1显示0.177；转换采用PDF/arXiv的0.117。

The model includes an unabsorbed Local Hot Bubble, absorbed CGM thermal component, CXB, and SWCX scenarios, with disnht for the neutral-column distribution. The PDF/arXiv give sigma=0.117 while publisher HTML Eq. 1 shows 0.177; the transfer follows the PDF/arXiv value 0.117.

原文结果

Published results

Table 4的CGM值为negligible/high SWCX：0.3-0.6 keV 24.1/15.6，0.6-2.0 keV 5.6/4.9。两列是系统情景，不是同一参数的置信区间。

Table 4 gives CGM values for negligible/high SWCX of 24.1/15.6 in 0.3-0.6 keV and 5.6/4.9 in 0.6-2.0 keV. The two columns are systematic scenarios, not a confidence interval on one parameter.

如何进入M31 Figure 3

Transfer into M31 Figure 3

对每个SWCX情景，用published kT/Z的Lodders APEC和lognormal-N_H quadrature计算F(0.5-0.6)/F(0.3-0.6)，乘Table 4 soft-bin flux后与published 0.6-2.0 flux相加，再换算deg2到arcmin2。得到high/negligible SWCX=0.291208/0.406510。这里没有M31几何transfer，只有common-band重建。

For each SWCX scenario, a Lodders APEC model at the published kT/Z plus lognormal-N_H quadrature gives F(0.5-0.6)/F(0.3-0.6). That fraction of the Table 4 soft-bin flux is added to the published 0.6-2.0 flux and deg2 is converted to arcmin2, yielding high/negligible SWCX values of 0.291208/0.406510. This is a common-band reconstruction, not an M31 geometry transfer.

假设与解释边界

Assumptions and boundaries

eFEDS与M31不共线；两个点的连接线只表示固定SWCX情景范围。Table 4没有把该值定义为M31方向的absorbed prior。

eFEDS is not co-directional with M31. The connector between its two points only groups fixed SWCX scenarios. Table 4 does not define an absorbed prior toward M31.

本论文对应的Figure 3数据点

Figure 3 points from this study

Primary-source证据地图

Primary-source evidence map

• publisher
• table4
• table2
• pdf
• arxiv