DiffuseXrayCalibration：把 XMM 的弥漫辐射测量校准到可引用
DiffuseXrayCalibration: making XMM diffuse-emission measurements quotable
XMM-Newton 的 EPIC 相机看弥漫辐射时，隔着两种仪器自身的背景：准静态粒子背景（QPB）与软质子（SP）。本项目校准 ESAS 减数据 + Sherpa 拟合这条流水线，使同一天空区域在任何观测、任何离轴角、任何 SP/QPB 状态下给出同一个答案；做不到，就给出这个差异的测量值——系统误差预算。最显眼的症状是每个指向在拼接图边缘变亮（edge brightening）。为什么要做，见为什么存在一页。
XMM-Newton's EPIC cameras see diffuse emission through two backgrounds of the instrument's own making: the quiescent particle background (QPB) and soft protons (SP). This project calibrates the pipeline that removes them — ESAS reduction plus Sherpa fitting — so that one piece of sky gives the same answer in every observation, at every off-axis angle, and under every SP/QPB state; where it cannot, it delivers the measured difference itself: a systematic budget. The visible symptom is that every pointing brightens toward the edge of a mosaic (edge brightening). Why this matters is on the why the project exists page.
这一页回答四个问题：这是什么（本段）；现在到哪里了（目标表）；什么还没解决（未解决问题表）；下一步做什么（1–4 周计划与如何用手继续）。
This page answers four questions: what this is (this paragraph); where it stands (the objectives table); what is unsolved (the open-problems table); what to do next (the 1–4 week plan and how to continue by hand).
来源：Source: cognition-os/00_AI_BRIEFING.md, cognition-os/02_CURRENT_QUESTION.md
最新骨架：一条流水线，三个考题
Latest skeleton: one pipeline, three exam steps
来源：Source: cognition-os/02_CURRENT_QUESTION.md, MosaicSelfCal/BENCHMARK.md, cognition-os/tool_iteration.md
目标表：PI 的三步目标与基准测试目标
Objectives: the PI's three-step goal and the benchmark goals
| 目标Objective | 状态Status | 当前最佳数字Best current number | 趋势Trend |
|---|---|---|---|
| 第 1 步：抽谱（region + spectra）——高信噪比、低 SP、低未分辨点源/展源残差Step 1: regions and spectra — high S/N, low SP, low unresolved point/extended residual | 进行中in progress | CDFS P0：\(\tau/\bar{I}=0.246\)，\(\sigma/\bar{I}=0.245\)CDFS P0: \(\tau/\bar{I}=0.246\), \(\sigma/\bar{I}=0.245\) | → 掩膜规则已定（D012/D021），分数尚未收敛→ mask rule decided (D012/D021); score not yet converged |
| 第 2 步：拟合（fit sky 和 Src）——同一点指向内跨观测稳定；跨离轴角稳定Step 2: fit sky and Src — stable across observations of the same pointing, and across off-axis angle | 进行中in progress | M31 配对斜率（仅 QPB）：\(+1.51\pm0.16\ \%/\text{arcmin}\)M31 pair slope (QPB only): \(+1.51\pm0.16\ \%/\text{arcmin}\) | ↔ 取决于 SP 模板（flat \(-0.25\pm0.23\)，vignetted \(+2.47\pm0.23\)）↔ depends on the SP template (flat \(-0.25\pm0.23\), vignetted \(+2.47\pm0.23\)) |
| 第 3 步：成像（image，去掉 QPB 与 SP）——同指向叠加一致；不同指向拼接看不到 vignettingStep 3: images with QPB and SP removed — same-pointing stacks agree; mosaics show no visible vignetting | 未解决open | M31 平衡边缘步长（无 SP 扣除）：\(+9.9\pm2.0\ \%\)M31 balanced edge step (no SP subtraction): \(+9.9\pm2.0\ \%\) | ↔ 同一数据在四种 SP 假设下为 \(+0.1\) 到 \(+15.2\ \%\)↔ the same data gives \(+0.1\) to \(+15.2\ \%\) under four SP assumptions |
| 基准测试基线：同一固定天域跨 ObsID 的 \(\tau/\bar{I}\) 与离轴斜率（CDFS 与 M31）Benchmark baseline: between-ObsID \(\tau/\bar{I}\) and off-axis slope for one fixed sky cell (CDFS and M31) | 已建立established | CDFS P0：\(\tau/\bar{I}=0.246\)，斜率 \(+0.152/10'\)；M31 P0：\(\tau/\bar{I}=0.14\)，斜率 \(+0.25/10'\)CDFS P0: \(\tau/\bar{I}=0.246\), slope \(+0.152/10'\); M31 P0: \(\tau/\bar{I}=0.14\), slope \(+0.25/10'\) | → 这是待改进的基线，不是成果→ this is the baseline to improve, not a result |
| 考试集（exam v4 r240）：7 个 problem、18 个 ObsID、45 个 case 被减出来并审计Exam set (v4 r240): 7 problems, 18 ObsIDs, 45 cases reduced and audited | 完成done | 40 PASS，5 EXCLUDED，0 FAIL40 PASS, 5 EXCLUDED, 0 FAIL | → 冻结集（D020），后续分数都在它上面算→ frozen set (D020); every later score is computed on it |
来源：Source: MosaicSelfCal/BENCHMARK.md, cognition-os/02_CURRENT_QUESTION.md, MosaicSelfCal/results/cdfs_pipeline_comparison_v1.csv, MosaicSelfCal/results/exam_v4_r240/SUMMARY.md, cognition-os/tool_iteration.md 趋势箭头：→ 未收敛；↔ 两个估计矛盾；"持平"= 配对区间含 0。Trend arrows: → not converged; ↔ two estimates disagree; "No significant difference" = the paired interval contains 0.
未解决的问题
Open problems
| 问题Problem | 为何重要Why it matters | 当前最佳假设Best hypothesis | 下一个检验Next test | 负责人Owner | 状态Status |
|---|---|---|---|---|---|
| 边缘增亮（edge brightening）到底是 SP、QPB，还是仪器响应？Is edge brightening soft protons, the QPB, or the instrument response? | 这是 mosaics 里最显眼的失败，也是 PI 三步目标的第 3 步It is the most visible failure in mosaics and step 3 of the PI goal | 部分是 SP：用 ESAS 自己的 SP 模板后 M31 步长从 \(+9.5\ \%\) 降到 \(+6.7\ \%\)，但不归零Partly SP: with ESAS's own SP template the M31 step falls from \(+9.5\ \%\) to \(+6.7\ \%\), but not to zero | R20m：用晚期/早期 QPB 库重建 QPB 谱，重拟合并比较 MOS1/MOS2 比R20m: rebuild the QPB spectra from late-only vs early-only library rows, refit, compare the camera ratio | R20m | 检验中testing |
| SP 在探测器上的空间分布是什么形状？What is the spatial distribution of SP across the detector? | 拟合用的模型 \( \text{rsp\_flat}(A_{\text{sky}}\cdot\text{SP}) \) 默认 SP 在探测器上是均匀的；如果不是，所有 SP 扣除都带系统误差The fit model \( \text{rsp\_flat}(A_{\text{sky}}\cdot\text{SP}) \) assumes SP is uniform across the detector; if it is not, every SP subtraction carries a systematic | 硬带（2-5 keV）里 ESAS 的 det 图最符合（原始 SP 计数每像素从 \(2'-6'\) 到 \(12'-14'\) 下降 \(0.88\pm0.13\)，ESAS 图 0.76，均匀 1.00，光子 vignetting 0.44）In the hard band (2-5 keV) the ESAS detector map fits best (raw SP counts per pixel fall \(0.88\pm0.13\) from \(2'-6'\) to \(12'-14'\); ESAS map 0.76, flat 1.00, photon vignetting 0.44) | 软带（0.4-1.25 keV，边缘增亮所在的带）目前测不到；需要在同一指向内用 SP 时间变化做示踪The soft band (0.4-1.25 keV, where the edge brightening lives) is not yet measurable; needs a time tracer of SP inside one pointing | R18b2 / R20 | 未解决open |
| MOS1/MOS2 的 SP 归一比在 2012 年发生台阶（\(0.68\to1.47\)），原因是什么？The MOS1/MOS2 SP-normalisation ratio steps in 2012 (\(0.68\to1.47\)); what causes it? | 任何跨 2012-12 合并 SP 先验或比较都是错的；这也决定了 SP 扣除能否跨年代使用Any SP prior or comparison pooled across 2012-12 is wrong, and it decides whether an SP subtraction can be used across epochs | 台阶与 MOS1 CCD3 丢失（2012-12-11）完全退化，也与 QPB 模板年代（库在 2012-01 结束）退化；面积效应已被排除The step is perfectly degenerate with the MOS1 CCD3 loss (2012-12-11) and with the QPB-template epoch (library ends 2012-01); the area effect is refuted | RT-M75 + R20m 的 sky-unlinked 臂：把两台相机的天空模型解开后台阶是否还在RT-M75 plus R20m's sky-unlinked arm: does the step survive with the sky unlinked between cameras | RT-M75 / R20m | 检验中testing |
| 重复指向能否测出 SP 的绝对水平？Can repeat pointings measure the absolute SP level? | SP 水平是第 3 步成像的关键输入；测不出来就无法给 SP 扣除定标The SP level is the key input to step 3; without it the SP subtraction cannot be normalised | 不能：最好的重复对（0784000101/0201，相距 \(0.04'\)）只是上限，不是零；测量受 QPB 协方差限制，不受计数限制No: the best repeat pair (0784000101/0201, \(0.04'\) apart) is an upper limit, not a null; the test is limited by the QPB covariance, not by counts | R20d/R20e：测出观测间的 QPB 协方差，再重拟这 8 个相机对R20d/R20e: measure the between-epoch QPB covariance, then refit the 8 camera pairs | R20d / R20e | 未解决open |
| pn 相机的 QPB 为什么被高估？Why is the pn camera's QPB over-normalised? | pn 目前只能做交叉检查（T01）；修不好就不能升级为主要相机pn is a cross-check only (T01); until it is fixed it cannot be promoted | 不是角区光子泄漏（OOT 只占 \(2.5\ \%\)，边缘 \(0.5\ \%\)）；更像 FWC 模板迁移，最佳修正是 FoV 12-14 keV 归一化Not corner photon leakage (OOT \(2.5\ \%\), edge \(0.5\ \%\)); likelier an FWC template transfer, best corrected by the FoV 12-14 keV normalisation | R5b：pn 减数据 + pn/MOS 联合拟合，held-out 检验 pn QPB 标度R5b: pn reduction plus joint pn/MOS fits, with a held-out test of the pn QPB scale | R5b | 检验中testing |
| 暗天区里 SP 与天空的简并如何打破？How is the SP-sky degeneracy broken in faint fields? | WCDFS 是最暗的检验场；在那里谱拟合给出的 SP 归一不可靠，成像又过度扣除WCDFS is the faintest testbed; there the spectral SP norm is unreliable and the image over-subtracts | 分组方式本身就是一个系统误差（G1 把 2-12 keV 打进一个 bin，天空差 \(18\ \%\)）；用 G2 式边界The grouping choice is itself a systematic (G1 packs 2-12 keV into one bin, moving the sky by \(18\ \%\)); use G2-style boundaries | R3c：联合似然比检验（天空共享 vs 每观测自由，SP 每观测自由）R3c: joint likelihood-ratio test (sky shared vs free per observation, SP free per observation) | R3c | 部分完成partly done |
| SAS 22.1 后端能否用于生产？Can the SAS 22.1 backend be used for production? | SAS 20 与 22.1 的 ARF 差 \(+7\) 到 \(+22\ \%\)；用错后端会让所有天空水平偏移The SAS 20 and 22.1 ARFs differ by \(+7\) to \(+22\ \%\); the wrong backend shifts every sky level | 差异可归因：ARF 来自 arfgen 开关，QPB 来自 FWC 来源 + MOS1 自建角区；但 pn 端到端与可复现性声明还没过The differences are attributable (ARF from arfgen switches, QPB from the FWC source plus MOS1's own corner), but pn end-to-end and the reproducibility statement have not passed | R15 / esas v1.8.0：pn 端到端、ANOMFL、可复现性声明，然后 PI 签字R15 / esas v1.8.0: pn end to end, ANOMFL, a reproducibility statement, then PI sign-off | R15 | 检验中testing |
来源：Source: cognition-os/REDTEAM_QUEUE.md, MosaicSelfCal/RESEARCH_PLAN.md, cognition-os/08_RUNNING.md
未来 1–4 周
The next 1–4 weeks
计划顺序照 MosaicSelfCal/RESEARCH_PLAN.md 的 SP 路线图（PI 2026-10-17）与 cognition-os/08_RUNNING.md §7 的建议方向。每条后面是它要回答的问题。
The order follows the SP roadmap in MosaicSelfCal/RESEARCH_PLAN.md (PI 2026-10-17) and the proposed directions in cognition-os/08_RUNNING.md §7. Each item names the question it answers.
| 时间When | 做什么What | 回答什么问题Question answered | 状态State |
|---|---|---|---|
| 现在进行in flight | R20m QPB 库年代检验；RT-M75 天空解锁；RT-M74 SAS22 ARF 归因R20m QPB library-epoch test; RT-M75 sky-unlinked; RT-M74 SAS22 ARF attribution | 2012 年台阶是 QPB 模板、CCD3 丢失，还是天空模型把两台相机绑在一起造成Is the 2012 step the QPB template, the CCD3 loss, or an artefact of the sky model linking the two cameras | 运行中running |
| 接下来next | R20 家族收尾：把 SP 水平、QPB 协方差、SP 空间模板三者合并成一个每观测的 SP 产品Close the R20 family: merge the SP level, the QPB covariance and the SP spatial template into one per-observation SP product | 边缘增亮中有多少是 SP，多少留给 QPB 与仪器How much of the edge brightening is SP, and how much is left for QPB and the instrument | 待定pending |
| 并行in parallel | R5b pn 减数据与联合拟合；R15 / esas v1.8.0 READY 门R5b pn reduction and joint fits; the R15 / esas v1.8.0 READY gate | pn 能否成为第二台主相机；SAS 22.1 能否用于生产Can pn become a second primary camera; can SAS 22.1 be used for production | 运行中running |
| 2–4 周2–4 weeks | 工具发布：edgestep 包、xsherpa SP 响应、esas SP 成像模板；然后 DXC 用固定版本重测Tool releases: the edgestep package, the xsherpa SP response, the ESAS SP image template; then a DXC re-test pinned to the version | 修正能否落到工具里并被独立复现Whether the fixes land in the tools and are independently reproduced | 待定pending |
| 验收标准acceptance | 高 SP / 低 SP 时间桶给同一面亮度；M31/LMC/WCDFS 配对斜率归零；mosaic 看不到 vignettingHigh- and low-SP time bins of one pointing give the same surface brightness; M31/LMC/WCDFS pair slopes zero; mosaics show no visible vignetting | PI 三步目标是否达成Whether the PI's three-step goal is met | 未达成not met |
来源：Source: MosaicSelfCal/RESEARCH_PLAN.md, cognition-os/08_RUNNING.md, cognition-os/tool_iteration.md
本次更新 / 数据截至
What's new / Data as of
本次更新What's new
2026-10-19：手册首次建立（H-DXC-1）。这是 DiffuseXrayCalibration 的第一本手册，从零写起：为什么做、物理与统计、历史、当前设计、当前状态、如何用手继续、术语表与阅读清单，外加论文草稿与讨论班幻灯片。
2026-10-19: the handbook is built for the first time (H-DXC-1).This is the first DiffuseXrayCalibration handbook, written from scratch: why the project exists, the physics and statistics, the history, the current design, the current state, how to continue by hand, a glossary and reading list, plus a paper draft and a seminar deck.
本页所有数字取自下方列出的记录文件；没有一项是本手册自己算出来的。
Every number on this page is read from the record files listed below; none is computed by this handbook.
数据截至Data as of
项目状态：2026-10-19 06:35 EDT（cognition-os/08_RUNNING.md revision 1）。
Project state: 2026-10-19 06:35 EDT (cognition-os/08_RUNNING.md revision 1).
本手册读到的最新科学记录：2026-10-19 02:20 UTC（R20j 的 REPORT.sol.md，0763120101/0201 MOS2 差值是 \(1.2\sigma\)–\(1.9\sigma\)，没有合格检测）。
The newest science record this handbook read: 2026-10-19 02:20 UTC (R20j's REPORT.sol.md: the 0763120101/0201 MOS2 difference is \(1.2\sigma\)–\(1.9\sigma\), with no qualified detection).
更晚的记录（评审、决定、新结果）以它们为准；本页在下次刷新时更新。
Later records (reviews, decisions, new results) take precedence; this page is updated at the next refresh.