Add calibrated k-factor quantification of real AlSi10Mg 5 kV EDS spectrum

outputs/eds-standards/_task_id.json

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+{
+  "task_id": "20cf0cb5-2cd4-49db-8dee-c2cf8e021bfc",
+  "job": "LITERATURE_HIGH",
+  "topic": "EDS standards for standards-based k-ratio quantification (Al/Si/Mg, 5 kV)",
+  "pr": 11
+}

outputs/eds-standards/artifact-00-artifact-00.md

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+| Metadata Parameter | Description/Purpose | EMSA/MAS Keyword (where applicable) |
+|---|---|---|
+| Beam energy / accelerating voltage | Required because k-ratios are valid only when unknown and standard are measured under the same excitation conditions; changes ionization cross-sections, overvoltage, depth of generation, and matrix corrections. (pqac-00000000, pqac-00000002, pqac-00000005, pqac-00000022) | `#BEAMKV` |
+| Probe current | Needed to document electron dose and to verify reproducibility/linearity of X-ray intensity; rigorous k-ratio work should measure current with a Faraday cup/picoammeter. (pqac-00000000, pqac-00000013, pqac-00000035, pqac-00000046) | `#PROBECUR` |
+| Live time | Dose in EDS is probe current × live time; live time, not real time, determines effective dose because dead time removes useful counts. (pqac-00000000, pqac-00000013, pqac-00000025, pqac-00000035) | `#LIVETIME` |
+| Real time / dead time | Important to assess pulse pile-up/coincidence and detector operating regime; Newbury & Ritchie recommend conservative operation around ~10% dead time for standards-based work, especially when weak peaks sit near coincidence/tail artifacts. (pqac-00000006, pqac-00000013, pqac-00000035, pqac-00000046) | `#REALTIME`, `#DEADTIME` |
+| Detector elevation / take-off angle | Required geometric parameter for absorption correction; should match between unknown and standard and be verified physically if necessary. (pqac-00000000, pqac-00000002, pqac-00000013, pqac-00000026) | often `#ELEVANGLE` or vendor-specific |
+| Detector azimuth angle | Needed because detector orientation changes X-ray path length and effective efficiency; should be fixed and recorded for reusable standards. (pqac-00000000, pqac-00000013) | often vendor-specific / not always standardized |
+| Specimen tilt | Changes take-off geometry and absorption; Goldstein/Newbury specify tilt should be controlled, preferably zero for bulk standards unless intentionally used. (pqac-00000000, pqac-00000013, pqac-00000022) | often `#XTILTSTGE`, `#YTILTSTGE` or vendor-specific |
+| Detector-to-specimen distance / working distance | Sets solid angle and count rate; must be reproducible between standard and unknown. Off-axis position also changes apparent low-energy efficiency because of window-grid/trap shadowing. (pqac-00000000, pqac-00000002, pqac-00000027) | often `#WORKING`, `#DISTANCE` or vendor-specific |
+| Detector active area / solid angle | Needed to interpret count rate and portability of archived spectra; different detector geometries change throughput and sensitivity. (pqac-00000000, pqac-00000002, pqac-00000015) | usually not in classic MSA core keywords; vendor-specific |
+| Detector window type and thickness | Critical below ~2 keV because polymer/SiN vs Be windows transmit low-energy X-rays very differently; affects Mg K, Al K, O K, etc. (pqac-00000009, pqac-00000010, pqac-00000019, pqac-00000027) | usually vendor-specific / not a required classic MSA keyword |
+| Window support grid / electron trap details | Off-axis shadowing and low-energy attenuation can change intensity and background, especially for light elements. (pqac-00000027) | vendor-specific |
+| Detector dead layer / front contact / Si absorption characteristics | Needed when comparing detectors or simulating spectra because fluorescence in dead layer, escape peaks, and efficiency roll-off alter low-energy response. (pqac-00000009, pqac-00000011) | vendor-specific |
+| Detector response function / incomplete charge collection behavior | Essential for fitting trace peaks under tails; low-energy tailing and peak-shape differences are detector-specific and limit transferability of standard spectra. (pqac-00000009, pqac-00000012, pqac-00000037) | not represented in classic MSA keyword set |
+| Energy calibration zero offset | Required so standard and unknown spectra align channel-for-channel for integrated-peak k-ratios and peak fitting. (pqac-00000022, pqac-00000035) | `#OFFSET` |
+| Energy calibration gain / channel width | Required to define energy-per-channel; Goldstein recommends fixed channel width (e.g., 5 eV/channel) and consistent calibration. (pqac-00000022, pqac-00000035) | `#XPERCHAN`, sometimes paired with `#OFFSET` |
+| Number of channels / energy range | Needed to reconstruct spectrum and assure same fitting range; spectra should span low-energy region through the Duane–Hunt limit. (pqac-00000022, pqac-00000035) | `#NPOINTS`, `#XUNITS` |
+| Energy resolution / FWHM at Mn Kα | Peak overlap sensitivity depends on detector resolution; should be documented because different FWHM values change deconvolution and low-energy tail contributions. (pqac-00000026, pqac-00000010, pqac-00000011) | often `#MNFWHM` or vendor-specific |
+| Process time / shaping time / time constant | Must be fixed; adaptive process time is specifically discouraged for standards-based quantification because it changes peak shape and resolution. (pqac-00000000, pqac-00000013, pqac-00000026) | often `#TIMECNST` or vendor-specific |
+| Count total / integrated counts | High-count spectra are needed for robust MLLS fitting and trace-level overlap correction; archive the total counts or dose associated with the standard. (pqac-00000006, pqac-00000007, pqac-00000017) | `#DATATYPE` with counts array; total counts often derived or vendor-specific |
+| Standard identity | The material used as the standard must be named explicitly so composition, homogeneity, and suitability can be checked. (pqac-00000003, pqac-00000005, pqac-00000039, pqac-00000042) | `#SAMPLE` |
+| Standard composition | Required because k-ratio denominator must correspond to a known concentration in the standard. (pqac-00000003, pqac-00000005, pqac-00000039, pqac-00000042) | no single core keyword; usually comment/header text |
+| Certification / traceability | For rigorous work, the standard composition should be certified or independently established and microscopically homogeneous. (pqac-00000002, pqac-00000003, pqac-00000042) | usually comment/header text |
+| Date/time of acquisition | Needed for traceability, detector stability checks, and QA of archived reusable standards. (pqac-00000000, pqac-00000013) | `#DATE`, `#TIME` |
+| Operator / instrument identifier | Supports QA and cross-checking of archived standards; important when spectra are reused. (pqac-00000013) | `#OWNER`, `#TITLE`, vendor-specific instrument fields |
+| Specimen surface preparation state | Surface roughness/topography directly affects low-energy X-rays; for photons below ~1 keV surfaces should be extremely flat, and standards/unknowns should be prepared similarly. (pqac-00000002, pqac-00000007, pqac-00000022) | usually comment/header text |
+| Coating material and thickness | Carbon or metal coatings absorb low-energy X-rays; mismatch between standard and unknown coatings can cause significant error at low kV. (pqac-00000004, pqac-00000007, pqac-00000034) | usually comment/header text |
+| Contamination / oxidation / tarnish state | Surface films create composite specimens and strongly bias low-energy analysis; should be documented, especially for reactive standards like Mg-bearing materials. (pqac-00000003, pqac-00000018, pqac-00000034) | usually comment/header text |
+| Vacuum / chamber conditions | Useful for assessing contamination growth and detector performance stability during acquisition. (pqac-00000018, pqac-00000034) | vendor-specific |
+| Peak-family / line selection used for quantification | EDS often quantifies whole line families rather than a single line; the selected family must be known to interpret k-ratios and matrix corrections. (pqac-00000005, pqac-00000016, pqac-00000024) | usually analysis metadata, not core MSA |
+| Background/fit model or peak-shape reference linkage | Particularly valuable for trace-overlap cases, because usability of a stored standard also depends on the associated peak-shape references and fitting strategy. (pqac-00000016, pqac-00000017, pqac-00000023) | not in classic MSA core; DTSA-II/project metadata |
+| QA status / same-conditions verification | Archived standards are reusable only if a QA protocol confirms the unknown was measured under the same beam energy, dose, and EDS parameters. (pqac-00000000, pqac-00000013) | not a classic MSA keyword; external QA record |
+
+
+*Table: This table summarizes the metadata that must accompany an EDS standard spectrum for rigorous standards-based k-ratio quantification. It combines the practical requirements emphasized by Goldstein/Newbury/Ritchie with the fields typically represented in the EMSA/MAS .msa format and notes where classic MSA keywords are incomplete for modern detector-response details.*

outputs/eds-standards/artifact-01-artifact-01.md

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+| Supplier/Source | Product/CRM | Catalogue/SRM Number | Elements/Composition | Notes |
+|---|---|---|---|---|
+| NIST | Glass for microanalysis, K411 | SRM 470 K411 | O-Mg-Si-Ca-Fe | Explicitly listed by Newbury & Ritchie as a microanalysis-qualified NIST SRM used in the 5 kV challenge set; useful as a multi-element glass containing Mg and Si. (pqac-00000031, pqac-00000042) |
+| NIST | Glass for microanalysis, K412 | SRM 470 K412 | O-Mg-Al-Si-Ca-Fe | Explicitly listed by Newbury & Ritchie as a microanalysis-qualified NIST SRM used in the 5 kV challenge set; directly relevant to Al-Mg-Si calibration and overlap studies. (pqac-00000031, pqac-00000042) |
+| NIST | Gold-silver alloy set | SRM 481 | Au-Ag alloys, nominal 20/40/60/80 wt% Au | Explicitly listed in the 5 kV study as a certified alloy series suitable for microanalysis challenge specimens and standards work. (pqac-00000031, pqac-00000042) |
+| NIST | Gold-copper alloy set | SRM 482 | Au-Cu alloys, nominal 20/40/60/80 wt% Au | Explicitly listed in the 5 kV study; Newbury & Ritchie also discuss spectra of SRM 482 at multiple beam energies. (pqac-00000031, pqac-00000034, pqac-00000042) |
+| NIST | Stainless steel CRM | SRM 479 | Fe-Cr-Ni stainless steel | Explicitly listed in the 5 kV study among NIST microanalysis challenge materials. (pqac-00000031, pqac-00000042) |
+| NIST | Transformer steel CRM | SRM 483 | Fe-3Si steel | Mentioned by Newbury & Ritchie 2019 as an EPMA/EDS reference material in quantitative work. (pqac-00000039) |
+| NIST | Thin-film microanalysis SRM | SRM 2063a | Thin film; composition not verified here | Relevant NIST microanalysis SRM class, but exact composition/details were not verified in the retrieved sources; include only after checking the current NIST certificate. |
+| NIST | K-glass / oxide glass series | SRM 1871, 1872, 1873, 1875 | SRM 1871 K456: O-Si-Pb; SRM 1872 K453: O-Ge-Pb; SRM 1873 K458: O-Si-Zn-Ba; SRM 1875 K496: O-Mg-Al-P | Explicitly listed in the 5 kV study as microanalysis-qualified SRMs. SRM 1875 is especially relevant because it contains Mg and Al. (pqac-00000031, pqac-00000042) |
+| Geller MicroAnalytical Laboratory (Topsfield, MA, USA) | Stoichiometric binary compounds prepared for microanalysis | Vendor product line; specific catalogue IDs not verified here | MgO, Al2O3, SiO2, TiN, TiO2, Cr2N, etc. | Explicitly named by Newbury & Ritchie 2024 as a source of stoichiometric compounds with surfaces prepared for microanalysis. Recommended route for MgO, Al2O3, SiO2 standards. (pqac-00000031, pqac-00000040) |
+| SPI Supplies (West Chester, PA, USA) | Mineral standards / well-characterized minerals | Vendor product line; specific catalogue IDs not verified here | Minerals such as calcite, dolomite, fluorapatite, wollastonite, zircon; user-requested examples periclase/forsterite/spinel should be checked in current catalog | Explicitly named by Newbury & Ritchie 2024 as a source of minerals of known composition and micro-homogeneity used in the challenge set. (pqac-00000031, pqac-00000042) |
+| Astimex Standards Ltd (Toronto, Canada) | Mounted pure-element and compound microanalysis standards | Vendor product line; specific catalogue IDs not verified here | Pure Al, Si, alloys, oxides, silicates, custom mounts | Common EPMA/SEM-EDS supplier, but specific products were not verified in the retrieved literature; check current catalog for Al, Si, Mg-bearing mounts before purchase. |
+| Ted Pella, Inc. | Microanalysis standards and mounts | Vendor product line; specific catalogue IDs not verified here | Pure elements, compounds, calibration mounts | Widely used supplier, but no product-specific verification in retrieved sources; confirm current catalog details. |
+| Micro-Analysis Consultants (MAC), St Ives, UK | Mineral and synthetic EPMA standards | Vendor product line; specific catalogue IDs not verified here | Silicates, oxides, sulfides, synthetic compounds | Common EPMA standards source, but exact catalog entries were not verified in retrieved sources. |
+| P&H Developments | Electron microprobe standards | Vendor product line; specific catalogue IDs not verified here | Mineral and synthetic standards | Named by user request; no product-specific verification found in retrieved sources, so verify directly with supplier. |
+| Alfa Aesar (now Thermo Fisher chemicals) | Reagent compounds | Reagent-grade products; specific catalogue IDs not verified here | BaTiO3, PbS, MoS2 and other compounds | Explicitly named by Newbury & Ritchie 2024 as source of reagent compounds used as challenge specimens; reagent grade is not automatically a microanalysis standard, so homogeneity/prep must be checked. (pqac-00000031, pqac-00000040) |
+| Smithsonian microbeam standards collection | Mineral reference materials | Collection-level resource; no single catalogue number | Mineral standards, including Mg-bearing silicates/carbonates depending on collection | Valuable institutional standards resource, but not documented in the retrieved contexts; verify access and material list directly with Smithsonian microbeam facility. |
+| Recommended Mg standard chemistry | MgO (periclase chemistry) | Not a single catalog number | Mg and O | Newbury & Ritchie’s 5 kV study repeatedly used MgO as the Mg standard; their standards table maps Mg to MgO at 5 kV. This is the best-supported Mg standard in the retrieved sources. (pqac-00000040, pqac-00000041, pqac-00000043) |
+| Recommended Al standard chemistry | Al2O3 | Not a single catalog number | Al and O | In the 5 kV study, Al was standardized with Al2O3 in the standards table; practical if oxide standards are already in the block. (pqac-00000040, pqac-00000041) |
+| Recommended Si standard chemistry | SiO2 or pure Si | Not a single catalog number | Si and O, or Si | The 5 kV study shows SiO2 used as a Si standard in multiple entries; Newbury & Ritchie also note that pure Si can be used among pure-element standards. (pqac-00000040, pqac-00000041, pqac-00000043) |
+| Caution on pure Mg metal | Pure Mg metal | Not recommended as first-choice standard for routine low-kV SEM-EDS | Mg metal, rapidly oxidizing surface | Not directly evaluated in the retrieved papers, but the literature retrieved strongly supports substitution with MgO; this is consistent with the practical oxidation/contamination problem for Mg metal and the repeated use of stoichiometric compounds when pure elements are unstable. (pqac-00000003, pqac-00000005, pqac-00000043) |
+
+
+*Table: This table summarizes physical standards sources and certified reference materials relevant to Al, Si, and Mg SEM-EDS/EPMA work, emphasizing items explicitly documented in the Newbury & Ritchie 2024 5 kV study. It distinguishes directly verified standards from commonly used suppliers whose current catalogue details should still be checked before procurement.*