Metadata-Version: 2.4
Name: midas-xaf
Version: 0.1.0
Summary: Cross-Axis Faceted HEDM (XAF-HEDM): design + simulation toolkit for merged-reciprocal-space far-field HEDM through a six-faceted diamond anvil cell
Author-email: Hemant Sharma <hsharma@anl.gov>
License-Expression: BSD-3-Clause
Project-URL: Homepage, https://github.com/marinerhemant/MIDAS
Project-URL: Documentation, https://github.com/marinerhemant/MIDAS
Project-URL: Issues, https://github.com/marinerhemant/MIDAS/issues
Keywords: HEDM,3DXRD,diamond anvil cell,high pressure,differentiable physics,PyTorch,reciprocal space,Friedel pairs
Classifier: Development Status :: 3 - Alpha
Classifier: Intended Audience :: Science/Research
Classifier: Programming Language :: Python :: 3
Classifier: Operating System :: OS Independent
Classifier: Topic :: Scientific/Engineering :: Physics
Requires-Python: >=3.9
Description-Content-Type: text/markdown
License-File: LICENSE
Requires-Dist: numpy>=1.22
Requires-Dist: torch>=2.0
Requires-Dist: midas-diffract>=0.6.0
Requires-Dist: midas-hkls>=0.5.0
Requires-Dist: midas-stress>=0.8.0
Provides-Extra: dev
Requires-Dist: pytest>=7.0; extra == "dev"
Requires-Dist: pytest-cov; extra == "dev"
Provides-Extra: plot
Requires-Dist: matplotlib>=3.5; extra == "plot"
Dynamic: license-file

# midas-xaf — Cross-Axis Faceted HEDM (XAF-HEDM)

Design & simulation toolkit for a one-of-a-kind far-field HEDM measurement
performed through a **cubic diamond anvil cell** with a ~15° conical opening on
all six faces.

## The technique

- Narrow ω wedges (~16° wide) are collected at ω ≈ 0, ±90, 180° through the four
  **equatorial** faces in a given mounting.
- The cell is disassembled and **remounted about an orthogonal axis** (90° about
  the beam) so the previously top/bottom faces reach the equator — giving an
  orthogonal rotation axis in the crystal frame that **fills the first
  mounting's missing cone**.
- Two faces are measured in both mountings; embedded high-Z **fiducials** give an
  independent rigid-body remount registration.
- Both mountings are **merged into a single reciprocal-space reconstruction**.

## What the toolkit answers

Built on the differentiable `midas-diffract` forward model, it quantifies —
across energy / distance / detector / opening-angle / beam-mode / material knobs —
reciprocal-space coverage, spots per grain, Friedel-pair completeness, and above
all **strain determinability** (autograd Jacobian conditioning), including how it
degrades with the face opening angle (the 15° vs 20° v2-cell decision).

## Physics captured

- **Exit-aperture shadowing:** the diffracted beam must clear a face opening
  whose transmitting cone rotates with ω, so different detector sectors go dark
  at different ω (`exit_model="cone"`, the default).
- **Orthogonal-axis merge:** single-mounting vs merged strain determinability is
  compared directly (`metrics.cross_axis_gain`).

Status: **alpha** — Phase 1 (forward + metrics + sweep). Phase 2 (registration +
reconstruction) in progress. See `packages/XAF_HEDM_IMPLEMENTATION_PLAN.md`.
