tracers-and-profiles

name	tracers-and-profiles
description	Guides adding or modifying hmfast tracers and halo profiles. Use when editing src/hmfast/tracers/ or src/hmfast/halos/profiles/, or integrating new observables with HaloModel.

Tracers and profiles

New tracer

1. Subclass Tracer from tracers/base_tracer.py.
2. Set _required_profile_type to the correct HaloProfile subclass (pressure vs density vs matter, etc.).
3. Implement kernel(self, cosmology, z) with the same JAX/numpy conventions as sibling tracers.
4. Register the class in tracers/__init__.py and __all__.
5. Reuse _load_dndz_data / _normalize_dndz when working with n(z) files like existing galaxy tracers.

New or changed profile

1. Place implementations under halos/profiles/, inheriting from the appropriate base (HaloProfile, pressure, density, matter, HOD modules).
2. Export from halos/profiles/__init__.py if needed for clean imports.
3. Pair the profile with tracers that enforce the type via Tracer.profile.

Integration

• Follow existing files (tsz.py, galaxy_hod.py, cmb_lensing.py) for how Cosmology, data paths, and Const are used.

Tests

• Add focused tests under tests/ (kernels shapes, normalization, or finite outputs at reference z).