Source: https://guthlabs.ai/docs/instruments/hr-diagram-plotter/

instrument / verified-clean

# HR Diagram Plotter

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Inspectable records

[01**Overview**Purpose and lifecycle](<https://guthlabs.ai/docs/instruments/hr-diagram-plotter/>)[02**Mechanism**Method and assumptions](<https://guthlabs.ai/docs/instruments/hr-diagram-plotter/mechanism/>)[03**Implementation**Binding and validation](<https://guthlabs.ai/docs/instruments/hr-diagram-plotter/implementation/>)[04**Qualification**Evidence and errata](<https://guthlabs.ai/docs/instruments/hr-diagram-plotter/qualification/>)

## Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

**Area**: Earth & Space (astronomy, orbital mechanics, meteorology, geology, geodesy, oceanography)

**Tranche**: tranche-6

**Evidence ID**: t6-020

**Ledger rows**: 1

No ledger note is attached.

## Review findings

The honest-label warning is appropriate, but the instrument cannot be formula-verified or deterministically classified until the axis transformations, solar constants, reference table, interpolation, main-sequence-band definition, and giant/dwarf zone boundaries are specified. The four vectors verify coordinate handling and standard HR-diagram conventions under explicit assumptions, not the unspecified classification overlay.

### Formula and scope findings

- The specification does not define a numerical plotting formula: it is unclear whether luminosity is plotted as L, L/L_sun, or log10(L/L_sun).

- The main-sequence band overlay is unspecified; no reference-table values, interpolation method, band width, or uncertainty is provided, so its placement cannot be independently verified.

- The giant and dwarf classification zones have no numerical boundaries or classification algorithm.

- For (B-V, Mv) inputs, no color-temperature relation, magnitude-luminosity relation, or zone thresholds are specified.

- The axis conventions are ambiguous. A conventional HR diagram reverses the Teff axis and usually reverses the absolute-magnitude axis, but this is not stated.

- The use of 'CODATA solar values' is insufficiently specific because the exact adopted solar luminosity and effective temperature are not given.

### Unit assumptions

- For Teff inputs, temperatures are assumed to be effective temperatures in kelvin, not degrees Celsius or Fahrenheit.

- For the L-based vectors below, luminosity is assumed to be expressed in solar luminosities (L/L_sun), with a linear plotted y-coordinate unless otherwise stated.

- If luminosity is supplied in watts, the conversion assumption is L_sun = 3.828e26 W; the specification does not state whether this conversion is required.

- For color-magnitude inputs, B-V is dimensionless and Mv is absolute visual magnitude in magnitudes; apparent magnitude must not be accepted as Mv.

- A conventional HR display is assumed to place hotter Teff values to the left and brighter/lower Mv values higher on the display, although the specification does not require this.

## Boundary hardening

**BREAK_CLAIMED** · SELF_FLAGGED

The zero-luminosity input produces an undefined logarithm and must be rejected. Additional hazards remain because the specification does not define an explicit input-mode discriminator, the main-sequence/giant/dwarf zone boundaries, or the exact axis-direction implementation.

## Errata and corrections

No applied erratum is attached to this unique-name record.

## Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

````
{
  "inputs": {
    "mode": "Teff_L",
    "points": [
      {
        "id": "Sun",
        "Teff_K": 5772,
        "L_solar": 1
      }
    ]
  },
  "expected_outputs": {
    "sampled_points": [
      {
        "id": "Sun",
        "x_Teff_K": 5772,
        "y_L_solar": 1
      }
    ],
    "rough_stage": "main-sequence-like if the overlay labels the solar neighborhood as main sequence",
    "key_curve_features": [
      "The plotted point must lie at Teff = 5772 K and L/L_sun = 1.",
      "The point is a standard solar reference anchor; no numerical zone classification can be verified without zone boundaries."
    ]
  },
  "working": "The input already uses the assumed plot units. x = Teff = 5772 K. y = L/L_sun = 1. No conversion is needed. If the implementation instead receives 3.828e26 W: y = 3.828e26 W / 3.828e26 W per L_sun = 1 L_sun."
}
````

## Related workflows

No source-defined multi-instrument workflow membership is recorded.

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json · VERIFIED_CLEAN`

- `evidence-tranche6/tranche6-results.json`

- `BOUNDARY_HAZARD_CATALOG.json`