Value chain · CLM-0500
In plain terms
The same formula for how much microwave power a beam can carry before it destabilises the upper atmosphere gives 425 watts per square metre at one textbook set of conditions and a typical 189 across thousands of real radar measurements. That is not two methods disagreeing; it is one method fed different starting numbers.
The claim as recorded
One governing relation, the Perkins-and-Goldman-derived threshold with its Ne^-3 and Te^+4 scaling, gives a 5.8 GHz self-focusing threshold of 425 W/m2 when Usui 2008 evaluates it at a single nominal condition (Ne 1e12 m^-3, Te 1500 K), and a median of 189 W/m2 when it is evaluated over the 1,827 of 22,705 measured Millstone Hill mid-latitude radar pairs that satisfy the domain condition at 5.8 GHz. The factor of 2.25 between them is explained by the inputs alone: a factor of 1.98 comes from the in-domain median density of 1.255e12 m^-3 being above Usui's nominal 1e12, and the same implementation reproduces Usui's figure to within 0.1 per cent at Usui's own inputs.
Scope and limits
The two routes use different input plasma conditions (Usui's stated reference point vs measured mid-latitude radar distributions), so the disagreement partly reflects real condition-dependence, not only method disagreement; the self-focusing threshold spans several orders of magnitude across day/night and solar-cycle conditions (claims.md ~1716), so neither figure should be read as a single fixed limit. THESE TWO FIGURES MAY NOT BE CITED AS MUTUAL CORROBORATION OR AS AN INDEPENDENT CHECK ON ONE ANOTHER, condition added 2026-09-04. They are one relation evaluated at two input sets, and a point value cannot be compared with a distribution median as though the two were competing estimates of the same quantity. A genuine independent check would require a threshold relation not derived from Perkins and Goldman, and synthesis/calcs.md records that none was found. The 1,827-pair count is not printed in CALC-014, which gives 8.0 per cent of 22,705 rows in domain at 5.8 GHz (1,816 to 1,827 depending on rounding), so the exact count is consistent with CALC-014 but not recomputed from it (VER-1341 CONFIRMED 2026-09-19).
What it assumes
Both routes assume the same underlying Perkins-and-Goldman-derived governing relation and the same Ne^-3, Te^+4-type scaling; the Ne^-3 exponent itself is confirmed by no source (synthesis/decision.md).
Where it comes from
(Usui 2008), reproduced to better than 0.1 per cent by an implementation made here (claims.md ~2483: "32.01 and 424.73 watts per square metre"); claims.md ~2301: "Median threshold 919 W/m2 at 2.45 GHz and 189 W/m2 at 5.8 GHz."
Basis: W/m2, self-focusing threshold at 5.8 GHz; one relation at two input sets, one a point evaluation and one a distribution median
Related records
- Answers question
- QST-001 not published in this release
Cite this
energyaperture.com/c/clm-0500
CLM-0500, Energy Aperture, as of 2008; 2026-09 (comparison).
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-124
- CLM-0104A separate Japanese review worked out the same threshold from the original paper and got 32 and 425 watts per square metre. My own...CLM-0105A third party looked at the 230 watt per square metre design figure and said self-focusing may happen at 2.45 gigahertz but not at 5.8...CLM-0168In this 2008 Japanese review, the absorption figures of under 1% normally and up to about 10% at increased solar activity are not tied to...CLM-0169The 2008 Japanese review that gives the well-known 32 and 425 watts-per-square-metre self-focusing thresholds only ever says self-focusing...