ExpStuckiCow

Tier B: Stucki et al. 2009, COW QBER curve to 250 km of ULL fibre

4/4 passed in 0ms

Test	What it does	Result
test_cow_dark_takeover	Dark counts are 0.0026% of QBER at 100 km and 1.08% at 250 km, so the published 5 Hz dark rate carries the whole rise.	✅ pass
test_cow_qber_curve	A baseline slot error fitted to 0.85% at 100 km predicts 1.904% at 250 km against their 1.9%; their 250 km cryostat ran unusually cold, so the agreement is not a clean prediction.	✅ pass
test_cow_rate_bounded	Their 6 kbit/s and 15 bit/s are 6.3% and 6.6% of the per-click ceiling (94.8 kbit/s, 227.5 bit/s), asserted only as inequalities.	✅ pass
test_cow_split_sensitivity	Diverting an unpublished 5% or 10% to Bob's monitoring tap moves the 250 km QBER to 1.96% or 2.02%, within 7% of their 1.9%.	✅ pass