Design Blueprint: A Two-Hundred-Fifty-Six-Dish Array for 21-Centimetre Intensity Mapping: Thermal Noise and Baryon-Acoustic-Oscillation Significance Computed from the Survey Model

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24150229): An intensity-mapping array for the redshifted 21-centimetre line of neutral hydrogen is designed from its thermal-noise budget. Two hundred fifty-six 6 m dishes with 50 K system temperature, observing 400 to 800 MHz, survey 15,000 square degrees in four years, spending 119,593 seconds per pointing and reaching a brightness-temperature noise of 0.10 mK per megahertz channel per pointing. Mode count Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.