TESS apertures contain 7–92% of the fitted 8.51-hour image signal in seven HD 172555 sectors

A neighbor can add a large cycle signal to the TESS flux of HD 172555. We fit the public 120-second images in sectors 66, 93, 94, 101, 102, 103, and 104. We hold the cycle and rapid frequencies fixed at values from an earlier SCI study. The target aperture contains 7.33–92.11% of the signed cycle signal summed over each saved image stamp. The target SAP cycle amplitude changes by a factor of 15.42. The full-stamp signed amplitude changes by a factor of 1.59. The strongest cycle pixel is near CD-64 1208 in six sectors. In sector 101, it lies at the end of a bright column. Exclusion of bright columns moves the remaining maximum near the neighbor. This is an empirical check, with no calibrated position error. Model changes and separate time-half fits give the same maximum pixel in each sector. The fractions describe the fitted cycle within each stamp. They do not measure a fraction of all stellar photons. These results add six later image tests and show a large aperture effect. We provide code, source addresses, hashes, figures, and small data files that reproduce the linear image fits. We make no new planet or comet claim.

TESS · HD 172555 · CD-64 1208 · aperture contamination · pixel analysis · stellar variability · exocomet source control · reproducible data product