LIGO Document T2100154-v1

Unidentified O3a lines found in self-gated C01 data

Document #:
Document type:
T - Technical notes
Other Versions:
Lists of unidentified lines for H1 and L1 during the O3a epoch.

Run-averaged, noise-weighted spectra were generated using 7200-s-long FFTs (Tukey-windowing) from observing quality self-gated C01 data minus CAT1 vetoes. Spectra data was inspected visually for artifacts and correlated with known non-astrophysical features. These lists may be periodically revised as additional understanding and insights are gained. Since the spectra are high-resolution and many averages are used to create the O3a run-average spectra, many more features are visible than would be when analyzing spectra made using short FFT duration and few averages. The high resolution allows to see many artifacts in different frequency bins as well as revealing weak features that need many averages to stick out of the background.

These lists contain only a subset of spectral artifacts present in the data; other vetted non-astrophysical features are also present. See See T2100153-v1. Because of the self-gating, the noise floor, especially in the 50 - 500 Hz band, is lower than non-gated C01 spectra so that more spectral artifacts are observed. These lists contain some artifacts that are seen in self-gated data only, and other artifacts that are seen only in ungated data (noted in the comment field).

Note that the files from repo with git tags appended to their filenames. For example, git tag O3a_lines_v1_2 corresponds to files with the appendix _v1_2 in their filename.

DCC Version 3.4.1, contact Document Database Administrators