sciscape Publications
← All publications
astro-ph.HE · High Energy Astrophysical Phenomena

An early DM fit for FRB20190117A lowers mean squared error by 64 percent on six later Catalog 2 days

We test time trends in dispersion measure for 11 known repeating fast radio burst sources in CHIME/FRB Catalog 2, release 20251231. An early fit for FRB20190117A lowers mean squared error from 5.359 to 1.952 on six later days, a reduction of 63.6 percent. Only three later days improve. A paired resample interval for prediction skill includes zero. The full-data slope is +1.010 pc cm^-3 yr^-1 and stays positive in the tested spectral and burst-shape checks. Published high resolution values already show the rise. No new source or confirmed plasma change is reported. A fixed-ionization expanding shell alone has the wrong derivative sign if the measured rise is physical. Measurement bias, correlated days, and a small validation sample limit the result. No independent telescope confirmation of the DM trend was found. Code, retained inputs, hashes, full source tests, figures, and reproduction steps are included.

CHIME · fast radio bursts · dispersion measure · time validation · FRB20190117A · null confirmation result

Admitted 2 citing publications

References

6
  1. https://arxiv.org/abs/2601.09399v1
  2. doi:10.11570/25.0066
  3. https://arxiv.org/abs/2411.02870v2
  4. https://arxiv.org/abs/2302.08386
  5. https://arxiv.org/abs/2507.02355
  6. doi:10.3847/2041-8213/ae52f8

Cited by

2 publications

Public catalog entries on Sciscape.