2026/07/20 by Raul Rodriguez, George Alestas, Sachiko Kuroyanagi +1
Physics and Astronomy · #astro-ph.IM #gr-qc
Primordial black holes in the planetary-mass range have attracted renewed interest; however, the search for gravitational waves from such binaries remains challenging due to their long-lived nature. In this work, we present, define, and validate a fully operational search pipeline developed to detect planetary-mass binaries during their inspiral phase. We use the Viterbi algorithm, a dynamic programming technique that recovers the most likely track based on a Hidden Markov Model. To enhance its performance, we introduce a novel time-frequency representation of the data and a candidate isolation procedure that separates signals from background noise. The evaluation of candidates is carried out using the two detection statistics, nσ and NMSE, which quantify the power significance and the consistency with the expected binary evolution. We then validate the search method using O3 LIGO Hanford data with a population of injected signals. The pipeline is able to recover most of the signals with a fixed false-alarm ratio of 3%, covering Galactic scales across most of the parameter space and reaching luminosity distances \gtrsim 100 kpc in the most sensitive region. For each candidate, we also obtain an estimate of the system's chirp mass, whose accuracy remains high throughout the detectable range, enabling a rapid characterization of the system upon detection.