arXiv subjects

Matteo Pracchia

Publications and source records attributed to Matteo Pracchia.

3 recordsLinked to original sources

arXiv2026

Search for gravitational waves associated with high-energy neutrinos detected by IceCube during the third observing run of LIGO-Virgo

We search for generic gravitational-wave transients associated with high-energy neutrinos detected by the IceCube Neutrino Observatory during the third Observing Run (O3) of Advanced LIGO, Advanced Virgo, and KAGRA. We perform an unmodeled, targeted search, which is sensitive to gravitational-wave signals weaker than those reported in real time or in the gravitional-wave transient catalog, and can thus uncover coincidences missed by typical neutrino follow-up searches. We find no statistically significant gravitational-wave signal and set lower bounds on the distance of possible gravitational-wave sources for different emission models.

astro-ph.HE↗

arXiv2026

Short gamma-ray burst progenitors have short delay times

Short gamma-ray bursts (SGRBs) are thought to be primarily associated with binary neutron star (BNS) mergers. The SGRB population can therefore be scrutinized for signatures of the delay time between the formation of the progenitor massive star binary and the eventual merger, which could produce an evolution of the cosmic rate density of such events whose shape departs from that of the cosmic star formation history. We therefore studied a large sample of SGRBs within a hierarchical Bayesian framework, with a particular focus on the delay time distribution (DTD) of the population. Following previous studies, we modelled the DTD either as a power-law with a minimum time delay or as a log-normal function. We considered two models for the intrinsic SGRB luminosity distribution: an empirical luminosity function with a doubly broken power-law shape and another based on a quasi-universal structured jet model. Regardless of the chosen parametrization, we found average time delays of $10\lesssim \langle \tau_\mathrm{d}\mathrm\rangle/\mathrm{Myr}\lesssim 900$ and a minimum delay time of $\tau_\mathrm{d,min}\lesssim 350\,\mathrm{Myr}$, in contrast with previous studies that found long delay times of a few gigayears. We demonstrate that the cause of the longer inferred time delays in past studies most likely resides in an incorrect treatment of selection effects

astro-ph.HE↗

arXiv2025

Short-Duration Gravitational Wave Burst Detection using Convolutional Neural Network

Detecting unmodeled gravitational wave (GW) bursts presents significant challenges due to the lack of accurate waveform templates required for matched-filtering techniques. A primary difficulty lies in distinguishing genuine signals from transient noise. Machine learning approaches, particularly convolutional neural networks (CNNs), offer promising alternatives for this classification problem. This paper presents a CNN-based pipeline for detecting short GW bursts (duration $< 10~\mathrm{s}$), adapted from an existing framework designed for longer-duration events. The CNN has been trained on core-collapse supernova (CCSN) gravitational waveform models injected into simulated Gaussian noise. The network successfully identifies these signals and generalizes to CCSN waveforms not included in the training set, showing the potential of U-Net architectures for detecting short-duration gravitational wave transients across diverse astrophysical scenarios.

gr-qc↗