Simulations of the Six-Month Intermediate Run 1 and O5 Observing Scenarios with the GWTC-4 Population Model: Detection Rates, Skymaps, and Multimessenger Parameters — February 2026 Data Release

We performed simulations of the HLV detector network configuration for the upcoming O5 observing run, estimating the expected gravitational-wave (GW) detection rates using a signal-to-noise ratio (S/N) threshold of 8. The simulated compact-binary population is drawn from the GWTC-4 FullPop-4.0 population model, ensuring consistency with the latest observational constraints on compact-object mass, spin, and merger-rate distributions. The statistics folder contains summary statistics for both the O4 and projected O5 observing scenarios, enabling direct comparisons of detection rates, source classifications, and population properties between current and anticipated detector sensitivities. Events are classified according to component masses using a standard threshold: neutron stars (NS) are defined as having masses < 3 M⊙, while black holes (BH) are defined as having masses ≥ 3 M⊙. These simulations build on previous observing-scenario studies, including the O4-HL, O4-HLV, and O5a-HL/O5a-HLV/O5b-HLV/O5c-HLV sensitivity projections.