PulSKASim: A Pulsar Simulator for SKA-Scale Interferometric Observations

Abstract

Accurate simulation of pulsar flux variability is critical for testing Square Kilometre Array (SKA) interferometric pipelines. However, most existing simulators neglect the effects of integration time and related observational parameters, limiting their realism and utility for interferometric end-to-end testing. To address these shortcomings, we develop a Pulsar Simulator for SKA-scale interferometric observations (PulSKASim), which models pulsar flux evolution across pulsar period, maximum flux, duty cycle, and noise, accounting for integration time, sampling, and observation duration, and naturally models flux smoothing that arises from finite integration within each dump time. PulSKASim generates synthetic measurement sets using functions in simulators for radio interferometers, such as OSKAR and Pyuvsim, where each snapshot contains pulsars with controlled flux levels, enabling realistic per-time-slot experiments. This simulator allows for detailed assessment of calibration, imaging, and detection pipelines under realistic SKA-like conditions, bridging pulsar variability modelling with interferometric simulation in a way not achievable by existing tools.

Figures (3)

• Figure 1: Structure of PulSKASim.
• Figure 2: Fidelity assessment. Left: Frequency spectra of PSR J0901-4046 and the noise-free PulSKASim simulation ($T=75.886\mathrm{s}$, $T_s=1.999\mathrm{s}$, $D=1.4/360$, $T_\mathrm{sim}=3000\mathrm{s}$, $\sigma_n=0.0$). Middle: Comparison of the original and high-pass filtered signals, showing the effect of low-frequency removal. Right: Frequency spectrum of the simulated signal with real-noise pattern compared to that of the real signal.
• Figure 3: Computation times in (Left) linear and (Right) logarithmic representations.