Speaker
Description
Pulsar wind nebulae (PWNe) are powerful cosmic accelerators, acting as a primary source of energetic leptons in our galaxy. Their high-energy emissions, spanning from X-ray to ultra-high-energy (UHE; >100 TeV), provide a critical diagnostic for understanding acceleration and evolution of ultra-relativistic partlcles within these dynamic sources.
While one-zone models of PWN spectral energy distributions (SEDs) have been useful for estimating key parameters like magnetic field strength and maximum electron energy, they cannot explain several important observations. These include the spatially varying X-ray emission spectra and the detection of VHE/UHE emissions extending far beyond the X-ray-emitting regions. Such findings suggest a more complex internal structure and evolution than a one-zone model can account for.
To address these limitations, we have developed a multi-zone SED model. Our model incorporates particle diffusion and prescribes spatial variations in both the magnetic field and particle flow, providing a more realistic representation of PWN structure. In this presentation, we will discuss our application of this model to a sample of PWNe of various ages, present new insights gained from our analysis, and outline our methodology for ultimately incorporating both temporal and spatial evolution into our model --- a crucial next step toward a comprehensive understanding of these fascinating systems.
