Constrain the Diffusive Transport of SEPs for Simulations with PSP Observations in the Inner Heliosphere.

Solar Energetic Particle (SEP) event is one of the most hazardous phenomena in the inner heliosphere, with particle energies ranging from tens of KeV to several GeVs. The diffusive shock acceleration (DSA) and the subsequent diffusive transport of energetic particles are heavily governed by the turbulent magnetic field. Accurate descriptions of the magnetic turbulence properties and diffusion coefficients are the critical ingredients for successful SEP simulations. Recent in-situ measurements from PSP have greatly improved our understanding of turbulent solar wind. In this work, we will examine the radial evolution of key turbulence parameters, such as turbulence energy, correlation length, spectral index, and anisotropy, based on PSP observations. We will provide a refined description of the diffusion coefficients and the corresponding mean free paths to improve the accuracy in modeling the SEP transport processes, especially the perpendicular transport.