# Broadband X-ray Spectroscopy of the Pulsar Wind Nebula in HESS J1640-465

## TL;DR

This study analyzes the X-ray properties of the pulsar wind nebula in HESS J1640-465 using Chandra and NuSTAR data, revealing spectral softening, high magnetic fields, and potential PeVatron status.

## Contribution

It provides updated X-ray measurements, accounts for dust scattering effects, and employs a model to suggest the nebula's potential as a PeVatron candidate.

## Key findings

- Spectral softening observed at higher energies
- High magnetic field and maximum electron energy up to PeV
- HESS J1640-465 may be a PeVatron candidate

## Abstract

We present updated measurements of the X-ray properties of the pulsar wind nebula associated with the TeV $\gamma$-ray source HESS J1640-465 derived from Chandra & NuSTAR data. We report a high $N_{H}$ value along line of sight, consistent with previous work, which led us to incorporate effects of dust scattering in our spectral analysis. Due to uncertainties in the dust scattering, we report a range of values for the PWN properties (photon index and un-absorbed flux). In addition, we fit the broadband spectrum of this source and found evidence for spectral softening and decreasing unabsorbed flux as we go to higher photon energies. We then used a one zone time dependent evolutionary model to reproduce the dynamical and multi-wavelength spectral properties of our source. Our model suggests a short spin-down time scale, a relatively higher than average magnetized pulsar wind, a strong PWN magnetic field and maximum electron energy up to PeV, suggesting HESS J1640-465 could be a PeVatron candidate.