HESS J1632-478: an energetic relic

TL;DR

This study identifies HESS J1632-478 as an energetic pulsar wind nebula with a complex spectral energy distribution, using multi-wavelength data to analyze its emission mechanisms and physical properties.

Contribution

First detailed multi-wavelength analysis of HESS J1632-478 confirming its nature as a pulsar wind nebula and characterizing its spectral features and physical parameters.

Findings

HESS J1632-478 is a pulsar wind nebula about 10^4 years old.

The nebula's luminosity is about 10% of the pulsar's spin-down power.

The spectral energy distribution shows two prominent bumps in UV and TeV energies.

Abstract

HESS J1632-478 is an extended and still unidentified TeV source in the galactic plane. In order to identify the source of the very high energy emission and to constrain its spectral energy distribution, we used a deep observation of the field obtained with XMM-Newton together with data from Molonglo, Spitzer and Fermi to detect counterparts at other wavelengths. The flux density emitted by HESS J1632-478 peaks at very high energies and is more than 20 times weaker at all other wavelengths probed. The source spectrum features two large prominent bumps with the synchrotron emission peaking in the ultraviolet and the external inverse Compton emission peaking in the TeV. HESS J1632-478 is an energetic pulsar wind nebula with an age of the order of 10^4 years. Its bolometric (mostly GeV-TeV) luminosity reaches 10% of the current pulsar spin down power. The synchrotron nebula has a size of 1 pc and contains an unresolved point-like X-ray source, probably the pulsar with its wind termination shock.