# Discovery of X-ray emission from the young radio pulsar PSR J1357-6429

## TL;DR

This paper reports the first X-ray detection of the young pulsar PSR J1357-6429, analyzing its spectrum, luminosity, and emission properties, and setting limits on pulsar wind nebula and pulsed emission.

## Contribution

First X-ray detection of PSR J1357-6429 with spectral analysis and constraints on nebula and pulsed emission properties.

## Key findings

- X-ray spectrum fits a power-law plus blackbody model.
- X-ray luminosity is about 1.2E+32 erg/s at 2.5 kpc.
- No pulsed X-ray emission detected, with an upper limit of 30%.

## Abstract

We present the first X-ray detection of the very young pulsar PSR J1357-6429 (characteristic age of 7.3 kyr) using data from the XMM-Newton and Chandra satellites. We find that the spectrum is well described by a power-law plus blackbody model, with photon index Gamma=1.4 and blackbody temperature kT=160 eV. For the estimated distance of 2.5 kpc, this corresponds to a 2-10 keV luminosity of about 1.2E+32 erg/s, thus the fraction of the spin-down energy channeled by PSR J1357-6429 into X-ray emission is one of the lowest observed. The Chandra data confirm the positional coincidence with the radio pulsar and allow to set an upper limit of 3E+31 erg/s on the 2-10 keV luminosity of a compact pulsar wind nebula. We do not detect any pulsed emission from the source and determine an upper limit of 30% for the modulation amplitude of the X-ray emission at the radio frequency of the pulsar.