The Distance of the SNR Kes 75 and PWN PSR J1846-0258 System

TL;DR

This paper refines the distance estimate to the Kes 75 supernova remnant and its pulsar PSR J1846-0258 using HI and CO spectral analysis, confirming the pulsar's youth and association with the remnant.

Contribution

It provides a new, more accurate distance measurement for Kes 75, challenging previous estimates and confirming the system's properties and age.

Findings

Kes 75 is within 13.2 kpc, likely 5.1-7.5 kpc away.

The revised distance aligns the SNR's age with the pulsar's spin-down age.

Kes 75 is confirmed as a young supernova remnant with a young pulsar.

Abstract

The supernova remnant (SNR) Kes 75/PSR J1846-0258 association can be regarded as certain due to the accurate location of young PSR J1846-0258 at the center of Kes 75 and the detected bright radio/X-ray synchrotron nebula surrounding the pulsar. We provide a new distance estimate to the SNR/pulsar system by analyzing the HI and $^{13}$CO maps, the HI emission and absorption spectra, and the $^{13}$CO emission spectrum of Kes 75. No absorption features at negative velocities strongly argue against the widely-used large distance of 19 to 21 kpc for Kes 75, and show that Kes 75 is within the Solar circle, i.e. a distance $d<$13.2 kpc. Kes 75 is likely at distance of 5.1 to 7.5 kpc because the highest HI absorption velocity is at 95 km/s and no absorption is associated with a nearby HI emission peak at 102 km/s in the direction of Kes 75. This distance to Kes 75 gives a reasonable luminosity of PSR J1846-0258 and its PWN, and also leads to a much smaller radius for Kes 75. So the age of the SNR is consistent with the spin-down age of PSR J1846-0258, confirming this pulsar as the second-youngest in the Galaxy.