PSR B1257+12: a quark star with planets?

TL;DR

This paper proposes that PSR B1257+12 might be a low-mass quark star with a very small radius and mass, explaining its unusually tiny X-ray emitting area and suggesting formation via collapse or collision.

Contribution

It introduces the hypothesis that PSR B1257+12 is a low-mass quark star, providing a possible explanation for its small X-ray emitting area and formation scenarios.

Findings

PSR B1257+12 may be a low-mass quark star.

The star's radius is estimated at about 0.6 km.

The star's mass is estimated at about 3×10^{-4} solar masses.

Abstract

A recent observation has shown that PSR B1257+12 could have quite small X-ray emitting area, only about 2000 m$^2$, which is more than three orders smaller than the canonical polar cap size. We suggest here that PSR B1257+12 could be a low-mass quark star with radius of $R \simeq 0.6$ km and mass of $M \simeq 3\times10^{-4}\msun$. Such a low-mass quark star system may form in an accretion induced collapse process or a collision process of two quark stars.