The Galactic population and properties of young, highly energetic pulsars
Abstract
The population of young, non-recycled pulsars with spin-down energies $\dot{E} \gt 10^{35}$ erg s-1 is sampled predominantly at γ-ray and radio wavelengths. A total of 137 such pulsars are known, with partial overlap between the sources detectable in radio and γ-rays. We use a very small set of assumptions in an attempt to test whether the observed pulsar sample can be explained by a single underlying population of neutron stars. For radio emission we assume a canonical conal beam with a fixed emission height of 300 km across all spin periods and a luminosity law which depends on $\dot{E}^{0.25}$ . For γ-ray emission we assume the outer-gap model and a luminosity law which depends on $\dot{E}^{0.5}$ . We synthesize a population of fast-spinning pulsars with a birth rate of one per 100 yr. We find that this simple model can reproduce most characteristics of the observed population with two caveats. The first is a deficit of γ-ray pulsars at the highest $\dot{E}$ which we surmise to be an observational selection effect due to the difficulties of finding γ-ray pulsars in the presence of glitches without prior knowledge from radio frequencies. The second is a deficit of radio pulsars with interpulse emission, which may be related to radio emission physics. We discuss the implications of these findings.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2020
- DOI:
- 10.1093/mnras/staa2110
- arXiv:
- arXiv:2007.08681
- Bibcode:
- 2020MNRAS.497.1957J
- Keywords:
-
- pulsars: general;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted by MNRAS