The elusiveness of old neutron stars
arXiv:astro-ph/9802032 · doi:10.1086/305810
Abstract
Old neutron stars (ONSs) which have radiated away their internal and rotational energy may still shine if accreting the interstellar medium. Despite their large number, only two promising candidates have been detected so far and rather stringent limits on their observability follow from the analysis of ROSAT surveys. This contrasts with optimistic theoretical estimates that predicted a large number of sources in ROSAT fields. We have reconsidered the issue of ONSs observability, accounting for the spin and magnetic field evolution over the neutron star lifetime. In the framework of a spin-induced field decay model, we show that the total number of ONSs which are, at present, in the accretion stage is reduced by a factor ~5 over previous figures if the characteristic timescale for crustal current dissipation is ~ 10^8 - 10^9 yr. This brings theoretical predictions much closer to observational limits. Most ONSs should be at present in the propeller phase and, if subject to episodic flaring, they could be observable.
10 pages Latex, 5 ps figures. To be formatted with the AASTeX package. Accepted for publication in ApJ
References in corpus (2)
Cited by in corpus (24)
- Towards a Mass and Radius Determination of the Nearby Isolated Neutron Star RX J185635-3754
- Isolated Neutron Stars: Accretors and Coolers
- X-Rays from Isolated Black Holes in the Milky Way
- The proper motion and energy distribution of the isolated neutron star RX J0720.4-3125
- Bondi Accretion and the Problem of the Missing Isolated Neutron Stars
- Timing analysis of the isolated neutron star RX J0720.4-3125
- The Neutron Stars Census
- Log N -- Log S distributions of accreting and cooling isolated neutron stars
- A Limit on the Number of Isolated Neutron Stars Detected in the ROSAT Bright Source Catalog
- Propagation of Magnetized Neutron Stars Through the Interstellar Medium
- Long duration radio transients lacking optical counterparts are possibly Galactic Neutron Stars
- Timing Analysis of the Isolated Neutron Star RX J0720.4-3125 Revisited
- Vacuum Breakdown near a Black Hole Charged by Hypercritical Accretion
- Evolution of isolated neutron stars till accretion. The role of initial magnetic field
- Magnetically Accreting Isolated Old Neutron Stars
- Period distribution of old accreting isolated neutron stars
- Settling accretion on to isolated neutron stars from interstellar medium
- ROSAT Blank Field Sources I: Sample Selection and Archival Data
- On the evolutionary states of neutron stars in pre-low-mass X-ray binaries
- Evolution of isolated neutron stars in globular clusters: number of Accretors
- Electron Cyclotron Maser Emission as the Driving Mechanism in Long-Period Radio Transients
- Population synthesis of old neutron stars in the Galaxy
- ROSAT X-ray sources and exponential field decay in isolated neutron stars
- On the Possibility of the Detection of Extinct Radio Pulsars