Population Synthesis of Pulsars: Magnetic Field Effects
نویسندگان
چکیده
New results based on methods of population synthesis, concerning magnetic field effects on the evolution of pulsars are reported. The present study confirms that models with timescales for the magnetic field decay longer than the pulsar lifetime are in better agreement with data. These new simulations indicate that the diagram log(PṖ ) log(ts) alone cannot be used to test field decay models. The dispersion of the values of the initial period and magnetic field can explain the observed behaviour of the data points in such a diagram. The simulations also indicate that the statistical properties of anomalous X-ray pulsars and soft-gamma repeaters (magnetar candidates) are compatible with those derived for objects born in the high side tail of the magnetic field distribution. The predicted birth rate of neutron stars having field strengths in excess of 10 G is one object born each 750 yr.
منابع مشابه
On the absence of mildly recycled radio pulsars amongst the population of ordinary single radio pulsars
Current scenarios for the evolution of binaries predict that only 1%or less of the single radio pulsars in the galactic disk have been recycled in a binary. The fraction of such pulsars amongst the detected single radio pulsars is smaller than this. For magnetic field strengths B > 1012 G the period vs. magnetic field diagram shows no evidence for injection of pulsars at P ∼ 0.5 s. For magnetic...
متن کاملA study of the evolution of radio pulsars through improved population synthesis
We simulate the birth and evolution of radio pulsars throughout the Galaxy and their observation in a region around the Sun, using recently derived models for the velocity distribution of neutron stars and for the galactic distribution of free electrons. We confirm our previous result that the properties of the pulsar population are best described by models in which the magnetic field does not ...
متن کاملBirth and Evolution of Isolated Radio Pulsars
We investigate the birth and evolution of Galactic isolated radio pulsars. We begin by estimating their birth space velocity distribution from proper motion measurements of Brisken et al. (2002, 2003). We find no evidence for multimodality of the distribution and favor one in which the absolute one-dimensional velocity components are exponentially distributed and with a three-dimensional mean v...
متن کاملConstraints on Pulsar Evolution: The Joint Period-Spindown Distribution of Millisecond Pulsars
We calculate the joint period-spindown (P − Ṗ ) distributions of millisecond radio pulsars (MSRP) for the standard evolutionary model in order to test whether the observed MSRPs are the unequivocal descendants of millisecond X-ray pulsars (MSXP). The P − Ṗ densities implied by the standard evolutionary model compared with observations suggest that there is a statistically significant overabunda...
متن کاملRadio Quiet Pulsars with Ultra-strong Magnetic Fields
The notable absence of radio pulsars having measured magnetic dipole surface field strengths above B0 ∼ 3 × 10 13 Gauss naturally raises the question of whether this forms an upper limit to pulsar magnetization. Recently there has been increasing evidence that neutron stars possessing higher dipole spin-down fields do in fact exist, including a growing list of anomalous X-ray pulsars (AXPs) wit...
متن کامل