The Parkes Multibeam Pulsar Survey – VI. Discovery and timing of 142 pulsars and a Galactic population analysis

Abstract

We present the discovery and follow‐up observations of 142 pulsars found in the Parkes 20‐cm multibeam pulsar survey of the Galactic plane. These new discoveries bring the total number of pulsars found by the survey to 742. In addition to tabulating spin and astrometric parameters, along with pulse width and flux density information, we present orbital characteristics for 13 binary pulsars which form part of the new sample. Combining these results from another recent Parkes multibeam survey at high Galactic latitudes, we have a sample of 1008 normal pulsars which we use to carry out a determination of their Galactic distribution and birth rate. We infer a total Galactic population of 30 000 ± 1100 potentially detectable pulsars (i.e. those beaming towards us) having 1.4‐GHz luminosities above 0.1 mJy kpc2. Adopting the Tauris & Manchester beaming model, this translates to a total of 155 000 ± 6000 active radio pulsars in the Galaxy above this luminosity limit. Using a pulsar current analysis, we derive the birth rate of this population to be 1.4 ± 0.2 pulsars per century. An important conclusion from our work is that the inferred radial density function of pulsars depends strongly on the assumed distribution of free electrons in the Galaxy. As a result, any analyses using the most recent electron model of Cordes & Lazio predict a dearth of pulsars in the inner Galaxy. We show that this model can also bias the inferred pulsar scaleheight with respect to the Galactic plane. Combining our results with other Parkes multibeam surveys we find that the population is best described by an exponential distribution with a scaleheight of 330 pc. Surveys underway at Parkes and Arecibo are expected to improve the knowledge of the radial distribution outside the solar circle, and to discover several hundred new pulsars in the inner Galaxy.

A New Electron-Density Model for Estimation of Pulsar and FRB Distances

“…In the next few years, the population of known pulsars increased significantly, mainly as a result of the Parkes Multibeam Pulsar Survey; several groups (e.g., Lorimer et al 2006) began to notice that NE2001 systematically underestimates the z-distance of high-latitude pulsars. To address this, Gaensler et al (2008) product is equal to the "perpendicular DM" (DM^), i.e., the DM integrated to infinity perpendicular to the Galactic disk.…”

Long-term observations of three nulling pulsars

“…The first pulsar we discuss, J1634−5107, is a 507 ms source which was discovered in the Parkes Multibeam Pulsar Survey (PMPS; Lorimer et al 2006). Nulling activity in the source was first identified in further analysis of a number of PMPS discoveries, where it was shown that the pulsar exhibits a strong radioemitting (i.e.…”

Pulsar science with the Five hundred metre Aperture Spherical Telescope

“…Each pulsar is assigned a value of P, L, R and z based on the assumed probability density functions. For the distributions in P, R and z, we use the distributions from C of Lorimer et al (2006). To compute L, we adopt the log-normal distribution found by Faucher-Giguère & Kaspi (2006).…”

“…In their study, Lorimer et al (2006) used the results from recent surveys with the Parkes Multibeam system to derive an underlying population of pulsars with an optimal set of probability density functions for pulsar period (P), 1400-MHz radio luminosity (L), Galactocentric radius (R) and height above the Galactic plane (z). We make use of these results in our simulations described below which use as a starting point model C from Lorimer et al (2006). Our simulation procedure begins by generating a population of normal pulsars which beam towards the Earth.…”

“…We performed Monte Carlo simulations following Lorimer et al (2006) using the psrpop 1 package (cf. Smits et al 2009).…”