- ID:
- ivo://CDS.VizieR/J/other/PASA/37.29
- Title:
- POGS-II ExGal catalog
- Short Name:
- J/other/PASA/37.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The low-frequency linearly polarised radio source population is largely unexplored. However, a renaissance in low-frequency polarimetry has been enabled by pathfinder and precursor instruments for the Square Kilometre Array. In this second paper from the POlarised GaLactic and Extragalactic All-Sky MWA Survey-the POlarised GLEAM Survey, or POGS-we present the results from our all-sky MWA Phase I Faraday Rotation Measure survey. Our survey covers nearly the entire Southern sky in the Declination range -82{deg} to +30{deg} at a resolution between around three and seven arcminutes (depending on Declination) using data in the frequency range 169-231MHz. We have performed two targeted searches: the first covering 25489 square degrees of sky, searching for extragalactic polarised sources; the second covering the entire sky South of Declination +30{deg}, searching for known pulsars. We detect a total of 517 sources with 200MHz linearly polarised flux densities between 9.9mJy and 1.7Jy, of which 33 are known radio pulsars. All sources in our catalogues have Faraday rotation measures in the range -328.07rad/m^2^ to +279.62rad/m^2^. The Faraday rotation measures are broadly consistent with results from higher-frequency surveys, but with typically more than an order of magnitude improvement in the precision, highlighting the power of low-frequency polarisation surveys to accurately study Galactic and extragalactic magnetic fields. We discuss the properties of our extragalactic and known-pulsar source population, how the sky distribution relates to Galactic features, and identify a handful of new pulsar candidates among our nominally extragalactic source population.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/474/4629
- Title:
- Polarimetry of 600 pulsars from 1.4GHz obs.
- Short Name:
- J/MNRAS/474/4629
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Over the past 13yr, the Parkes radio telescope has observed a large number of pulsars using digital filter bank backends with high time and frequency resolution and the capability for Stokes recording. Here, we use archival data to present polarimetry data at an observing frequency of 1.4GHz for 600 pulsars with spin-periods ranging from 0.036 to 8.5s. We comment briefly on some of the statistical implications from the data and highlight the differences between pulsars with high and low spin-down energy. The data set, images and table of properties for all 600 pulsars are made available in a public data archive maintained by the CSIRO.
- ID:
- ivo://CDS.VizieR/J/AJ/121/1192
- Title:
- Proper-motion measurements with the VLA
- Short Name:
- J/AJ/121/1192
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The pulsar velocity distribution provides information about the binary history of pulsar progenitors, as well as the asymmetries of the supernova events in which pulsars are born. Studies of local pulsars present a biased view of this distribution, because they preferentially select low-velocity pulsars that have remained near their birthplaces in the Galactic plane. Using the VLA, we have studied the proper motions of a large sample of distant pulsars. These pulsars are generally faint, and the expected proper motions are small. In this paper, we describe the data analysis techniques that we have developed to allow precise astrometric measurements of faint sources with the VLA. These techniques include "gating" the VLA correlator to increase the signal-to-noise ratio of the pulsar by gathering data only during the pulse. Wide-field imaging techniques, including multiband imaging to account for bandwidth smearing, were used to allow identification of multiple in-beam background sources for astrometric calibration. We present the analysis of three pulsars and demonstrate that astrometric accuracy of about 10 mas can be obtained for individual sources with our technique, allowing measurement of proper motions with errors of only a few milliarcseconds per year over our 7 year baseline.
- ID:
- ivo://CDS.VizieR/J/MNRAS/362/1189
- Title:
- Proper motions of 74 pulsars
- Short Name:
- J/MNRAS/362/1189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured the positions of 74 pulsars from regular timing observations using the Nanshan radio telescope at Urumqi Observatory between 2000 January and 2004 August (MJD 5150053240). Proper motions were determined for these pulsars by comparing their current positions with positions given in pulsar catalogues. We compare our results to earlier measurements in the literature and show that, in general, the values agree. New or improved proper motions are obtained for 16 pulsars. The effect of period fluctuations and other timing noise on the determination of pulsar positions is investigated. For our sample, the mean and rms transverse velocities are 443 and 224km/s, respectively, agreeing with previous work even though we determine distances using the new NE2001 electron density model.
- ID:
- ivo://CDS.VizieR/J/MNRAS/360/974
- Title:
- Proper motionsof pulsars
- Short Name:
- J/MNRAS/360/974
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and analyse a catalogue of 233 pulsars with proper motion measurements. The sample contains a wide variety of pulsars including recycled objects and those associated with globular clusters or supernova remnants. After taking the most precise proper motions for those pulsars for which multiple measurements are available, the majority of the proper motions (58 per cent) are derived from pulsar timing methods, 41% using interferometers and the remaining 1% using optical telescopes.
- ID:
- ivo://CDS.VizieR/J/A+A/552/A127
- Title:
- PSR J1048-5832 V and R images
- Short Name:
- J/A+A/552/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- PSR J1048-5832 is a young radio-pulsar that has recently been detected in {gamma}-rays with Fermi, and also in X-rays with Chandra and XMM-Newton. It powers a compact pulsar wind nebula visible in X-rays and is in many ways similar to the Vela pulsar. We present deep optical observations made with the ESO Very Large Telescope to search for optical counterparts of the pulsar and its nebula and to explore their multi-wavelength emission properties. The data were obtained in the V and R bands and were compared with archival data in other spectral domains.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/11
- Title:
- Pulsar rotation measures
- Short Name:
- J/ApJS/234/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the measurements of Faraday rotation for 477 pulsars observed by the Parkes 64m radio telescope and the Green Bank 100m radio telescope. Using these results, along with previous measurements for pulsars and extragalactic sources, we analyze the structure of the large-scale magnetic field in the Galactic disk. Comparisons of rotation measures of pulsars in the disk at different distances, as well as with rotation measures of background radio sources beyond the disk, reveal large-scale reversals of the field directions between the spiral arms and interarm regions. We develop a model for the disk magnetic field, which can reproduce not only these reversals but also the distribution of the observed rotation measures of background sources.
- ID:
- ivo://CDS.VizieR/J/A+AS/136/571
- Title:
- Pulsars identified from the NRAO VLA Sky Survey
- Short Name:
- J/A+AS/136/571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table1 gives the NVSS radio sources around the positions of all known pulsars. This table was generated by searching NVSS catalog, and each row gives the closest source around one pulsar. However, not all of them are pulsars, as we discussed in our paper. If there is "?" in the Notes, we had more considerations to identify the source as a pulsar. If there is nothing or just "*" in Notes, the source is believed to be the pulsar. Table 2 lists 14 strong pulsars not detected by the NVSS, or more exactly saying, not listed in the NVSS catalog. By the courtesy of Jim Condon, we found some of these pulsars are confused by nearby strong radio sources, and most of them were really scintillating during the NVSS.
- ID:
- ivo://CDS.VizieR/J/MNRAS/424/2832
- Title:
- Pulsars in {gamma}-ray sources
- Short Name:
- J/MNRAS/424/2832
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Machine learning, algorithms designed to extract empirical knowledge from data, can be used to classify data, which is one of the most common tasks in observational astronomy. In this paper, we focus on Bayesian data classification algorithms using the Gaussian mixture model and show two applications in pulsar astronomy. After reviewing the Gaussian mixture model and the related expectation-maximization algorithm, we present a data classification method using the Neyman-Pearson test. To demonstrate the method, we apply the algorithm to two classification problems. First, it is applied to the well-known period-period derivative diagram. Our second example is to calculate the likelihood of unidentified Fermi point sources being pulsars.
- ID:
- ivo://CDS.VizieR/J/A+AS/147/195
- Title:
- Pulsar spectra of radio emission
- Short Name:
- J/A+AS/147/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected pulsar flux density observations and compiled spectra of 281 objects. The database of Lorimer et al. (1995, Cat. <J/MNRAS/273/411>) has been extended to frequencies higher than 1.4GHz and lower than 300MHz. Our results show that above 100 MHz the spectra of the majority of pulsars can be described by a simple power law with average value of spectral index <{alpha}>=-1.8+/-0.2. A rigorous analysis of spectral fitting revealed only about 10% of spectra which can be modelled by the two power law. Thus, it seems that single power law is a rule and the two power law spectrum is a rather rare exception, of an unknown origin, to this rule. We have recognized a small number of pulsars with almost flat spectrum ({alpha}>=-1.0) in the wide frequency range (from 300MHz to 20GHz) as well as few pulsars with a turn-over at unusually high frequency (~1GHz).
