- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4485
- Title:
- Absolute polarimetry observations of 33 pulsars
- Short Name:
- J/MNRAS/453/4485
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absolute polarimetry observations of 33 pulsars were carried out with the Green Bank Telescope in the 1100-1900 MHz band using the Green Bank Ultimate Pulsar Processing Instrument. This group was selected to help complete a larger sample for which accurate proper-motion measurements were available. A combination of profile analysis using the core/double cone model and polarization-angle fitting methods were applied to estimate the "fiducial" longitude of the magnetic axis for each star and refer the linear polarization angle at that point to infinite frequency. As had been found previously, a number of the pulsars are found to have fiducial polarization directions that fall either along or at right angles to their proper-motion directions, whereas upwards of a third of the stars studied show alignments that are neither parallel nor orthogonal.
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- ID:
- ivo://CDS.VizieR/J/A+A/558/A137
- Title:
- AGILE bright gamma-ray sources updated list
- Short Name:
- J/A+A/558/A137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a variability study of a sample of bright {gamma}-ray (30MeV-50GeV ) sources. This sample is an extension of the first AGILE catalogue of -ray sources (1AGL), obtained using the complete set of AGILE observations in pointing mode performed during a 2.3 year period from July 9, 2007 until October 30, 2009. The dataset of AGILE pointed observations covers a long time interval and its {gamma}-ray data archive is useful for monitoring studies of medium-to-high brightness {gamma}-ray sources. In the analysis reported here, we used data obtained with an improved event filter that covers a wider field of view, on a much larger (about 27.5 months) dataset, integrating data on observation block time scales, which mostly range from a few days to thirty days. The data processing resulted in a better characterized source list than 1AGL was, and includes 54 sources, 7 of which are new high galactic latitude (|BII|>=5) sources, 8 are new sources on the galactic plane, and 20 sources from the previous catalogue with revised positions. Eight 1AGL sources (2 high-latitude and 6 on the galactic plane) were not detected in the final processing either because of low Observing Block (OB) exposure and/or due to their position in complex galactic regions. We report the results in a catalogue of all the detections obtained in each single OB, including the variability results for each of these sources. In particular, we found that 12 sources out of 42 or 11 out of 53 are variable, depending on the variability index used, where 42 and 53 are the number of sources for which these indices could be calculated. Seven of the 11 variable sources are blazars, the others are Crab pulsar+nebula, LS I +61 303, Cyg X-3, and 1AGLR J2021+4030.
- ID:
- ivo://CDS.VizieR/J/MNRAS/424/L64
- Title:
- AGN/pulsar distinction for 2FGL sources
- Short Name:
- J/MNRAS/424/L64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dark matter annihilation signals coming from Galactic subhaloes may account for a small fraction of unassociated point sources detected in the second Fermi-LAT Catalogue (2FGL). To investigate this possibility, we present SIBYL, a Random Forest classifier that offers predictions on class memberships for unassociated Fermi-LAT sources at high Galactic latitudes using gamma-ray features extracted from the 2FGL. SIBYL generates a large ensemble of classification trees that are trained to vote on whether a particular object is an active galactic nucleus (AGN) or a pulsar. After training on a list of 908 identified/associated 2FGL sources, SIBYL reaches individual accuracy rates of up to 97.7 per cent for AGNs and 96.5 per cent for pulsars. Predictions for the 269 unassociated 2FGL sources at |b|>=10{deg} suggest that 216 are potential AGNs and 16 are potential pulsars (with majority votes greater than 70 per cent). The remaining 37 objects are inconclusive, but none is an extreme outlier. These results could guide future quests for dark matter Galactic subhaloes.
- ID:
- ivo://CDS.VizieR/J/AZh/88/22
- Title:
- Angles rotation/magnetic moment in pulsars
- Short Name:
- J/AZh/88/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data on the pulse structure and variations of the linear polarization angle at frequencies near 1GHz have been used to estimate the angles {beta} between the rotational axis and magnetic moment of the neutron stars associated with 80 pulsars.
- ID:
- ivo://CDS.VizieR/J/A+A/581/A126
- Title:
- Application of the D^3^PO algorithm
- Short Name:
- J/A+A/581/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the 6.5yr all-sky data from the Fermi LAT restricted to gamma-ray photons with energies between 0.6-307.2GeV. We present a non-parametric reconstruction of the diffuse photon flux up to several hundred GeV, its all-sky spectral index map, and its angular power spectrum. We decompose the diffuse emission into a cloud-like abd a bubble-like component and analyze their spectra. Additionally, we wrote up a catalog of source candidates that includes 3106 sources. For each source we report the location in the sky, flux, spectral index, and possible associations with sources from the second and third Fermi source catalog.
- ID:
- ivo://CDS.VizieR/J/ApJ/812/81
- Title:
- Arecibo Pulsar-ALFA (PALFA) survey. IV.
- Short Name:
- J/ApJ/812/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The on-going Arecibo Pulsar-ALFA (PALFA) survey began in 2004 and is searching for radio pulsars in the Galactic plane at 1.4GHz. Here we present a comprehensive description of one of its main data reduction pipelines that is based on the PRESTO software and includes new interference-excision algorithms and candidate selection heuristics. This pipeline has been used to discover 40 pulsars, bringing the survey's discovery total to 144 pulsars. Of the new discoveries, eight are millisecond pulsars (MSPs; P<10ms) and one is a Fast Radio Burst (FRB). This pipeline has also re-detected 188 previously known pulsars, 60 of them previously discovered by the other PALFA pipelines. We present a novel method for determining the survey sensitivity that accurately takes into account the effects of interference and red noise: we inject synthetic pulsar signals with various parameters into real survey observations and then attempt to recover them with our pipeline. We find that the PALFA survey achieves the sensitivity to MSPs predicted by theoretical models but suffers a degradation for P>~100ms that gradually becomes up to ~10 times worse for P>4s at DM<150pc/cm^3^. We estimate 33+/-3% of the slower pulsars are missed, largely due to red noise. A population synthesis analysis using the sensitivity limits we measured suggests the PALFA survey should have found 224+/-16 un-recycled pulsars in the data set analyzed, in agreement with the 241 actually detected. The reduced sensitivity could have implications on estimates of the number of long-period pulsars in the Galaxy.
- ID:
- ivo://CDS.VizieR/B/psr
- Title:
- ATNF Pulsar Catalogue
- Short Name:
- B/psr
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue is a compilation of the principal observed parameters of pulsars, including positions, timing parameters, pulse widths, flux densities, proper motions, distances, and dispersion, rotation, and scattering measures. It also lists the orbital elements of binary pulsars, and some commonly used parameters derived from the basic measurements. The catalogue includes all published rotation-powered pulsars, including those detected only at high energies. It also includes Anomalous X-ray Pulsars (AXPs) and Soft Gamma-ray Repeaters (SGRs) for which coherent pulsations have been detected. However, it excludes accretion-powered pulsars such as Her X-1 and the recently discovered X-ray millisecond pulsars.
- ID:
- ivo://CDS.VizieR/J/A+A/416/1037
- Title:
- BVRIK Photometry for the field of 4U 0142+61
- Short Name:
- J/A+A/416/1037
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new optical and infrared observations of the counterpart to the Anomalous X-ray Pulsar (AXP) 4U 0142+61 taken with the Keck I telescope. The counterpart is found to be variable in the infrared. This contrasts with our optical observations, which do not show any evidence for variability. Apart from the variability the AXP shows a remarkable spectral energy distribution. In particular, we find a sudden drop in flux going from V to B, presumably due to a spectral feature. We compare our results to those obtained for the two other securely identified AXP counterparts, to 1E 2259+586 and 1E 1048.1-5937. 4U 0142+61 is very similar to the former source in its X-ray timing and spectral properties, and we find that this similarity extends to the quiescent infrared to X-ray flux ratio. For 1E 1048.1-5937, which has different X-ray properties, the situation is less clear: in one observation, the infrared to X-ray flux ratio was much larger, but another observation gave an upper limit which is consistent with that observed for 4U 0142+61. Assuming the quiescent ratios are all similar, we estimate the optical and infrared brightnesses for the three AXPs that remain to be identified as well as for the four Soft Gamma-ray Repeaters. We also discuss briefly how the observed optical and infrared emission might arise, in particular in the context of the magnetar model.
- ID:
- ivo://CDS.VizieR/VII/189
- Title:
- Catalog of Pulsars
- Short Name:
- VII/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue is a compilation of the principal observed parameters of 706 pulsars (updated from 558 pulsars in the previous version), including positions, timing parameters, pulse widths, flux densities, proper motions, distances, and dispersion, rotation, and scattering measures. It also lists the orbital elements of binary pulsars, and some commonly used parameters derived from the basic measurements. Uncertainties are quoted for most quantities.
- ID:
- ivo://CDS.VizieR/VII/156
- Title:
- Catalog of 558 Pulsars
- Short Name:
- VII/156
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue is an up-to-date compilation of the principal observed parameters of 558 pulsars, including positions, timing parameters, pulse widths, flux densities, proper motions, distances, and dispersion, rotation, and scattering measures. It also lists the orbital elements of binary pulsars, and some commonly used parameters derived from the basic measurements. Uncertainties are quoted for most quantities.
