- ID:
- ivo://CDS.VizieR/J/AJ/162/21
- Title:
- PS1 photometry of 2863 ICRF3 quasars
- Short Name:
- J/AJ/162/21
- Date:
- 14 Mar 2022 06:53:33
- Publisher:
- CDS
- Description:
- We make use of individual (epoch) detection data from the Pan-STARRS "3{pi}" survey for 2863 optical ICRF3 counterparts in the five wavelength bands g, r, i, z, and y, published as part of the Data Release 2. A dedicated method based on the Functional Principal Component Analysis is developed for these sparse and irregularly sampled data. With certain regularization and normalization constraints, it allows us to obtain uniform and compatible estimates of the variability amplitudes and average magnitudes between the passbands and objects. We find that the starting assumption of affinity of the light curves for a given object at different wavelengths is violated for several percent of the sample. The distributions of rms variability amplitudes are strongly skewed toward small values, peaking at ~0.1mag with tails stretching to 2mag. Statistically, the lowest variability is found for the r band and the largest for the reddest y band. A small "brighter-redder" effect is present, with amplitudes in y greater than amplitudes in g in 57% of the sample. The variability versus redshift dependence shows a strong decline with z toward redshift 3, which we interpret as the time dilation of the dominant time frequencies. The colors of radio-loud ICRF3 quasars are correlated with redshift in a complicated, wavy pattern governed by the emergence of brightest emission lines within the five passbands.
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- ID:
- ivo://CDS.VizieR/J/A+A/631/A148
- Title:
- PSZ2 cluster candidates. II.
- Short Name:
- J/A+A/631/A148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second legacy catalog of Planck Sunyaev-Zeldovich (SZ) sources, hereafter PSZ2, provides the largest galaxy cluster sample selected by means of the SZ signature of the clusters in a full sky survey. In order to fully characterize this PSZ2 sample for cosmological studies, all the members should be validated and the physical properties of the clusters, including mass and redshift, should be derived. However, at the time of its publication, roughly 21% of the 1653 PSZ2 members had no known counterpart at other wavelengths. Here, we present the second and last year of observations of our optical follow-up program 128-MULTIPLE-16/15B (hereafter LP15), which has been developed with the aim of validating all the unidentified PSZ2 sources in the northern sky with declinations higher than -15{deg} that have no correspondence in the first Planck catalog PSZ1. The description of the program and the first year of observations have been presented previously. The LP15 program was awarded 44 observing nights that were spread over two years with the Isaac Newton Telescope (INT), the Telescopio Nazionale Galileo (TNG), and the Gran Telescopio Canarias (GTC), all at Roque de los Muchachos Observatory (La Palma). Following the same method as described previously, we performed deep optical imaging for more than 200 sources with the INT and spectroscopy for almost 100 sources with the TNG and GTC at the end of the LP15 program. We adopted robust confirmation criteria based on velocity dispersion and richness estimates for the final classification of the new galaxy clusters as the optical counterparts of the PSZ2 detections. Here, we present the observations of the second year of LP15, as well as the final results of the program. The full LP15 sample comprises 190 previously unidentified PSZ2 sources. Of these, 106 objects were studied before, while the remaining sample (except for 6 candidates) has been completed in the second year and is discussed here. In addition to the LP15 sample, we here study 42 additional PSZ2 objects that were originally validated as real clusters because they matched a WISE or PSZ1 counterpart, but they had no measured spectroscopic redshift. In total, we confirm the optical counterparts for 81 PSZ2 sources after the full LP15 program, 55 of them with new spectroscopic information. Forty of these 81 clusters are presented in this paper. After the LP15 observational program the purity of the PSZ2 catalog has increased from 76.7% originally to 86.2%. In addition, we study the possible reasons for false detection, and we report a clear correlation between the number of unconfirmed sources and galactic thermal dust emission.
- ID:
- ivo://CDS.VizieR/I/326
- Title:
- Pulkovo Catalogue of Reference Stars around GRS
- Short Name:
- I/326
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Pulkovo catalogue of reference stars inside 78 fields around galactic radio stars (Pul GRS) of northern sky from H.G. Walter's list (1990A&AS...86..357W) was created. The coordinates of 12495 stars was obtained from the photographic plates of Pulkovo Normal Astrograph (NA, 33/346), which was photographed in 1994-1999 years. Size of worked fields (radius about 20-40 angular seconds) was determined from the resolved problem and having technical resources: modern dimensions of CCD-detector. Precise astronometric coordinates of stars were intending for optical control beyond the positions of radio sources (GRS) by means of CCD-observation. The galactic radio stars can be the frames at the definition of connection between the existed ground and cosmic astronometric reference coordinate sets. Coordinate calculation was realization with used reference stars from catalogue Tycho-2 (ICRF, J2000.0). Error of a unit of weight from reduction coordinates was resulted nearly 0.12"-0.27" (at a number of reference stars were from 12 to 50). Internal precision of catalogue was obtained from 0.02 to 0.20 arcseconds at the both coordinates.
- 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/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).
- ID:
- ivo://CDS.VizieR/J/A+A/469/607
- Title:
- Pulsar subpulse modulation properties at 92cm
- Short Name:
- J/A+A/469/607
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A large sample of pulsars has been observed to study their subpulse modulation at an observing wavelength (when achievable) of both 21 and 92 cm using the Westerbork Synthesis Radio Telescope. In this paper we present the 92-cm data and a comparison is made with the already published 21-cm results. The main goals are to determine what fraction of the pulsars have drifting subpulses, whether those pulsars share some physical properties and to find out if subpulse modulation properties are frequency dependent. We analysed 191 pulsars at 92-cm searching for subpulse modulation using fluctuation spectra. The sample of pulsars is as unbiased as possible towards any particular pulsar characteristics.
- ID:
- ivo://CDS.VizieR/J/A+A/492/923
- Title:
- Pulsar Timing for Fermi Gamma-ray Space Telescope
- Short Name:
- J/A+A/492/923
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a comprehensive pulsar monitoring campaign for the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The detection and study of pulsars in gamma rays give insights into the populations of neutron stars and supernova rates in the Galaxy, into particle acceleration mechanisms in neutron star magnetospheres, and into the "engines" driving pulsar wind nebulae. LAT's unprecedented sensitivity between 20MeV and 300GeV together with its 2.4sr field-of-view makes detection of many gamma-ray pulsars likely, justifying the monitoring of over two hundred pulsars with large spin-down powers. To search for gamma-ray pulsations from most of these pulsars requires a set of phase-connected timing solutions spanning a year or more to properly align the sparse photon arrival times. We describe the choice of pulsars and the instruments involved in the campaign.
- ID:
- ivo://CDS.VizieR/J/A+A/586/A92
- Title:
- Pulse profiles of 100 radio pulsars
- Short Name:
- J/A+A/586/A92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- LOFAR offers the unique capability of observing pulsars across the 10-240MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well suited for studying the frequency evolution of pulse profile morphology caused by both intrinsic and extrinsic effects such as changing emission altitude in the pulsar magnetosphere or scatter broadening by the interstellar medium, respectively. The magnitude of most of these effects increases rapidly towards low frequencies. LOFAR can thus address a number of open questions about the nature of radio pulsar emission and its propagation through the interstellar medium. We present the average pulse profiles of 100 pulsars observed in the two LOFAR frequency bands: high band (120-167MHz, 100 profiles) and low band (15-62MHz, 26 profiles). We compare them with Westerbork Synthesis Radio Telescope (WSRT) and Lovell Telescope observations at higher frequencies (350 and 1400MHz) to study the profile evolution. The profiles were aligned in absolute phase by folding with a new set of timing solutions from the Lovell Telescope, which we present along with precise dispersion measures obtained with LOFAR. We find that the profile evolution with decreasing radio frequency does not follow a specific trend; depending on the geometry of the pulsar, new components can enter into or be hidden from view. Nonetheless, in general our observations confirm the widening of pulsar profiles at low frequencies, as expected from radius-to-frequency mapping or birefringence theories.
- ID:
- ivo://CDS.VizieR/J/AJ/144/150
- Title:
- QCAL-1 43 GHz Calibrator Survey
- Short Name:
- J/AJ/144/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the catalog of correlated flux densities in three ranges of baseline projection lengths of 637 sources from a 43GHz (Q band) survey observed with the Korean VLBI Network. Of them, 14 objects used as calibrators were previously observed, but 623 sources have not been observed before in the Q band with very long baseline interferometry (VLBI). The goal of this work in the early science phase of the new VLBI array is twofold: to evaluate the performance of the new instrument that operates in a frequency range of 22-129GHz and to build a list of objects that can be used as targets and as calibrators. We have observed the list of 799 target sources with declinations down to -40{deg}. Among them, 724 were observed before with VLBI at 22GHz and had correlated flux densities greater than 200mJy. The overall detection rate is 78%. The detection limit, defined as the minimum flux density for a source to be detected with 90% probability in a single observation, was in the range of 115-180mJy depending on declination. However, some sources as weak as 70mJy have been detected. Of 623 detected sources, 33 objects are detected for the first time in VLBI mode. We determined their coordinates with a median formal uncertainty of 20mas. The results of this work set the basis for future efforts to build the complete flux-limited sample of extragalactic sources at frequencies of 22GHz and higher at 3/4 of the celestial sphere.
- ID:
- ivo://CDS.VizieR/J/A+A/427/387
- Title:
- QORG catalog of radio/X-ray sources
- Short Name:
- J/A+A/427/387
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The QUASARS.ORG Catalogues align and overlay the year 2001/2 releases of the ROSAT HRI, RASS, PSPC and WGA X-ray catalogues, the NVSS (2002), FIRST (2003) and SUMSS (2003) radio catalogues, the Veron QSO catalogue (2003) and various galaxy/star reference catalogues onto the optical APM and USNO-A catalogues. These catalogues display calculated percentage probabilities for each optical radio/X-ray associated object of its likelihood of being a quasar, galaxy, star, or erroneous radio/X-ray association. The main Master catalogue (master.dat) displays all 501,761 radio/X-ray associated optical objects and known quasars which are optically detected in APM/USNO-A. Up to six radio/X-ray catalog identifications are presented for each optical object, plus any double radio lobes (21,498 of these). These are superimposed (and laterally fitted) onto a 670,925,779-object optical background which combines APM and USNO-A data. The Free-Lunch catalogue is a concise easy-to-read variant of the Master catalogue showcasing just one X-ray and/or radio identification for each object. This catalogue is the original version which was publicized to show astronomers that there *is* a free lunch after all! There is also a subset catalogue of QSO candidates, and a subset catalogue of known QSOs/galaxies/stars. Objects presented in this catalogue are those optical APM/USNO-A objects which are associated with X-ray/radio detections, or any optically-found catalogued QSO/AGN/Bl Lac objects, with confidence >40% of being a radio/X-ray emitting optical object. There are 501,761 objects included in all (including 48,285 catalogued quasars), representing the 99.4% coverage of the sky available from the APM and USNO-A. Each object is shown as one line bearing the position in equatorial coordinates, red and blue optical magnitudes (recalibrated) and PSF class, calculated probabilities of the object being, separately, a quasar, galaxy, star, or erroneous radio/X-ray association, any radio identification from each of the NVSS, FIRST and SUMSS surveys, including candidate double-lobe detections, any X-ray identification from each of the ROSAT HRI, RASS, PSPC and WGA surveys, including fluxes and field shifts of those identifications, plus, if already catalogued, the object name and redshift where applicable. The QORG catalogue and supporting data can be accessed from the catalogue home page at http://quasars.org/qorg-data.htm Questions or comments may be directed to eric@flesch.org
