- 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/AJ/124/601
- Title:
- Absolute positions and proper motions in NGC 188
- Short Name:
- J/AJ/124/601
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The field of direct imaging is experiencing a considerable growth in the number of available CCD mosaic imagers, especially on large telescopes. To fully exploit the astrometric potential of these imaging devices, we develop a technique, utilizing an astrometric standard, for precision transformation of pixel coordinates into a global coordinate system. We have constructed a new astrometric standard set of 1863 stars in the field of NGC 188 to derive the CCD chip constants for the NOAO CCD Mosaic Imager. The multiple-epoch data on the Mosaic's metrics indicate that this CCD mosaic device may have experienced a one-time nonelastic expansion. We also present a new determination of the pixel scale and the optical field angle distortion constants for the KPNO Mayall 4 m telescope prime focus field corrector. To establish a reliable history of the CCD mosaic imager metrics for current and potential future astrometric applications, we recommend obtaining astrometric calibrations for CCD mosaic imagers on a regular basis. Apart from mechanical positioning of the CCD mosaic camera on the telescope, noticeable changes in the thermal environment of CCD mosaic chips should also prompt new astrometric calibrations. It is shown that, following all precautions, the NOAO CCD Mosaic Imager can produce excellent astrometric results on the Mayall 4 m telescope.
- ID:
- ivo://CDS.VizieR/J/other/A+AT/25.185
- Title:
- Absolute proper motions of globular clusters
- Short Name:
- J/other/A+AT/25.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The absolute proper motions for a total of 92 globular clusters of the Milky Way (60% of all clusters included in the catalogue published by Harris, 1996, Cat. VII/195) are inferred from the UCAC2 proper motions of their likely member stars. The median formal error of the cluster proper motions is equal to 0.8marcsec/yr in both right ascension and declination, whereas the proper-motion errors of individual clusters range from 0.2 to 3marcsec/yr. Tests performed demonstrate the overall validity of the cluster motions; the resulting transverse velocities remain, on the average, virtually constant out to a heliocentric distance of 15kpc and the full space velocity of most of the clusters relative to the Galactic centre remains, on the average, unchanged near 190km/s out to a Galactocentric distance of about 20kpc, in agreement with the overall isothermal structure of the Galactic halo.
- ID:
- ivo://CDS.VizieR/J/A+A/388/168
- Title:
- Absolute proper motions of 93 open clusters
- Short Name:
- J/A+A/388/168
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We determined the mean absolute proper motion of 93 open clusters situated farther than 1 kpc from the Sun. The results are derived from the stellar proper motion data given in the Tycho2 Catalogue (<I/259>). The mean proper motion of the clusters and membership probability of individual stars were obtained from the proper motion data by applying the statistical method proposed by Sanders (1971A&A....14..226S). The measurements made use of a large number of stars, usually several tens, for each cluster. The total number of stars investigated in the fields of the clusters is 4864 of which 2021 were considered members. For 55 clusters, this is the first determination of the proper motion. The distances, ages and kinematics parameters of the clusters can be accessed at http://www.iagusp.usp.br/~wilton
- ID:
- ivo://CDS.VizieR/J/A+A/376/441
- Title:
- Absolute proper motions of 112 open clusters
- Short Name:
- J/A+A/376/441
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present mean absolute proper motions of 112 open clusters, determined using the data from the Tycho2 Catalogue (Cat. <I/259>). For 28 clusters, this is the first determination of proper motion. The measurements made use of a large number of stars (usually several tens) for each cluster. The total number of stars studied in the fields of the 164 open clusters is 5016, of which 4006 were considered members. The mean proper motions of the clusters and membership probability of individual stars were obtained from the proper motion data by applying the statistical method proposed by Sanders (1971A&A....14..226S).
- ID:
- ivo://CDS.VizieR/I/295
- Title:
- Absolute Proper motions of 59766 stars
- Short Name:
- I/295
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog PUL2 was made by photographic method in Pulkovo in accordance with Deutsch plan (KSZ, Deutch A.N., 1952IAUT....8..789D). Observations were made using Pulkovo Normal astrograph. The first epochs of photographic plates were fulfilled since 1937 till 1965, and the second ones - since 1969 till 1986. PUL2 includes 149 areas uniformly covering the North sky. The mean epoch difference is 24 years. For each area there are three pairs of plates. All plates are taken with one hour and 5 min exposure. On the plates with diffraction grating only bright reference stars were measured. For obtaining relative star proper motions the faint (15.2) reference stars we used. Relative proper motions were obtained using a six constant plate model. For obtaining fictitious proper motions of extragalactic objects (absolutization) about 700 galaxies was used. Random errors of relative star proper motions are of 5.5mas/yr in right ascension and 5.9mas/yr in declination. Errors of fictitious proper motions of galaxies are of 7.9mas/yr (mean absolutization error) for both coordinates by a representation of the Oort-Lindblad model. On the base of comparison of the common stars of PUL2 and Hipparcos catalogues the components of the residual rotation vector of the Hipparcos referently to extragalactic reference frame have been derived as follows: w(x,y,z)=(-0.98,-0.03,-1.66)+/-(0.47,0.38,0.42)mas/yr. Mean random errors of absolute bright star proper motions from comparison of PUL2 and Hipparcos catalogues were estimated as 9mas/yr in both coordinates.
- ID:
- ivo://CDS.VizieR/I/331
- Title:
- Absolute Proper motions Outside the Plane (APOP)
- Short Name:
- I/331
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of absolute proper motions and updated positions derived from the same Space Telescope Science Institute digitized Schmidt survey plates utilized for the construction of the Guide Star Catalog II. As special attention was devoted to the absolutization process and removal of position, magnitude and color dependent systematic errors through the use of both stars and galaxies, this release is solely based on plate data outside the galactic plane, i.e. |b|>=27{deg}. The resulting global zero point error is less than 0.6 mas/yr, and the precision better than 4.0mas/yr for objects brighter than R_F_=18.5, rising to 9.0mas/yr for objects with magnitude in the range 18.5<R_F_<20.0. The catalog covers 22,525 square degrees and lists 100,774,153 objects to the limiting magnitude of R_F_~20.8. Alignment with the International Celestial Reference System (ICRS) was made using 1288 objects common to the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths. As a result, the coordinate axes realized by our astrometric data are believed to be aligned with the extragalactic radio frame to within +/-0.2mas at the reference epoch J2000.0. This makes our compilation one of the deepest and densest ICRF-registered astrometric catalogs outside the galactic plane. Although the Gaia mission is poised to set the new standard in catalog astronomy and will in many ways supersede this catalog, the methods and procedures reported here will prove useful to remove astrometric magnitude- and color-dependent systematic errors from the next generation of ground-based surveys reaching significantly deeper than the Gaia catalog.
- ID:
- ivo://CDS.VizieR/J/A+A/636/A36
- Title:
- Absolute radial velocities of CARMENES M dwarfs
- Short Name:
- J/A+A/636/A36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For years, the standard procedure to measure radial velocities (RVs) of spectral observations consisted in cross-correlating the spectra with a binary mask, that is, a simple stellar template that contains information on the position and strength of stellar absorption lines. The cross-correlation function (CCF) profiles also provide several indicators of stellar activity. We present a methodology to first build weighted binary masks and, second, to compute the CCF of spectral observations with these masks from which we derive radial velocities and activity indicators. These methods are implemented in a python code that is publicly available. To build the masks, we selected a large number of sharp absorption lines based on the profile of the minima present in high signal-to-noise ratio (S/N) spectrum templates built from observations of reference stars. We computed the CCFs of observed spectra and derived RVs and the following three standard activity indicators: full-width-at-half-maximum as well as contrast and bisector inverse slope. We applied our methodology to CARMENES high-resolution spectra and obtain RV and activity indicator time series of more than 300 M dwarf stars observed for the main CARMENES survey. Compared with the standard CARMENES template matching pipeline, in general we obtain more precise RVs in the cases where the template used in the standard pipeline did not have enough S/N. We also show the behaviour of the three activity indicators for the active star YZ CMi and estimate the absolute RV of the M dwarfs analysed using the CCF RVs.
- ID:
- ivo://CDS.VizieR/J/ApJ/425/418
- Title:
- Absolute R mag of brightest cluster galaxies
- Short Name:
- J/ApJ/425/418
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured the velocity of the Local Group with respect to an inertial frame defined by the 119 Abell and Abell, Corwin, & Olowin (ACO, Cat. <VII/110A>) clusters contained within 15000km/s. The observations consist of a full-sky peculiar velocity survey with an effective depth ranging from 8000 to 11000km/s, depending on how the observations are weighted with redshift. This is the deepest peculiar velocity survey yet conducted. Clusters are selected by heliocentric redshift, and the sample is volume-limited. We use the Hoessel (1980ApJ...241..493H) relationship between the metric luminosities of the brightest clusters galaxies (BCGs) and the slope of their brightness profiles as the distance indicator. The Cousins R-band luminosity within a metric radius of 10h^-1^kpc yields a typical distance error of 16% for a single BCG.
- ID:
- ivo://CDS.VizieR/J/ApJ/721/1608
- Title:
- Absolute UV magnitudes of type Ia SNe
- Short Name:
- J/ApJ/721/1608
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z=0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1_rc_ covering ~2600-3300{AA} after removing optical light, and u~3000-4000{AA}) compared to a mid-UV filter (uvm2~2000-2400{AA}).
