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311. low-ionization structures around NGC 1360
ID:
ivo://CDS.VizieR/J/MNRAS/473/2275
Title:
low-ionization structures around NGC 1360
Short Name:
J/MNRAS/473/2275
Date:
21 Oct 2021
Publisher:
CDS
Description:
Whether planetary nebulae (PNe) are predominantly the product of binary stellar evolution as some population synthesis models (PSM) suggest remains an open question. Around 50 short-period binary central stars (P~1d) are known, but with only four with measured orbital periods over 10 d, our knowledge is severely incomplete. Here we report on the first discovery from a systematic Southern African Large Telescope (SALT) High Resolution Spectrograph (HRS) survey for long-period binary central stars. We find a 142d orbital period from radial velocities of the central star of NGC 1360, HIP 16566. NGC 1360 appears to be the product of common-envelope (CE) evolution, with nebula features similar to post-CE PNe, albeit with an orbital period considerably longer than expected to be typical of post-CE PSM. The most striking feature is a newly identified ring of candidate low-ionization structures. Previous spatiokinematic modelling of the nebula gives a nebula inclination of 30{deg}+/-10{deg}, and assuming the binary nucleus is coplanar with the nebula, multiwavelength observations best fit a more massive, evolved white dwarf (WD) companion. A WD companion in a 142d orbit is not the focus of many PSM, making NGC 1360 a valuable system with which to improve future PSM work. HIP 16566 is amongst many central stars in which large radial velocity variability was found by low-resolution surveys. The discovery of its binary nature may indicate long-period binaries may be more common than PSM models predict.
312. Low-z BQS Quasars
ID:
ivo://CDS.VizieR/J/MNRAS/263/425
Title:
Low-z BQS Quasars
Short Name:
J/MNRAS/263/425
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
313. LQRF: Large Quasar Reference Frame
ID:
ivo://CDS.VizieR/I/313
Title:
LQRF: Large Quasar Reference Frame
Short Name:
I/313
Date:
21 Oct 2021
Publisher:
CDS
Description:
The LQRF (Large Quasar Reference Frame) was built with the care of avoiding wrong matches of its constituents quasars, of homogenizing the astrometry from the different catalogs and lists from which the constituent quasars are gathered, and of attaining the milli-arcsec global alignment to the ICRF (International Celestial Reference Frame), as well as typical individual source position accuracies even to better than 100 milli-arcsec. Starting from the updated and presumably complete LQAC (Large Quasar Astrometric Catalog) list of QSOs, initial optical positions for those quasars are found in the USNO B1.0 and GSC2.3 catalogs, and from the SDSS Data Release 5. The initial positions are next placed onto UCAC2 based reference frames, following by an alignment to the ICRF, as well as of the most precise sources from the VLBA calibrator list and from the VLA calibrator list - when reliable optical counterparts exist. Finally the LQRF axes are inspected through spherical harmonics, contemplating right ascension, declination and magnitude terms.
314. LUT Survey Catalogue Data Release 1
ID:
ivo://CDS.VizieR/I/335
Title:
LUT Survey Catalogue Data Release 1
Short Name:
I/335
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an near-ultraviolet star catalogue extracted from the Lunar-based Ultraviolet Telescope (LUT) survey program. LUT's observable sky area is a circular belt around the Moon's north pole, and the survey program covers a preferred area for about 2400 square degrees which includes a region of the Galactic plane. All the sources have signal-to-noise ratio larger than 5, and the corresponding magnitude limit is typically 14.4mag, which can be deeper as ~16 mag if the stray light contamination is in the lowest level. A total number of 86,467 stars are recorded in the catalogue.
315. MAP observations of the position of Procyon
ID:
ivo://CDS.VizieR/J/AJ/131/1015
Title:
MAP observations of the position of Procyon
Short Name:
J/AJ/131/1015
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the analysis of observations of Procyon obtained with the Multichannel Astrometric Photometer during the years 1986-2004. While the results significantly increase the precision of the estimated characteristics of the components of the system, they are generally in good agreement with the most recent studies.
316. Map of foreground masks for Planck
ID:
ivo://CDS.VizieR/J/A+A/578/A44
Title:
Map of foreground masks for Planck
Short Name:
J/A+A/578/A44
Date:
21 Oct 2021
Publisher:
CDS
Description:
We test for foreground residuals in the foreground cleaned Planck Cosmic Microwave Background (CMB) maps outside and inside U73 mask commonly used for cosmological analysis. The aim of this paper is to introduce a new method to validate masks by looking at the differences in cleaned maps obtained by different component separation methods. By analyzing the power spectrum as well as the mean, variance and skewness of needlet coefficients on bands outside and inside the U73 mask we first confirm that the pixels already masked by U73 are highly contaminated and cannot be used for cosmological analysis. We further find that the U73 mask needs extension in order to reduce large scale foreground residuals to a level of less than 20% of the standard deviation of CMB fluctuations within the bands closest to the galactic equator. We also find 276 point sources in the cleaned foreground maps which are currently not masked by the U73 mask. Our final publicly available extended mask leaves 65.9% of the sky for cosmological analysis. Note that this extended mask may be important for analyses on local sky patches; in full sky analyses the additional residuals near the galactic equator may average out.
317. Mars Express astrometric observations of Phobos
ID:
ivo://CDS.VizieR/J/A+A/488/361
Title:
Mars Express astrometric observations of Phobos
Short Name:
J/A+A/488/361
Date:
21 Oct 2021
Publisher:
CDS
Description:
New astrometric measurements for Phobos are reported on the basis of 69 SRC (Super Resolution Channel) images obtained during 28 Mars Express Phobos flybys executed between 2004 and 2007. The measurements have been made using a newly developed technique which involves positional measurements of surface control points and verification of camera pointing by background stars. The astrometric positions are in excellent agreement with currently available Phobos orbit models. However, we find remaining systematic offsets of 1.5-2.6km, with Phobos ahead of the predicted position along its track. Our observations will be a basis for further improvements in the Phobos ephemeris. The methods we have developed will be useful for astrometric tracking of planetary or asteroidal targets and spacecraft optical navigation in future planetary missions.
318. Mars Express astrometric obs. of Martian moons
ID:
ivo://CDS.VizieR/J/A+A/614/A15
Title:
Mars Express astrometric obs. of Martian moons
Short Name:
J/A+A/614/A15
Date:
21 Oct 2021
Publisher:
CDS
Description:
Both Martian moons, Phobos and Deimos, have been observed during several imaging campaigns by the SRC on Mars Express. Several tens of images are obtained during mutual event observations - when the Martian moons are both observed or together with another solar system body. These observations provide new opportunities to determine the bodies' positions in their orbits. A method was sought to automate the observation of the positions of the imaged bodies. Within one image sequence a similarly accurate localization of the objects in all images should be possible. Shape models of Phobos and Deimos are applied to simulate the appearance of the bodies in the images. Matching the illuminated simulation against the observation provides a reliable determination of the bodies' location within the image. To enhance the matching confidence several corrections need to be applied to the simulation to closely reconstruct the observation. In total 884 relative positions between the different objects are provided.
319. Mass determination using microlensing by Gaia
ID:
ivo://CDS.VizieR/J/A+A/640/A83
Title:
Mass determination using microlensing by Gaia
Short Name:
J/A+A/640/A83
Date:
15 Dec 2021 08:30:09
Publisher:
CDS
Description:
Astrometric gravitational microlensing can be used to determine the mass of a single star (the lens) with an accuracy of a few percent. To do so, precise measurements of the angular separations between lens and background star with an accuracy below 1 milli-arcsecond at different epochs are needed. Therefore only the most accurate instruments can be used. However, since the timescale is on the order of months to years, the astrometric deflection might be detected by Gaia, even though each star is only observed on a low cadence. We want to show how accurately Gaia can determine the mass of the lensing star. Using conservative assumptions based on the results of the second Gaia data release (GaiaDR2), we simulated the individual Gaia measurements for 501 predicted astrometric microlensing events during the Gaia era (2014.5 - 2026.5). For this purpose we used the astrometric parameters of Gaia DR2, as well as an approximative mass based on the absolute G magnitude. By fitting the motion of the lens and source simultaneously, we then reconstructed the 11 parameters of the lensing event. For lenses passing by multiple background sources, we also fitted the motion of all background sources and the lens simultaneously. Using a Monte-Carlo simulation we determined the achievable precision of the mass determination. We find that Gaia can detect the astrometric deflection for 114 events. Furthermore, for 13 events Gaia can determine the mass of the lens with a precision better than 15% and for 13 + 21 = 34 events with a precision of 30% or better.
320. 2MASS J18212815+1414010 field stars
ID:
ivo://CDS.VizieR/J/MNRAS/455/357
Title:
2MASS J18212815+1414010 field stars
Short Name:
J/MNRAS/455/357
Date:
21 Oct 2021
Publisher:
CDS
Description:
We used the OSIRIS camera at the 10.4m Gran Telescopio Canarias (GTC) to monitor the astrometric motion of the L4.5 dwarf 2M1821+14 over 17 months. The astrometric residuals of 11 epochs have an rms dispersion of 0.4mas, which is larger than the average precision of 0.23mas per epoch and hints towards an additional signal or excess noise. Comparison of the point-spread functions in OSIRIS and FORS2/VLT images reveals no differences critical for high-precision astrometry, despite the GTC's segmented primary mirror. We attribute the excess noise to an unknown effect that may be uncovered with additional data. For 2M1821+14, we measured a relative parallax of 10^6.15^+/-0.18mas and determined a correction of 0.50+/-0.05mas to absolute parallax, leading to a distance of 9.38+/-0.03pc. We excluded at 3{sigma} confidence the presence of a companion to 2M1821+14 down to a mass ratio of 0.1 (~5M_Jupiter_) with a period of 50-1000d and a separation of 0.1-0.7au. The accurate parallax allowed us to estimate the age and mass of 2M1821+14 of 120-700Myr and 0.049^+0.014^_-0.024_M_{sun}_, thus confirming its intermediate age and substellar mass. We complement our study with a parallax and proper motion catalogue of 587 stars (i'=~15.5-22) close to 2M1821+14, used as astrometric references. This study demonstrates submas astrometry with the GTC, a capability applicable for a variety of science cases including the search for extrasolar planets and relevant for future astrometric observations with E-ELT and TMT.

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