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301. 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.
302. 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.
303. 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.
304. 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.
305. 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.
306. 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.
307. 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.
308. Mass-luminosity relation
ID:
ivo://CDS.VizieR/J/AJ/106/773
Title:
Mass-luminosity relation
Short Name:
J/AJ/106/773
Date:
21 Oct 2021
Publisher:
CDS
Description:
Mass-luminosity relations determined at infrared wavelengths are presented for stars with masses 1.0 to 0.08 solar masses. Using infrared speckle imaging techniques on a sample of nearby binaries, we have been able to concentrate on the lower main sequence (Mass<=0.5M_sun_), for which an accurate mass-luminosity calibration has remained problematic. In addition, the mass-visual luminosity relation for stars with 2.0>=Mass>=0.08M_sun_ is produced by implementing new photometric relations linking V to JHK wavelengths for the nearby stars, supplemented with eclipsing binary information. These relations predict that objects with masses ~0.08 solar masses have M(K)~=10 and M(V)~=18.
309. M2000: Bordeaux Carte du Ciel zone +11<Dec<+18
ID:
ivo://CDS.VizieR/I/272
Title:
M2000: Bordeaux Carte du Ciel zone +11<Dec<+18
Short Name:
I/272
Date:
21 Oct 2021
Publisher:
CDS
Description:
During four years, systematic observations have been conducted in drift scan mode with the Bordeaux automated meridian circle in the declination band [+11 ; +18]. The resulting astrometric catalog includes about 2 300 000 stars down to the magnitude limit V_M_=16.3. Nearly all stars (96%) have been observed at least 6 times, the catalog being complete down to V_M_=15.4. The median internal standard error in position is about 35mas in the magnitude range 11<V_M_<15, which degrades to about 50mas when the faintest stars are considered. M2000 provides also one band photometry with a median internal standard error of 0.04mag. Comparisons with the Hipparcos and bright part of Tycho-2 catalogs have enabled to estimate external errors in position to be lower than 40mas. In this zone and at epoch 1998, the faint part of Tycho-2 is found to have an accuracy of 116mas in alpha instead of 82mas deduced from the model-based standard errors given in the catalog.
310. MC structure and properties
ID:
ivo://CDS.VizieR/J/A+A/649/A7
Title:
MC structure and properties
Short Name:
J/A+A/649/A7
Date:
22 Feb 2022
Publisher:
CDS
Description:
This work is part of the Gaia Data Processing and Analysis Consortium papers published with the Gaia Early Data Release 3 (EDR3). It is one of the demonstration papers aiming to highlight the improvements and quality of the newly published data by applying them to a scientific case. We use the Gaia EDR3 data to study the structure and kinematics of the Magellanic Clouds. The large distance to the Clouds is a challenge for the Gaia astrometry. The Clouds lie at the very limits of the usability of the Gaia data, which makes the Clouds an excellent case study for evaluating the quality and properties of the Gaia data. The basis of our work are two samples selected to provide a representation as clean as possible of the stars of the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC). The selection used criteria based on position, parallax, and proper motions to remove foreground contamination from the Milky Way, and allowed the separation of the stars of both Clouds. From these two samples we defined a series of subsamples based on cuts in the colour-magnitude diagram; these subsamples were used to select stars in a common evolutionary phase and can also be used as approximate proxies of a selection by age. We compared the Gaia Data Release 2 (DR2) and Gaia EDR3 performances in the study of the Magellanic Clouds and show the clear improvements in precision and accuracy in the new release. We also show that the systematics still present in the data make the determination of the 3D geometry of the LMC a difficult endeavour; this is at the very limit of the usefulness of the Gaia EDR3 astrometry, but it may become feasible with the use of additional external data. We derive radial and tangential velocity maps and global profiles for the LMC for the several subsamples we defined. To our knowledge, this is the first time that the two planar components of the ordered and random motions are derived for multiple stellar evolutionary phases in a galactic disc outside the Milky Way, showing the differences between younger and older phases. We also analyse the spatial structure and motions in the central region, the bar, and the disc, providing new insights into features and kinematics. Finally, we show that the Gaia EDR3 data allows clearly resolving the Magellanic Bridge, and we trace the density and velocity flow of the stars from the SMC towards the LMC not only globally, but also separately for young and evolved populations. This allows us to confirm an evolved population in the Bridge that is slightly shift from the younger population. Additionally, we were able to study the outskirts of both Magellanic Clouds, in which we detected some well-known features and indications of new ones.