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- 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/372/1804
- Title:
- Magnetic fields of chem. peculiar stars
- Short Name:
- J/MNRAS/372/1804
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectropolarimetric observations of 96 chemically peculiar (CP) main-sequence stars have been carried out at the 6-m telescope at the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) with the aim of searching for the presence of stellar magnetic fields. The stars selected for investigation were CP stars known to have strong anomalies in the wavelength region of the continuum flux depression around {lambda} 5200{AA}. This selection was conducted with the aid of low-resolution spectral observations, made with the SAO RAS 1-m telescope, and of published differential photometric data. Magnetic fields have been successfully detected in 72 stars of which only three stars were previously known to have magnetic fields. For two stars, the longitudinal component of the magnetic field B_e_exceeds 5kG: HD178892 - 7.4kG, and HD258686 - 6.7kG. We failed to reliably detect the magnetic field in the other 24 CP stars. These stars are mostly fast rotators, a feature which hampers accurate measurements of B_e_. It is demonstrated in this paper that selecting candidate magnetic stars by considering their photometric indices Z or {Delta}alpha}, or alternatively, by inspecting low-resolution spectra around the {lambda}5200{AA} flux depression, considerably increases the detection rate.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/73.178
- Title:
- Magnetic fields of CP stars (2011)
- Short Name:
- J/other/AstBu/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of measuring longitudinal magnetic fields (B_e_), rotation velocities (v_e_sini), and radial velocities (V_r_) of 92 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2010. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/75.294
- Title:
- Magnetic fields of CP stars (2012)
- Short Name:
- J/other/AstBu/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of measuring longitudinal magnetic fields (Be), rotation velocities (v_esini), and radial velocities (VR) of 163 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2012. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results.
- 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.
37. MDFC Version 10
- ID:
- ivo://CDS.VizieR/II/361
- Title:
- MDFC Version 10
- Short Name:
- II/361
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC) dedicated to long-baseline interferometry at mid-infrared wavelengths (3-13um). It gathers data for half a million stars, i.e. nearly all the stars of the Hipparcos-Tycho catalogue whose spectral type is reported in the SIMBAD data base. We cross-match 26 data bases to provide basic information, binarity elements, angular diameter, magnitude and flux in the near and mid-infrared, as well as flags that allow us to identify the potential calibrators. The catalogue covers the entire sky with 465857 stars, mainly dwarfs and giants from B to M spectral types closer than 18kpc. The smallest reported values reach 0.16uJy in L and 0.1uJy in N for the flux, and 2-microarcsec for the angular diameter. We build four lists of calibrator candidates for the L and Nbands suitable with the Very Large Telescope Interferometer (VLTI) sub- and main arrays using the MATISSE instrument. We identify 1621 candidates for L and 44 candidates for N with the Auxiliary Telescopes (ATs), 375 candidates for both bands with the ATs, and 259 candidates for both bands with the Unit Telescopes (UTs). Predominantly cool giants, these sources are small and bright enough to belong to the primary lists of calibrator candidates. In the near future, we plan to measure their angular diameter with 1 per cent accuracy.
- ID:
- ivo://CDS.VizieR/J/PASP/119/994
- Title:
- MIPS 24um calibrators
- Short Name:
- J/PASP/119/994
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the stellar calibrator sample and the conversion from instrumental to physical units for the 24{mu}m channel of the Multiband Imaging Photometer for Spitzer (MIPS). The primary calibrators are A stars, and the calibration factor based on those stars is 4.54x10^-2^MJy/sr/(DN/s), with a nominal uncertainty of 2%. We discuss the data reduction procedures required to attain this accuracy; without these procedures, the calibration factor obtained using the automated pipeline at the Spitzer Science Center is 1.6%+/-0.6% lower. We extend this work to predict 24{mu}m flux densities for a sample of 238 stars that covers a larger range of flux densities and spectral types. We present a total of 348 measurements of 141 stars at 24{mu}m. This sample covers a factor of ~460 in 24{mu}m flux density, from 8.6mJy up to 4.0Jy. We show that the calibration is linear over that range with respect to target flux and background level. The calibration is based on observations made using 3s exposures; a preliminary analysis shows that the calibration factor may be 1% and 2% lower for 10 and 30s exposures, respectively. We also demonstrate that the calibration is very stable: over the course of the mission, repeated measurements of our routine calibrator, HD 159330, show a rms scatter of only 0.4%. Finally, we show that the point-spread function (PSF) is well measured and allows us to calibrate extended sources accurately; Infrared Astronomy Satellite (IRAS) and MIPS measurements of a sample of nearby galaxies are identical within the uncertainties.
- ID:
- ivo://CDS.VizieR/III/149
- Title:
- MK Standard Stars
- Short Name:
- III/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The purpose of the present work is to provide a complete list of MK standard stars, selected from the main papers related to this subject, according to the recommendations of both authors of the MK system. The catalogue provides a list of 963 standard stars, with their spectral type, luminosity, equatorial coordinates, magnitudes, colour index (B-V), and references. The magnitude and colours were taken from Mermillod (1986) UBV Photoelectric Photometry Catalogue (catalog <II/122>). In the cases without observations with the UBV catalogue, the apparent magnitude was taken from the SIMBAD data-base (SIMBAD is described at <http://cdsweb.u-strasbg.fr/Simbad.html>)
- ID:
- ivo://CDS.VizieR/J/A+A/281/817
- Title:
- Model atmospheres for Vega
- Short Name:
- J/A+A/281/817
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
