- ID:
- ivo://CDS.VizieR/J/PASP/106/1120
- Title:
- Delta Scuti variables. II. DY Her
- Short Name:
- J/PASP/106/1120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second paper in a series on large-amplitude delta Scuti stars intended to determine Baade-Wesselink radii and luminosities with precision. The first paper (Wilson et al., 1993PASP..105..809W) discussed our method of analysis and its application to EH Librae; in this we discuss the observations and analysis of DY Herculis. Optical and infrared photometry and cross-correlated radial-velocity data have been obtained and analyzed. Fourier representations for the UBVRIJHK light curves and for the radial-velocity curves were used to derive a value for the minimum radius for each of 60 combinations of flux and color index. From these we adopt a mean value for the minimum radius of R_min_=2.77+/-0.20R_{sun}_. When combined with effective temperatures from Breger et al. (1978PASP...90..754B), we find a mean bolometric luminosity of <L_B_>=21.70L_{sun}_ and a mean absolute magnitude of <M_B_>=1.41. The radial excursion is 0.149R_{sun}_. We use the same procedure to improve our results for EH Librae, deriving R_min_ for each of 42 combinations of flux and color index, and obtain mean values of R_min_=2.62+/-0.19R_{sun}_, <L_B_>=24.56L_{sun}_ and <M_B_>=1.27.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/136/525
- Title:
- DeltaV photometry of visual double stars
- Short Name:
- J/A+AS/136/525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present angular separations, position angles and {Delta}V instrumental magnitude differences of 83 visual double stars with angular separations around two arcseconds. Our observations were made by means of a CCD detector attached to the Kryonerion 1.2m telescope. 12 of them are common proper motion stars and their components should therefore be stars of common origin.
- ID:
- ivo://CDS.VizieR/VII/234
- Title:
- DENIS catalog of galaxies
- Short Name:
- VII/234
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new, extended and improved version of the provisional I-band catalog of DENIS galaxies. Galaxies not cross-identified with already known galaxies have been visually controlled using the DSS1 images and, occasionally, the coordinates were remeasured. The typical accuracy of coordinates is about 2". The typical error on I-band magnitude is about 0.2mag. The final catalog gives the most common names, the J2000 coordinates, the I-band magnitude, the diameter, the axis ratio and the position angle for about 43000 galaxies. It covers roughly 67% of the southern hemisphere. It is homogeneously sampled up to I=14.5 mag. The data are also available via the LEDA database.
- ID:
- ivo://CDS.VizieR/II/228A
- Title:
- DENIS Catalogue toward Magellanic Clouds (DCMC)
- Short Name:
- II/228A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first version of a complete near-IR point source catalogue towards the Magellanic Clouds extracted from the data obtained with the DEep Near Infraread Survey of the Southern Sky (DENIS). The catalogue covers an area of 19.87x16 square degrees centered on (05:27:20-69:00:00) for the Large Magellanic Cloud (LMC), and 14.7x10 square degrees centered on (01:02:40-73:00:00) for the Small Magellanic Cloud (SMC). It contains the sources detected in at least 2 of the 3 photometric bands I (Gunn-i centered at 0.8{mu}m), J (centered at 1.25{mu}m), and K_s_ (centered at 2.15{mu}m). The spatial resolution is 1" in I and 3" in the J and K bands, and the limiting magnitudes are I=18, J=16 and K_s_=14. 70% of the detected sources are real members of the Magellanic Clouds, and consist mainly of red giants, asymptotic giant branch stars and supergiants.
- ID:
- ivo://CDS.VizieR/J/A+A/363/62
- Title:
- DENIS galaxies around 16h15m -30deg
- Short Name:
- J/A+A/363/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From a visual inspection of J and K images obtained within the Deep Near Infrared Survey (DENIS) we detected 37 noteworthy galaxies near the galactic plane (|b|<15{deg}). Most of these galaxies are yet uncatalogued. They have either a large dimension (more than 1arcmin in J-band) or a position very close to the galactic plane (|b|<3{deg}). Some of these galaxies are simply not visible on the Digitized Sky Survey. Among them 15 galaxies are suspected to be spirals and could be detected from HI observations. Several large galaxies near the assumed position of the Great Attractor suggests that a concentration of galaxies may be present around the equatorial position: {alpha}_2000_=16h15m, {delta}_2000_=-30{deg}. An inspection of this field from the Digitized Sky Survey and from available 2MASS data confirms the presence of extragalactic structures.
- ID:
- ivo://CDS.VizieR/J/A+A/387/1
- Title:
- DENIS galaxies behind the Milky Way
- Short Name:
- J/A+A/387/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search has been undertaken at Lyon Observatory to identify, by eye, galaxy candidates at galactic latitudes lower than +/-15 degrees on the DENIS J and K-band images. This paper presents a list of 2028 objects that were serendipitously detected throughout the DENIS survey. Cross-identification with galaxy entries in the LEDA Database has been performed. Comparison with the second release of the 2MASS survey led to a satisfactory agreement of J band magnitudes (std. dev.=0.3mag). The distribution of galaxy candidates along the Galactic Plane shows a concentration near the galactic longitude l=305deg. As a by product of this inspection of J and K images some interesting galactic objects were found (star clusters and nebulae).
- ID:
- ivo://CDS.VizieR/J/A+A/401/959
- Title:
- 35 DENIS late-M dwarfs between 10 and 30pc
- Short Name:
- J/A+A/401/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper reports updated results on our systematic mining of the DENIS database (<B/denis>) for nearby very cool M-dwarfs (M6V-M8V, 2.0=<I-J=<3.0, photometric distance within 30pc), initiated by Phan-Bao et al. (2001, Cat. <J/A+A/380/590>, hereafter Paper I). We use M dwarfs with well measured parallaxes (HIP, GCTP,...) to calibrate the DENIS (M_I_, I-J) colour-luminosity relationship. The resulting distance error for single dwarfs is about 25%. Proper motions, as well as B and R magnitudes, were measured on archive Schmidt plates for those stars in the DENIS database that meet the photometric selection criteria. We then eliminate the giants by a Reduced Proper Motion cutoff, which is significantly more selective than a simple proper motion cutoff. It greatly reduces the selection bias against low tangential velocity stars, and results in a nearly complete sample. Here we present new data for 62 red dwarf candidates selected over 5700 square degrees in the DENIS database. 26 of those originate in the 2100 square degrees analysed in Paper I, with improved parameters here, and 36 were found in 3600 additional square degrees. 25 of those are new nearby dwarfs. In addition we cross-identified the NLTT and DENIS catalogues to find 15 similar stars, in parts of the sky not yet covered by the colour-selected search. We present distance and luminosity estimates for these 15 stars, 10 of which are newly recognized nearby dwarfs. A similar search in Paper I produced 4 red dwarf candidates, and we have thus up to now identified a total of 35 new nearby late-M dwarfs.
- ID:
- ivo://CDS.VizieR/J/A+A/380/590
- Title:
- 30 DENIS late-M dwarfs between 15 and 30pc
- Short Name:
- J/A+A/380/590
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 30 new nearby (d<30pc) red dwarf candidates, with estimated spectral types M6 to M8. 26 were directly selected from the DENIS database (<B/denis>), and another 4 were first extracted from the LHS catalogue (<I/87>) and cross-identified with a DENIS counterpart. Their proper motions were measured on the MAMA measuring machine from plates spanning 13 to 48 years, and are larger than 0.1arcsec/yr, ruling out the possibility that they are giants. Their distances were estimated from the DENIS colours and IR colour-magnitude relations and range between 15 and 30pc.
- ID:
- ivo://CDS.VizieR/J/A+A/441/653
- Title:
- 32 DENIS nearby red dwarfs
- Short Name:
- J/A+A/441/653
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectra of 36 nearby star candidates and 3 red giant candidates, identified in the DENIS database. 32 of the dwarf candidates are nearby red dwarfs, with spectral types from M5.5 to M8.5. Out of 11 targets with low proper motion (mu<0.1arcsec/yr) but a Reduced Proper Motion above an inclusive threshold, 9 are red dwarfs. The 4 contaminants are all reddened F-K main sequence stars, and could have been eliminated by checking for small well-known high latitude molecular clouds. These stars might be of interest as probes of interstellar absorption. For the red dwarfs we derive spectral types and spectroscopic distances, using a new calibration of the PC3 spectral index to absolute magnitudes in the I, J, H and K photometric bands. We confirm 2 new members of the 12 pc volume (2 new M8.5), and one M7.5 NLTT object closer than 10pc; and show that one quarter of the stars with photometric distances under 30pc have too small a proper motion for inclusion in the NLTT catalog.
4330. DENIS new nearby stars
- ID:
- ivo://CDS.VizieR/J/A+A/390/491
- Title:
- DENIS new nearby stars
- Short Name:
- J/A+A/390/491
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new nearby stars extracted from a proper motion catalogue and having a DENIS counterpart. Their distances and spectral type are estimated using the DENIS colours. 107 stars are within 50pc. 31 stars among them have previously measured distances. In addition, 40 stars may enter within the 50pc limit depending on which population they belong to. 6 stars among them have already measured distances. 5 objects, LHS5045, L225-57, LP831-45, LHS1767, and WT792, are probably closer than 15pc, with L225-57 at 9.5pc. Most of these stars are M-type while 4 stars are white dwarfs. 88 M-dwarfs are disc stars, 14 belong to the thick disc and 1 to the spheroid.