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3391. Southern reddened luminous stars. I.
ID:
ivo://CDS.VizieR/J/other/SAAOC/15.40
Title:
Southern reddened luminous stars. I.
Short Name:
J/other/SAAOC/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
Stroemgren uvby photometry has been obtained for 270 reddened and very reddened OB stars selected from the Stephenson & Sanduleak (1971) catalogue of Luminous Stars in the Southern Milky Way (LSS), Cat. <III/43>. Corrections have been applied to convert the data as closely as possible to the reddened O stars observed by Crawford (1975PASP...87..481C). Uncorrected and corrected data ar presented in Tables 1 and 3, respectively.
3392. Southern reddened luminous stars. II.
ID:
ivo://CDS.VizieR/J/other/SAAOC/15.53
Title:
Southern reddened luminous stars. II.
Short Name:
J/other/SAAOC/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
H{beta} photometry is given for 263 reddened and very reddened stars from the Stephenson & Sanduleak (1971, Cat. <III/43>) catalogue of Luminous Stars in the Southern Milky Way (LSS). The results are combined with the uvby photometry presented in Paper I to determine reddenings, E(b-y), and distances for the stars and to estimate the spectral types and luminosity classes from derived T_eff_ and M_V_ values.
3393. Southern reddened luminous stars. III.
ID:
ivo://CDS.VizieR/J/other/SAAOC/15.65
Title:
Southern reddened luminous stars. III.
Short Name:
J/other/SAAOC/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
V(RI)C photometry has been obtained for 262 reddened and very reddened stars selected from the Stephenson & Sanduleak (1971, Cat. <III/43>) catalogue of Luminous Stars in the Southern Milky Way (LSS). This photometry, together with data from earlier papers in this series, is used to identify a number of probable variable stars.
3394. Southern red high proper motion objects
ID:
ivo://CDS.VizieR/J/A+A/440/1061
Title:
Southern red high proper motion objects
Short Name:
J/A+A/440/1061
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of spectroscopic follow-up observations for a sample of 71 red objects with high proper motions in the range 0.08-1.14 arcsec/yr as detected using APM and SuperCOSMOS Sky Surveys (SSS) measurements of multi-epoch photographic Schmidt plates. Red objects were selected by combining the photographic BjRI magnitudes with 2MASS near-infrared JHKs magnitudes. Some 50 of the 71 spectroscopically classified objects turn out to be late-type (>M6) dwarfs and in more detail, the sample includes 35 ultracool dwarfs with spectral types between M8 and L2, some previously reported, as well as five M-type subdwarfs, including a cool esdM6 object, SSSPM J0500-5406. Distance estimates based on the spectral types and 2MASS J magnitudes place almost all of the late-type (>M6) dwarfs within 50pc, with 25 objects located inside the 25pc limit of the catalogue of nearby stars. Most of the early-type M dwarfs are located at larger distances of 100-200pc, suggesting halo kinematics for some of them. All objects with Halpha equivalent widths larger than 10 Angstroms have relatively small tangential velocities (<50km/s). Finally, some late-type but blue objects are candidate binaries.
3395. Southern Redshifts Catalogue
ID:
ivo://CDS.VizieR/VII/142A
Title:
Southern Redshifts Catalogue
Short Name:
VII/142A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue provides a "best-estimate" of the heliocentric radial velocities of some 13000 galaxies south of Declination 0 degrees. It is based on over 17000 redshift measurements, from over 200 sources, either published or otherwise made public. Aside from redshift references, each entry includes flags as to whether the velocity is from optical or radio observations, or both, as well as an indication of the nature of any optical emission lines. Galaxies with velocities beyond 75000 km/s are not included. All entries have been made interactively, by one person (A.P.F.). The interaction was necessary because different investigators may use different names, quote slightly different positions, and obtain slightly different velocities for the same galaxy. Thus duplicate entries for the same galaxy are avoided (although a few may inevitably be included).
3396. Southern spiral galaxies scaleheights
ID:
ivo://CDS.VizieR/J/A+AS/126/503
Title:
Southern spiral galaxies scaleheights
Short Name:
J/A+AS/126/503
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on Peng's method (1988A&A...206...18P), we obtain scaleheights of 486 southern spiral galaxies, the images of which are taken from the Digitized Sky Survey at Xinglong Station of Beijing Astronomical Observatory. The fitted spiral arms of 70 galaxies are compared with their images to get their optimum inclinations. The scaleheights of other 416 ones are listed in Table 1 in Appendix. After compiling and analyzing the data, we find some statistical correlations. The most interesting results are that a flatter galaxy is bluer and looks brighter, and galaxies become flatter along the Hubble sequence Sab-Scd.
3397. South Galactic cap MCT blue objects
ID:
ivo://CDS.VizieR/J/AJ/119/241
Title:
South Galactic cap MCT blue objects
Short Name:
J/AJ/119/241
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results for the south Galactic cap region of the Montreal-Cambridge-Tololo survey of blue subluminous stars are presented. This region overlaps the 840 deg^2^ region studied almost three decades ago by Slettebak & Brundage (1971AJ.....76..338S). We present a list of equatorial coordinates, photographic photometry, and spectroscopic identifications, as well as finding charts, for 188 blue objects [(U-B)_pg_<=-0.6] brighter than B_pg_=16.5 in this area. Completeness of the survey and comparisons with other similar efforts are discussed.
3398. Space photometry of the Be stars nu Pup
ID:
ivo://CDS.VizieR/J/A+A/620/A145
Title:
Space photometry of the Be stars nu Pup
Short Name:
J/A+A/620/A145
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometry of the bright Be star {nu} Puppis. The observations were obtained with the Solar Mass Ejection Imager (SMEI) and BRITE-Constellation satellites. Several closely but probably not perfectly evenly spaced frequencies are found that are attributed to nonradial pulsations.
3399. Space telescope RM project. III. NGC 5548 LCs
ID:
ivo://CDS.VizieR/J/ApJ/821/56
Title:
Space telescope RM project. III. NGC 5548 LCs
Short Name:
J/ApJ/821/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ground-based optical photometric monitoring data for NGC5548, part of an extended multiwavelength reverberation mapping campaign. The light curves have nearly daily cadence from 2014 January to July in nine filters (BVRI and ugriz). Combined with ultraviolet data from the Hubble Space Telescope and Swift, we confirm significant time delays between the continuum bands as a function of wavelength, extending the wavelength coverage from 1158{AA} to the z band (~9160{AA}). We find that the lags at wavelengths longer than the V band are equal to or greater than the lags of high-ionization-state emission lines (such as HeII{lambda}1640 and {lambda}4686), suggesting that the continuum-emitting source is of a physical size comparable to the inner broad-line region (BLR). The trend of lag with wavelength is broadly consistent with the prediction for continuum reprocessing by an accretion disk with {tau}{propto}{lambda}^4/3^. However, the lags also imply a disk radius that is 3 times larger than the prediction from standard thin-disk theory, assuming that the bolometric luminosity is 10% of the Eddington luminosity (L=0.1L_Edd_). Using optical spectra from the Large Binocular Telescope, we estimate the bias of the interband continuum lags due to BLR emission observed in the filters. We find that the bias for filters with high levels of BLR contamination (~20%) can be important for the shortest continuum lags and likely has a significant impact on the u and U bands owing to Balmer continuum emission.
3400. Space telescope RM project. II. Swift data
ID:
ivo://CDS.VizieR/J/ApJ/806/129
Title:
Space telescope RM project. II. Swift data
Short Name:
J/ApJ/806/129
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent intensive Swift monitoring of the Seyfert 1 galaxy NGC 5548 yielded 282 usable epochs over 125 days across six UV/optical bands and the X-rays. This is the densest extended active galactic nucleus (AGN) UV/optical continuum sampling ever obtained, with a mean sampling rate <0.5 day. Approximately daily Hubble Space Telescope UV sampling was also obtained. The UV/optical light curves show strong correlations (r_max_=0.57-0.90) and the clearest measurement to date of interband lags. These lags are well-fit by a {tau}{propto}{lambda}^4/3^ wavelength dependence, with a normalization that indicates an unexpectedly large disk radius of ~0.35+/-0.05lt-day at 1367{AA}, assuming a simple face-on model. The U band shows a marginally larger lag than expected from the fit and surrounding bands, which could be due to Balmer continuum emission from the broad-line region as suggested by Korista and Goad. The UV/X-ray correlation is weaker (r_max_<0.45) and less consistent over time. This indicates that while Swift is beginning to measure UV/optical lags in general agreement with accretion disk theory (although the derived size is larger than predicted), the relationship with X-ray variability is less well understood. Combining this accretion disk size estimate with those from quasar microlensing studies suggests that AGN disk sizes scale approximately linearly with central black hole mass over a wide range of masses.