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301. The GSH Binary Survey
ID:
ivo://CDS.VizieR/J/AN/338/61
Title:
The GSH Binary Survey
Short Name:
J/AN/338/61
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since 2009 the Grossschwabhausen binary survey is carried out at the University Observatory Jena. This new imaging survey uses available time slots during photometric monitoring campaigns, caused by non-photometric weather conditions, which often exhibit a good atmospheric seeing. The goal of the project is to obtain current relative astrometric measurements of binary systems, that are listed in the Washington Visual Double Star Catalog. In this paper we characterize the target sample of the survey, describe the imaging observations, the astrometric measurements including the astrometric calibration, and present relative astrometric measures of all binaries, which could be obtained in the course of the survey, so far.
302. The large TNO 2002 TC302
ID:
ivo://CDS.VizieR/J/A+A/639/A134
Title:
The large TNO 2002 TC302
Short Name:
J/A+A/639/A134
Date:
21 Oct 2021
Publisher:
CDS
Description:
On 28th January 2018, the large Trans-Neptunian Object 2002 TC_302_ occulted a m_v_~15.3 star with designation 593-005847 in the UCAC4 stellar catalog, corresponding to Gaia source 130957813463146112. Twelve positive occultation chords were obtained from Italy, France, Slovenia and Switzerland. Also, four negative detections were obtained near the north and south limbs. This represents the best observed stellar occultation by a TNO other than Pluto in terms of the number of chords published thus far. From the twelve chords, an accurate elliptical fit to the instantaneous projection of the body can be obtained, compatible with the near misses. The resulting ellipse has major and minor axes of 543+/-18km and 460+/-11km, respectively, with a position angle of 3+/-1 degrees for the minor axis. This information, combined with rotational light curves obtained with the 1.5-m telescope at Sierra Nevada Observatory and the 1.23-m telescope at Calar Alto observatory, allows us to derive possible three-dimensional shapes and density estimations for the body based on hydrostatic equilibrium assumptions. The effective diameter in equivalent area is around 84km smaller than the radiometrically derived diameter using thermal data from Herschel and Spitzer Space Telescopes. This might indicate the existence of an unresolved satellite of up to ~300km in diameter, to account for all the thermal flux, although the occultation and thermal diameters are compatible within their error bars given the considerable uncertainty of the thermal results. The existence of a potential satellite also appears to be consistent with other ground-based data presented here. From the effective occultation diameter combined with absolute magnitude measurements we derive a geometric albedo of 0.147+/-0.005, which would be somewhat smaller if 2002 TC_302_ has a satellite. The best occultation light curves do not show any signs of ring features or any signatures of a global atmosphere.
303. The OB association LH 58
ID:
ivo://CDS.VizieR/J/AJ/108/1256
Title:
The OB association LH 58
Short Name:
J/AJ/108/1256
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present CCD photometry and spectroscopy for stars in Lucke-Hodge 58, an isolated OB association in the Large Magellanic Cloud (LMC) northwest of 30 Doradus. The photometric catalog contains 839 stars with UBV magnitudes complete to V~19. We have obtained spectra and classified 35 stars; combined with previous published spectral types, we find 22 O-type stars. The earliest type is O3-4 V, and there are three WR stars in the association. The slope of the initial mass function, Gamma=-1.7+/-0.3, is in good agreement with other LMC associations. The presence of several evolved supergiants with masses about 15-25M_{sun}_ suggests that some star formation took place as early as 10 million years ago, but the majority of stars formed coevally within the past few million years.
304. The SSRS2 Sample
ID:
ivo://CDS.VizieR/J/AJ/108/1987
Title:
The SSRS2 Sample
Short Name:
J/AJ/108/1987
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we continue our investigation on the isophotal nature, accuracy, and uniformity of the magnitude system adopted in the Southern Sky Redshift Survey extension (SSRS2). Extending our earlier work, we examine galaxies in the equatorial region, primarily in the declination range -17.5 deg <= Dec. <= 0 deg, over a large range of right ascension, covering the southern and northern Galactic caps. For this purpose, we have obtained CCD isophotal magnitudes in the B and R bands for 265 galaxies of different morphological types. Using this larger sample we confirm our earlier claim that the m(SSRS2) magnitudes are very nearly the magnitude measured within the isophote mu_B = 26 mag/arcsec^2, with a dispersion of about 0.30 mag. The relative zero-point offset between our m(SSRS2) magnitudes and CCD photometry is -0.02 mag from all data we have obtained. However, we detect a variation of the zero-point across different regions of the sky of +/- 0.10 mag for regions at large angular separations. We also estimate that the zero-point offset between the m(SSRS2) and Zwicky systems is relatively small (~0.10 mag), which should allow us to combine the data from the SSRS2 and the CfA2 Redshift Survey.
305. The Ursa Major cluster. I.
ID:
ivo://CDS.VizieR/J/AJ/112/2471
Title:
The Ursa Major cluster. I.
Short Name:
J/AJ/112/2471
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Ursa Major Cluster has received remarkably little attention, although it is as near as the Virgo Cluster and contains a comparable number of H I-rich galaxies. In this paper, criteria for group membership are discussed and data are presented for 79 galaxies identified with the group. Of these, all 79 have been imaged at B,R,I bands with CCDs, 70 have been imaged at K' with a HgCdTe array detector, and 70 have been detected in the H I 21 cm line. A complete sample of 62 galaxies brighter than M_B=-16.5 is identified. Images and gradients in surface brightness and color are presented at a common linear scale. As has been seen previously, the galaxies with the reddest global colors are reddest at the centers and get bluer at large radii. However, curiously, among the galaxies with the bluest global colors there are systems with very blue cores that get redder at large radii.
306. The young cluster IC 348.
ID:
ivo://CDS.VizieR/J/ApJ/497/736
Title:
The young cluster IC 348.
Short Name:
J/ApJ/497/736
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD photometry in BVRI was obtained for about 260 stars in and around IC 348, and multiobject spectroscopy for 80 of these. A somewhat larger region was surveyed for stars having H{alpha} in emission; over 110 emission-line stars brighter than about R=19 were discovered. Because H{alpha}emission could be detected to a limit near W=3{AA}, division into weak-line (WTTSs) and classical T Tauri stars (CTTSs) was possible on purely spectroscopic grounds. There is a steep rise in the number of emission-line stars below W(H{alpha})=10{AA}; the proportion of WTTSs to CTTSs in the area surveyed is 58:51. ROSAT detected only about 58% of the spectroscopic WTTSs and about 65% of the CTTSs, although these numbers are sensitive to the survey thresholds. The bulk of the ages of about 100 stars, read off the theoretical tracks of D'Antona & Mazzitelli (1994ApJS...90..467D), range between about 0.7 and 12Myr, but the emission-line stars, which are most likely to be members of IC 348, have a mean age of 1.3Myr. Allowance for unresolved binaries would increase this somewhat, but there is a firm upper limit at 2.95Myr. There is no indication that the ages of the emission-line stars depend upon W(H{alpha}): the IC 348 WTTSs as a population are not systematically older than the CTTSs, but there is a tendency for the WTTSs to be concentrated toward the center of IC 348, while the CTTSs are more widely distributed. There is a scattering of emission-H{alpha} stars over the entire area surveyed. There are too many to be explained as low-mass members of an earlier generation of star formation in Per OB2 or as foreground dMe stars. The mass frequency function, based on some 125 stars fitted to theoretical tracks, rises from 1.5M_{sun}_; to about 0.2M_{sun}_;, with a slope very much like that of the Scalo initial mass function. The optical cluster IC 348 radius is about 4.0', or 0.37pc. The total mass of optically detectable stars in this volume is 57M_{sun}_;, while the mean space density is about 520 stars/pc^3^. The amount of interstellar material remaining within the cluster is small in comparison. Star formation in the Per OB2/IC 348 region cannot be characterized by one unique age; it appears that stars have been forming in the region now occupied by the association for 10-20Myr.
307. Time-series photometry of IC 348
ID:
ivo://CDS.VizieR/J/MNRAS/462/2396
Title:
Time-series photometry of IC 348
Short Name:
J/MNRAS/462/2396
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present long-term photometric observations of the young open cluster IC 348 with a baseline time-scale of 2.4yr. Our study was conducted with several telescopes from the Young Exoplanet Transit Initiative (YETI) network in the Bessell R band to find periodic variability of young stars. We identified 87 stars in IC 348 to be periodically variable; 33 of them were unreported before. Additionally, we detected 61 periodic non-members of which 41 are new discoveries. Our wide field of view was the key to those numerous newly found variable stars. The distribution of rotation periods in IC 348 has always been of special interest. We investigate it further with our newly detected periods but we cannot find a statistically significant bimodality. We also report the detection of a close eclipsing binary in IC 348 composed of a low-mass stellar component (M>~0.09M_{sun}_) and a K0 pre-main sequence star (M~2.7M_{sun}_). Furthermore, we discovered three detached binaries among the background stars in our field of view and confirmed the period of a fourth one.
308. Times of maxima for 23 delta Scuti stars
ID:
ivo://CDS.VizieR/J/PASP/133/H4201
Title:
Times of maxima for 23 delta Scuti stars
Short Name:
J/PASP/133/H4201
Date:
17 Jan 2022 00:25:09
Publisher:
CDS
Description:
The multi-color CCD photometric study of 27 delta Scuti stars is presented. By using approximately three years of photometric observations, we obtained the times of maxima and magnitude changes during the observation time interval for each star. The ephemeris of our delta Scuti star was calculated based on the Markov Chain Monte Carlo (MCMC) method using the observed times of maxima and the period of star' oscillations. We used the Gaia EDR3 parallaxes to calculate the luminosities and also the absolute magnitudes of these delta Scuti stars. The fundamental physical parameters of all studied stars, such as mass and radius, were estimated. We determined the pulsation modes of the stars based on the pulsation constants. Moreover, the period-luminosity relation of delta Scuti stars was investigated and discussed. Then, by using a machine learning classification, new P-L relations for fundamental and overtone modes are presented.
309. Times of minima for 18 LMC eclipsing binaries
ID:
ivo://CDS.VizieR/J/AJ/150/183
Title:
Times of minima for 18 LMC eclipsing binaries
Short Name:
J/AJ/150/183
Date:
21 Oct 2021
Publisher:
CDS
Description:
New CCD observations for 13 eccentric eclipsing binaries from the Large Magellanic Cloud were carried out using the Danish 1.54 m telescope located at the La Silla Observatory in Chile. These systems were observed for their times of minimum and 56 new minima were obtained. These are needed for accurate determination of the apsidal motion. Besides that, in total 436 times of minimum were derived from the photometric databases OGLE and MACHO. The O - C diagrams of minimum timings for these B-type binaries were analyzed and the parameters of the apsidal motion were computed. The light curves of these systems were fitted using the program PHOEBE, giving the light curve parameters. We derived for the first time relatively short periods of the apsidal motion ranging from 21 to 107 years. The system OGLE-LMC-ECL-07902 was also analyzed using the spectra and radial velocities, resulting in masses of 6.8 and 4.4 M_{sun}_ for the eclipsing components. For one system (OGLE-LMC-ECL-20112), the third-body hypothesis was also used to describe the residuals after subtraction of the apsidal motion, resulting in a period of about 22 years. For several systems an additional third light was also detected, which makes these systems suspect for triplicity.
310. Times of minima of eclipsing binaries in 2003
ID:
ivo://CDS.VizieR/J/other/IBVS/5502
Title:
Times of minima of eclipsing binaries in 2003
Short Name:
J/other/IBVS/550
Date:
21 Oct 2021
Publisher:
CDS
Description:
Times of minima for a number of neglected eclipsing binaries are presented.

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