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531. Star catalogue of Tycho Brahe (1627)
ID:
ivo://CDS.VizieR/J/A+A/516/A28
Title:
Star catalogue of Tycho Brahe (1627)
Short Name:
J/A+A/516/A28
Date:
21 Oct 2021
Publisher:
CDS
Description:
Tycho Brahe completed his catalogue with the positions and magnitudes of 1004 fixed stars in 1598. This catalogue circulated in manuscript form. Brahe edited a shorter version with 777 stars, printed in 1602, and Kepler edited the full catalogue of 1004 stars, printed in 1627. We provide machine-readable versions of the three versions of the catalogue, describe the differences between them and briefly discuss their accuracy on the basis of comparison with modern data from the Hipparcos Catalogue. We also compare our results with earlier analyses by Dreyer (1916Obs....39..127D, On Tycho Brahe's manual of trigonometry) and Rawlins (1993BAAS...25.1335R, Atmospheric Clarity and Tycho's Fake Stars), finding good overall agreement. The magnitudes given by Brahe correlate well with modern values, his longitudes and latitudes have error distributions with widths of 2-arcmin, with excess numbers of stars with larger errors (as compared to Gaussian distributions), in particular for the faintest stars. Errors in positions larger than about 10-arcmin, which comprise about 15 per cent of the entries, are likely due to computing or copying errors.
532. Star catalogues of Ptolemaios, Ulugh Beg
ID:
ivo://CDS.VizieR/J/A+A/544/A31
Title:
Star catalogues of Ptolemaios, Ulugh Beg
Short Name:
J/A+A/544/A31
Date:
21 Oct 2021
Publisher:
CDS
Description:
In late antiquity and throughout the middle ages, the positions of stars on the celestial sphere were obtained from the star catalogue of Ptolemaios. A catalogue based on new measurements appeared in 1437, with positions by Ulugh Beg, and magnitudes from the 10th-century astronomer al-Sufi. We provide machine-readable versions of these two star catalogues, based on the editions by Toomer (1998) and Knobel (1917), and determine their accuracies by comparison with the modern Hipparcos Catalogue. The magnitudes in the catalogues correlate well with modern visual magnitudes; the indication `faint' by Ptolemaios is found to correspond to his magnitudes 5 and 6. Gaussian fits to the error distributions in longitude/latitude give widths sigma ~27-arcmin/23-arcmin in the range |{Delta}{lambda},{Delta}{beta}|<50-arcmin for Ptolemaios and {sigma}~22-arcmin/18-arcmin\ in Ulugh Beg. Fits to the range |{Delta}{lambda},{Delta}{beta}<100-arcmin gives 10-15 per cent larger widths, showing that the error distributions are broader than gaussians. The fraction of stars with positions wrong by more than 150-arcmin is about 2 per cent for Ptolemaios and 0.1 percent in Ulugh Beg; the numbers of unidentified stars are 1 in Ptolemaios and 3 in Ulugh Beg. These numbers testify to the excellent quality of both star catalogues (as edited by Toomer and Knobel).
533. Star formation in DDO 210 and NGC 3109
ID:
ivo://CDS.VizieR/J/AJ/105/894
Title:
Star formation in DDO 210 and NGC 3109
Short Name:
J/AJ/105/894
Date:
21 Oct 2021
Publisher:
CDS
Description:
The method proposed in Paper I [Tosi et al., AJ, 102, 951 (1991)] to study the star formation histories in nearby irregulars is here applied to the galaxies DDO 210 and NGC 3109. To this purpose we have obtained deep CCD photometry of two regions in DDO 210 and three regions in NGC 3109, reaching V = 24 with the required accuracy of Sigma(V) <= 0.1 mag. Major information on the stellar populations, star formation rates, and initial mass functions of these regions in the last 1 Gyr are derived from the comparison of the observational color-magnitude diagrams and luminosity functions, with the corresponding synthetic diagrams and luminosity functions generated by a numerical simulation code based on stellar evolutionary tracks. In general, for both galaxies we find that in the last 1 Gyr the star formation activity has been rather continuous, possibly occurring in long episodes of moderate activity separated by short quiescent periods. According to our models the metallicity should be fairly low (in the range 0.05 <= Z/Zsun <= 0.5) and the initial mass function exponent in the vicinity of Salpeter's value, i.e., slightly flatter than in the solar neighborhood. The studied regions of NGC 3109 appear to contain different stellar populations (i.e., with slightly different metallicity and star formation histories), whereas those of DDO 210 seem to have fairly similar stellar contents, although for this galaxy the interpretation is more uncertain. As a by-product of our method we find that the distance modulus to DDO 210 should be (m-M)0 approx. 28, which places this galaxy beyond the edge of the Local Group.
534. Star kinematics catalog in 19 Kapteyn's areas
ID:
ivo://CDS.VizieR/J/PAZh/23/931
Title:
Star kinematics catalog in 19 Kapteyn's areas
Short Name:
J/PAZh/23/931
Date:
21 Oct 2021
Publisher:
CDS
Description:
1214 individual measurements of radial velocities made with CORAVEL-type spectrometer (Tokovinin, 1987AZh....64..196T) are presented for 1134 stars in 19 northern Kapteyn's areas. Precise coordinates are given for all these stars. Proper motions of stars are taken from NLTT (Luyten, 1979, Cat. <I/98>), PPM (Roser, Bastian, 1991, Cat. <I/146> and <I/193>), NPM1 (Klemola, Hanson, Jones, 1987, Cat. <I/200>) and Four-million catalog (Kuimov, 1992, In: On the four-million catalog of stars, eds. Izd. MGU, Moscow, P.27.; Glushkova et al., 1996PAZh...22..850G). A list of suspected binary stars and stars with variable radial velocities is also given. Two-dimensional spectral classification for these area is available (Bartaya, 1979AbaOB..51....1B).
535. Star positions in 14 southern galactic clusters
ID:
ivo://CDS.VizieR/J/A+AS/53/181
Title:
Star positions in 14 southern galactic clusters
Short Name:
J/A+AS/53/181
Date:
21 Oct 2021
Publisher:
CDS
Description:
Positions for a total of 3487 stars, scattered over 14 regions, have been determined using the Danish 1.5-m telescope at La Silla. The 14 regions are centred on one of the southern galactic clusters NGC 1981, 2287, 2437, 2451, 2516, 2546, 2547, 2548, 3114, 3532, IC 2391, 2395, 2602 and Trumpler 10. Combining the Ritchey-Chretien reflector optics with a single element Schmidt-type corrector, gives a considerably enlarged flat field (radius about 25 minutes of arc, or 95mm) with stellar images of excellent definition. With the exception of distortion, which can be allowed for, the effect of the primary aberrations is negligible. A frame of reference has been established for each region using ESO Schmidt plates centred on the clusters, each plate containing from 20 to 35 measurable Perth 70 stars. These objects have served for determining positions of some 200 to 400 fainter stars within a central field of 25 minutes of arc radius, covering the corresponding 1.5-m plates. The fainter stars serve as a secondary standard. Based on three 1.5-m plates for each region, taken on different nights, an internal mean error in one plate position in the range 0.030 to 0.048 seconds of arc has been derived.
536. Star positions in the region of alpha Per
ID:
ivo://CDS.VizieR/J/AN/283/109
Title:
Star positions in the region of alpha Per
Short Name:
J/AN/283/109
Date:
21 Oct 2021
Publisher:
CDS
Description:
This file contains 1221 stars observed for spectral type in the field of the alpha Persei cluster. The types were published in the well known proper-motion survey by Heckmann et al. (1956AN....283..109H), and were determined by Wachmann with the equipment and methods used for the Bergedorf selected areas surveys (BSD). In general the brighter HD stars were not observed for spectral type, but most of these have been classified on the MK system by Roman & Morgan (1950ApJ...111..426R) and in later work. Nearly all the stars are included in SIMBAD with the source positions, and most also appear in WEBDA with these data as well. The positions below are nearly all from UCAC2 (for both epoch and equinox J2000), and thus differ by a few arcsec mainly from proper motion, but also from the systematic shift between the FK3 to the ICRS. In general the spectral types are not present in SIMBAD or WEBDA. I worked from Alain Fresneau's compilation for the field, which is based largely on the Heckmann data (Cat. <I/68>). I ran those coordinates into VizieR looking at UCAC2, Tycho-2, and the Fabricius Tycho double-star catalogue (Cat. <I/276>). Coordinates for two crowded stars were obtained from 2MASS. With one exception all the stars were found quite close to the predicted positions. Close pairs are indicated in the notes, as are stars with substantial proper motion (>>0.1"/year).
537. Stars in the Sagittarius Rift
ID:
ivo://CDS.VizieR/J/AJ/130/2701
Title:
Stars in the Sagittarius Rift
Short Name:
J/AJ/130/2701
Date:
21 Oct 2021
Publisher:
CDS
Description:
A magnitude-limited photographic survey of relative proper-motion components and B, V photometry of 1.3x10^6^ stars brighter than apparent B magnitude 14.5+/-0.5 in the fourth Galactic quadrant is converted into a distance-limited survey of 3.26x10^5^ stars up to a distance of 500pc. A streaming motion of 13.5+/-0.5 km/s is detected in 4.1x10^4^ Population I stellar candidates with an orbital perigalactic center located at 6.8<=R<=7.2kpc, with a Sun location Rsol=8.5 kpc. A density perturbation of about 0.1M{sun}/pc^3^ in the Galactic field potential at Ro~6.8kpc is interpreted as resulting from the density wave connected with the Sagittarius-Carina spiral arm. A set of 1.4x10^4^ stars of mass about 1.5+/-0.75 M{sun} identify a pitch angle of 10+/-1{deg} and a migration time from the Sagittarius spiral arm into the greater solar neighborhood of about 35Myr.
538. Stellar dynamics and proper motions in 47Tuc
ID:
ivo://CDS.VizieR/J/ApJS/166/249
Title:
Stellar dynamics and proper motions in 47Tuc
Short Name:
J/ApJS/166/249
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used HST imaging of the central regions of the globular cluster 47 Tucanae (=NGC 104), taken with the WFPC2 and ACS instruments between 1995 and 2002, to derive proper motions and U- and V-band magnitudes for 14366 stars within 100 (about 5 core radii) of the cluster center. This represents the largest set of member velocities collected for any globular cluster. The stars involved range in brightness from just fainter than the horizontal branch of the cluster to more than 2.5mag below the main-sequence turnoff. In the course of obtaining these kinematic data, we also use a recent set of ACS images to define a list of astrometrically calibrated positions (and F475W magnitudes) for nearly 130000 stars in a larger, 3x3 central area. We describe our data reduction procedures in some detail and provide the full position, photometric, and velocity data.
539. Stellar occultation by (541132) Leleakuhonua
ID:
ivo://CDS.VizieR/J/AJ/159/230
Title:
Stellar occultation by (541132) Leleakuhonua
Short Name:
J/AJ/159/230
Date:
21 Oct 2021
Publisher:
CDS
Description:
A stellar occultation by the extreme large-perihelion trans-Neptunian object (541132)-Leleakuhonua (also known by the provisional designation of 2015TG_387_) was predicted by the Lucky Star project and observed with the Research and Education Collaborative Occultation Network (RECON) on 2018-October-20-UT. A single detection and a nearby nondetection provide constraints for the size and albedo. When a circular profile is assumed, the radius is r=110_-10_^+14^km, corresponding to a geometric albedo p_V_=0.21_-0.05_^+0.03^, for an adopted absolute magnitude of HV=5.6, typical of other objects in dynamically similar orbits. The occultation also provides a high-precision astrometric constraint.
540. Stellar population in {rho} Oph cloud core
ID:
ivo://CDS.VizieR/J/ApJ/438/813
Title:
Stellar population in {rho} Oph cloud core
Short Name:
J/ApJ/438/813
Date:
21 Oct 2021
Publisher:
CDS
Description:
This contribution reports the results of an infrared imaging survey aimed at characterizing the stellar populations associated with the three densest star-forming cores in the Ophiuchus molecular cloud complex. The survey has sufficient sensitivity at J, H, and K (at 5{sigma} limits of 16.5, 15.4 and 14.2) to provide a complete census of embedded young stellar objects (YSOs) with masses greater than the hydrogen-burning limit, provided that their ages are less than 3 Myr and that they are obscured by no more than ~18 mag of visual extinction. Our data suggest (1) a large fraction (>70%) of the sources located within the cores are still surrounded by circumstellar disks and/or envelopes; and (2) the shape of the initial mass function for masses, M<1M_sun_, appears to be consistent with that derived from the solar neighborhood. We also report the results of a deeper imaging survey of centimeter continuum sources (14 sources) in these star-forming cores and in the larger Ophiuchus complex (eight sources). A large fraction 11/14) of the radio sources associated with the cores appear to have infrared excesses diagnostic of circumstellar accretion disks and/or infalling circumstellar envelopes. In these cases, the centimeter continuum radiation most likely diagnoses the ionized component of energetic winds or jets which characterize YSOs during the disk accretion phase. By contrast, of the eight radio sources located outside dense cores, only two show infrared excesses. For the sources which lack infrared excesses, the centimeter continuum emission is probably produced by gyrosynchrotron radiation arising in the stellar magnetospheres of weak emission T Tauri stars. There is some evidence that the frequency of binary companions among the sample of centimeter continuum sources in the molecular cores may be higher (by as much as a factor of 3-4) than that among the older, distributed population of young stars in the larger Ophiuchus cloud complex.