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14551. Starbursts in barred spiral galaxies. VI.
ID:
ivo://CDS.VizieR/J/A+A/416/515
Title:
Starbursts in barred spiral galaxies. VI.
Short Name:
J/A+A/416/515
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper reports a study of the effect of a bar on the neutral hydrogen (HI) content of starburst and Seyfert galaxies. We also make comparisons with a sample of "normal" galaxies and investigate how well starburst and Seyfert galaxies follow the fundamental scaling Tully-Fisher (TF) relation defined for normal galaxies. 111 Markarian (Mrk) IRAS galaxies were observed with the Nancay radiotelescope, and HI data were obtained for 80 galaxies, of which 64 are new detections. We determined the (20 and 50%) linewidths, the maximum velocity of rotation and total HI flux for each galaxy. These measurements are complemented by data from the literature to form a sample of Mrk IRAS (74% starburst, 23% Seyfert and 3% unknown) galaxies containing 105 unbarred and 113 barred ones. Barred galaxies have lower total and bias-corrected HI masses than unbarred galaxies, and this is true for both Mrk IRAS and normal galaxies. This robust result suggests that bars funnel the HI gas toward the center of the galaxy where it becomes molecular before forming new stars. The Mrk IRAS galaxies have higher bias-corrected HI masses than normal galaxies. They also show significant departures from the TF relation, both in the B and K bands. The most deviant points from the TF relation tend to have a strong far-infrared luminosity and a low oxygen abundance. These results suggest that a fraction of our Mrk IRAS galaxies are still in the process of formation, and that their neutral HI gas, partly of external origin, has not yet reached a stationary state.
14552. Starbursts luminosities based on PAH
ID:
ivo://CDS.VizieR/J/ApJ/686/127
Title:
Starbursts luminosities based on PAH
Short Name:
J/ApJ/686/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
A summary of starburst luminosities based on polycyclic aromatic hydrocarbon (PAH) features is given for 243 starburst galaxies with 0<z<2.5, observed with the Spitzer Infrared Spectrograph. Luminosity {nu}L_{nu}_(7.7um) for the peak luminosity of the 7.7um PAH emission feature is found to scale as log[{nu}L_{nu}_(7.7{mu}m)]=44.63(+/-0.09)+2.48(+/-0.28)log(1+z) for the most luminous starbursts observed. Empirical calibrations of {nu}L_{nu}_(7.7um) are used to determine bolometric luminosity L_IR_ and the star formation rate (SFR) for these starbursts. The most luminous starbursts found in this sample have logL_IR_=45.4(+/-0.3)+2.5(+/-0.3)log(1+z), in ergs/s, and the maximum star formation rates for starbursts in units of M_{sun}_/yr are log(SFR)=2.1(+/-0.3)+2.5(+/-0.3)log(1+z), up to z=2.5. The exponent for pure luminosity evolution agrees with optical and radio studies of starbursts but is flatter than previous results based in infrared source counts. The maximum star formation rates are similar to the maxima determined for submillimeter galaxies; the most luminous individual starburst included within the sample has logL_IR_=46.9, which gives an SFR=3.4x10^3^M_{sun}/yr. Description: In this paper, we assemble data from 14 different Spitzer/IRS (InfraRed Spectrograph) programs (listed in "Ref" column of table1) to summarize a wide variety of sources having strong PAH spectral features, providing a total of 243 sources.
14553. Star catalogue of Hevelius (1690)
ID:
ivo://CDS.VizieR/J/A+A/516/A29
Title:
Star catalogue of Hevelius (1690)
Short Name:
J/A+A/516/A29
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue by Johannes Hevelius with the positions and magnitudes of 1564 entries was published by his wife Elisabeth Koopman in 1690. We provide a machine-readable version of the catalogue, and briefly discuss its accuracy on the basis of comparison with data from the modern Hipparcos Catalogue. We compare our results with an earlier analysis by Rybka (1984), finding good overall agreement. The magnitudes given by Hevelius correlate well with modern values. The accuracy of his position measurements is similar to that of Brahe, with error distributions with widths of about 2 arcmin for longitudes and latitudes, but with more errors larger than 5 arcmin than expected for a Gaussian distribution. The position accuracy decreases slowly with magnitude. The fraction of stars with position errors larger than a degree is 1.5 per cent, rather smaller than the fraction of 5 per cent in the star catalogue of Brahe.
14554. 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.
14555. 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).
14556. StarCAT: STIS UV echelle spectra of stars
ID:
ivo://CDS.VizieR/J/ApJS/187/149
Title:
StarCAT: STIS UV echelle spectra of stars
Short Name:
J/ApJS/187/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as "stars," recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2Ms. For many of the objects, broad ultraviolet coverage has been achieved by splicing echellegrams taken in two or more FUV (1150-1700{AA}) and/or NUV (1600-3100{AA}) settings. In cases of multiple pointings on conspicuously variable sources, spectra were separated into independent epochs. Otherwise, different epochs were combined to enhance the signal-to-noise ratio (S/N). A post-facto correction to the "calstis" pipeline data sets compensated for subtle wavelength distortions identified in a previous study of the STIS calibration lamps. An internal "fluxing" procedure yielded coherent spectral energy distributions (SEDs) for objects with broadly overlapping wavelength coverage. The best StarCAT material achieves 300m/s internal velocity precision; absolute accuracy at the 1km/s level; photometric accuracy of order 4%; and relative flux precision several times better (limited mainly by knowledge of SEDs of UV standard stars). While StarCAT represents a milestone in the large-scale post-processing of STIS echellegrams, a number of potential improvements in the underlying "final" pipeline are identified.
14557. Star cluster formation in a tidal debris
ID:
ivo://CDS.VizieR/J/A+A/628/A60
Title:
Star cluster formation in a tidal debris
Short Name:
J/A+A/628/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
The formation of globular clusters remains an open debate. Dwarf starburst galaxies are efficient at forming young massive clusters with similar masses as globular clusters and may hold the key to understanding their formation. We study star cluster formation in a tidal debris - including the vicinity of three tidal dwarf galaxies - in a massive gas dominated collisional ring around NGC 5291. These dwarfs have physical parameters which differ significantly from local starbursting dwarfs. They are gas-rich, highly turbulent, have a gas metallicity already enriched up to half-solar, and are expected to be free of dark matter. The aim is to study massive star cluster formation in this as yet unexplored type of environment. We use imaging from the Hubble Space Telescope using broadband filters covering the wavelength range from the near- ultraviolet to the near-infrared. We determine the masses and ages of the cluster candidates by using the spectral energy distribution- fitting code CIGALE, carefully considering age-extinction degeneracy effects on the estimation of the physical parameters. Results. We find that the tidal dwarf galaxies in the ring of NGC 5291 are forming star clusters with an average efficiency of about 40%, comparable to blue compact dwarf galaxies. We also find massive star clusters for which the photometry suggests that they were formed at the very birth of the tidal dwarf galaxies and have survived for several hundred million years. Therefore our study shows that extended tidal dwarf galaxies and compact clusters may be formed simultaneously. In the specific case observed here, the young star clusters are not massive enough to survive for a Hubble time. However one may speculate that similar objects at higher redshift, with higher star formation rate, might form some of the long lived globular clusters.
14558. Star cluster Gaia 1 stars equivalent widths
ID:
ivo://CDS.VizieR/J/A+A/609/A13
Title:
Star cluster Gaia 1 stars equivalent widths
Short Name:
J/A+A/609/A13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Star clusters, particularly those objects in the disk-bulge-halo interface are as yet poorly charted, despite the fact that they carry important information about the formation and the structure of the Milky Way. Here, we present a detailed chemical abundance study of the recently discovered object Gaia 1. Photometry has previously suggested it as an intermediate-age, moderately metal-rich system, although the exact values for its age and metallicity remained ambiguous in the literature. We measured detailed chemical abundances of 14 elements in four red giant members, from high-resolution (R=25000) spectra that firmly establish Gaia 1 as an object associated with the thick disk. The resulting mean Fe abundance is -0.62+/-0.03(stat.)+/-0.10(sys.) dex, which is more metal-poor than indicated by previous spectroscopy from the literature, but it is fully in line with values from isochrone fitting. We find that Gaia 1 is moderately enhanced in the {alpha}-elements, which allowed us to consolidate its membership with the thick disk via chemical tagging. The cluster's Fe-peak and neutron-capture elements are similar to those found across the metal-rich disks, where the latter indicate some level of s-process activity. No significant spread in iron nor in other heavy elements was detected, whereas we find evidence of light-element variations in Na, Mg, and Al. Nonetheless, the traditional Na-O and Mg-Al (anti-)correlations, typically seen in old globular clusters, are not seen in our data. This confirms that Gaia 1 is rather a massive and luminous open cluster than a low-mass globular cluster. Finally, orbital computations of the target stars bolster our chemical findings of Gaia 1's present-day membership with the thick disk, even though it remains unclear which mechanisms put it in that place.
14559. Star cluster properties in five spiral galaxies
ID:
ivo://CDS.VizieR/J/A+A/501/949
Title:
Star cluster properties in five spiral galaxies
Short Name:
J/A+A/501/949
Date:
21 Oct 2021
Publisher:
CDS
Description:
Aims: Our goal is to investigate the formation of star clusters in relatively unperturbed environments. To do this, we studied the five nearby spiral galaxies: NGC 45, NGC 1313, NGC 4395, NGC 5236, and NGC 7793. Methods: We obtained images of the galaxies and their star cluster systems in UBVI using the Advanced Camera for Surveys (ACS) and the Wide Field Planetary Camera 2 (WFPC2) on board the Hubble Space Telescope. From a comparison of the broad-band colours with simple stellar population (SSP) models, we derived individual properties for each galaxy for the clusters such such as masses, ages, and sizes, as well as global star cluster system properties such as the age distribution, luminosity function, and disruption time for clusters. Results. We identified about 600 star cluster candidates in the five galaxies, typically spanning ages from 3.9Myr up to 1Gyr and masses from 10^2^M_{sun}_ up to 10^5^M_{sun}_. We used the cluster age distribution to reconstruct the recent star formation history of each galaxy and observed significant variations from galaxy to galaxy. We went on to derive the luminosity function of the young star clusters and found slopes around {alpha}~-2 (similar to the ones found in previous studies) and the brightest star cluster magnitudes consistent with a random sampling of the luminosity function without involving an upper luminosity cut off. Finally, the sample includes only a handful of old globular clusters in each galaxy from which we derive low globular cluster specific frequencies.
14560. Star Clusters and Associations, Selected Data
ID:
ivo://CDS.VizieR/VII/5A
Title:
Star Clusters and Associations, Selected Data
Short Name:
VII/5A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog is a selection of data on all open clusters extracted from the second, considerably enlarged edition of the "Catalogue of Star Clusters and Associations" edited by Alter, Balazs, and Ruprecht (1970), which includes four parts: Part 1: 1039 open clusters, five moving clusters, and 11 stellar groups; Part 2: 70 OB associations; Part 3: 125 globular clusters; Part 4: 28 extragalactic objects. The catalog includes galactic and equatorial coordinates, name, classification, angular diameter, distance, magnitude and spectral types of the brightest stars, total magnitude, and color excess.

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