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671. Deep OB star population in Carina
ID:
ivo://CDS.VizieR/J/MNRAS/465/1807
Title:
Deep OB star population in Carina
Short Name:
J/MNRAS/465/1807
Date:
21 Oct 2021
Publisher:
CDS
Description:
Massive OB stars are critical to the ecology of galaxies, and yet our knowledge of OB stars in the Milky Way, fainter than V~12, remains patchy. Data from the VST Photometric H-alpha Survey (VPHAS+) permit the construction of the first deep catalogues of blue excess-selected OB stars, without neglecting the stellar field. A total of 14900 candidates with 2MASS cross-matches are blue-selected from a 42 square-degree region in the Galactic longitude range 282{deg}<l<293{deg} Spectral energy distribution fitting is performed on these candidates' combined VPHAS+ u/g/r/i and 2MASS J/H/K magnitudes. This delivers: effective temperature constraints, statistically separating O from early-B stars; high-quality extinction parameters, A_0_ and R_V_ (random errors typically <0.1). The high confidence O-B2 candidates number 5915 and a further 5170 fit to later B spectral type. Spectroscopy of 276 of the former confirms 97% of them. The fraction of emission line stars among all candidate B stars is 7-8%. Greyer (R_V_>3.5) extinction laws are ubiquitous in the region, over the distance range 2.5-3kpc to ~10kpc. Near prominent massive clusters, R_V_ tends to rise, with particularly large and chaotic excursions to R_V_~5 seen in the Carina Nebula. The data reveal a hitherto unnoticed association of 108 O-B2 stars around the O5If+ star LSS 2063 (l=289.77{deg}, b=-1.22{deg}). Treating the OB star scale-height as a constant within the thin disk, we find an orderly mean relation between extinction (A_0_) and distance in the Galactic longitude range, 287.6{deg}<l< 293.5{deg}, and infer the subtle onset of thin-disk warping. A halo around NGC 3603, roughly a degree in diameter, of ~500 O-B2 stars with 4<A_0_(mag)<7 is noted.
672. Deep optical and infrared photometry of Sh2-305
ID:
ivo://CDS.VizieR/J/ApJ/891/81
Title:
Deep optical and infrared photometry of Sh2-305
Short Name:
J/ApJ/891/81
Date:
17 Jan 2022 00:38:10
Publisher:
CDS
Description:
Using our deep optical and near-infrared photometry along with multiwavelength archival data, we here present a detailed study of the Galactic HII region Sh 2-305 to understand the star/star-cluster formation. On the basis of excess infrared emission, we have identified 116 young stellar objects (YSOs) within a field of view of ~18.5'x18.5' around Sh 2-305. The average age, mass, and extinction (AV) for this sample of YSOs are 1.8Myr, 2.9M_{sun}_, and 7.1mag, respectively. The density distribution of stellar sources along with minimal spanning tree calculations on the location of YSOs reveals at least three stellar subclusterings in Sh 2-305. One cluster is seen toward the center (i.e., Mayer 3), while the other two are distributed toward the north and south directions. Two massive O-type stars (VM2 and VM4; ages ~5Myr) are located at the center of the Sh 2-305 HII region. The analysis of the infrared and radio maps traces the photon-dominant regions (PDRs) in Sh 2-305. The association of the younger generation of stars with the PDRs is also investigated in Sh2-305. This result suggests that these two massive stars might have influenced the star formation history in Sh 2-305. This argument is also supported by the calculation of various pressures driven by massive stars, the slope of the mass function/K-band luminosity function, star formation efficiency, fraction of Class I sources, and mass of the dense gas toward the subclusterings in Sh 2-305.
673. Deep spectroscopy of Abell 85
ID:
ivo://CDS.VizieR/J/MNRAS/458/1590
Title:
Deep spectroscopy of Abell 85
Short Name:
J/MNRAS/458/1590
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new deep spectroscopic catalogue for Abell 85, within 3.0x2.6Mpc^2^ and down to M_r_~M_r_^*^+6. Using the Visible Multi-Object Spectrograph at the Very Large Telescope and the AutoFiber 2 at the William Herschel Telescope, we obtained almost 1430 new redshifts for galaxies with m_r_<=21mag and <{mu}_e,r_><=24mag/arcsec^2^. These redshifts, together with Sloan Digital Sky Survey Data Release 6 and NASA/IPAC Extragaalctic Database spectroscopic information, result in 460 confirmed cluster members. This data set allows the study of the luminosity function (LF) of the cluster galaxies covering three orders of magnitudes in luminosities. The total and radial LFs are best modelled by a double Schechter function. The normalized LFs show that their bright (M_r_<=-21.5) and faint (M_r_>=-18.0) ends are independent of clustercentric distance and similar to the field LFs unlike the intermediate luminosity range (-21.5<=M_r_<=-18.0). Similar results are found for the LFs of the dominant types of galaxies: red, passive, virialized and early-infall members. On the contrary, the LFs of blue, star forming, non-virialized and recent-infall galaxies are well described by a single Schechter function. These populations contribute to a small fraction of the galaxy density in the innermost cluster region. However, in the outskirts of the cluster, they have similar densities to red, passive, virialized and early-infall members at the LF faint end. These results confirm a clear dependence of the colour and star formation of Abell 85 members in the cluster centric distance.
674. Deep UVBRI photometry in IC 348
ID:
ivo://CDS.VizieR/J/A+A/324/549
Title:
Deep UVBRI photometry in IC 348
Short Name:
J/A+A/324/549
Date:
21 Oct 2021
Publisher:
CDS
Description:
Table3 contains UBVRI-CCD photometry for the 123 observed stars in the nucleus of IC 348 open cluster. Magnitude and colours are given with their corresponding errors. Column "N" gives the number of observations. Spectral types and cross-identifications with other catalogues are given in note file. Table5 contains adopted reddening solution for the brightest members in IC 348
675. Deep, wide-field g,i imaging of And XXXI
ID:
ivo://CDS.VizieR/J/ApJ/836/137
Title:
Deep, wide-field g,i imaging of And XXXI
Short Name:
J/ApJ/836/137
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from WIYN pODI imaging of Lacerta I (And XXXI), a satellite dwarf galaxy discovered in the outskirts of the Andromeda galaxy (M31) in Pan-STARRS1 survey data. Our deep, wide-field g,i photometry reaches ~3mag fainter than the photometry in the Pan-STARRS1 discovery paper and allows us to trace the stellar population of Lac I beyond two half-light radii from the galaxy center. We measure a Tip of the Red Giant Branch distance for Lac I of (m-M)_0_=24.44+/-0.11mag (773+/-40kpc, or 264+/-6kpc from M31), which is consistent with the Pan-STARRS1 distance. We use a maximum-likelihood technique to derive structural properties for the galaxy, and find a half-light radius (r_h_) of 3.24+/-0.21' (728+/-47pc), ellipticity ({epsilon}) of 0.44+/-0.03, total magnitude M_V_=-11.4+/-0.3, and central surface brightness {mu}_V,0_=24.8+/-0.3mag/arcsec^2^. We find no H I emission in archival data and set a limit on Lac I's neutral gas mass-to-light ratio of M_HI_/L_V_<0.06M_{sun}_/L_{sun}_, confirming Lac I as a gas-poor dwarf spheroidal galaxy. Photometric metallicities derived from Red Giant Branch stars within 2 r_h_ yield a median [Fe/H] of -1.68+/-0.03, which is more metal-rich than the spectroscopically derived value from Martin+ (2014ApJ...793L..14M). Combining our measured magnitude with this higher metallicity estimate places Lac I closer to its expected position on the luminosity-metallicity relation for dwarf galaxies.
676. DEIMOS 10K spectroscopic survey in COSMOS field
ID:
ivo://CDS.VizieR/J/ApJ/858/77
Title:
DEIMOS 10K spectroscopic survey in COSMOS field
Short Name:
J/ApJ/858/77
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 10718 objects in the COSMOS field, observed through multi-slit spectroscopy with the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II telescope in the wavelength range ~5500-9800{AA}. The catalog contains 6617 objects with high-quality spectra (two or more spectral features), and 1798 objects with a single spectroscopic feature confirmed by the photometric redshift. For 2024 typically faint objects, we could not obtain reliable redshifts. The objects have been selected from a variety of input catalogs based on multi-wavelength observations in the field, and thus have a diverse selection function, which enables the study of the diversity in the galaxy population. The magnitude distribution of our objects is peaked at I_AB_~23 and K_AB_~21, with a secondary peak at K_AB_~24. We sample a broad redshift distribution in the range 0<z<6, with one peak at z~1, and another one around z~4. We have identified 13 redshift spikes at z>0.65 with chance probabilities <4x10^-4^, some of which are clearly related to protocluster structures of sizes >10Mpc. An object-to-object comparison with a multitude of other spectroscopic samples in the same field shows that our DEIMOS sample is among the best in terms of fraction of spectroscopic failures and relative redshift accuracy. We have determined the fraction of spectroscopic blends to about 0.8% in our sample. This is likely a lower limit and at any rate well below the most pessimistic expectations. Interestingly, we find evidence for strong lensing of Ly{alpha} background emitters within the slits of 12 of our target galaxies, increasing their apparent density by about a factor of 4.
677. {Delta}a photometry of CP stars
ID:
ivo://CDS.VizieR/J/A+A/441/631
Title:
{Delta}a photometry of CP stars
Short Name:
J/A+A/441/631
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have summarized all {Delta}a measurements for galactic field stars (1474 objects) from the literature published over more than two decades. These measurements were, for the first time, compiled and homogeneously analyzed. The {Delta}a intermediate band photometric system samples the depth of the 5200{AA} flux depression by comparing the flux at the center with the adjacent regions with bandwidths of 110{AA} to 230{AA}. Because it was slightly modified over the last three decades, we checked for systematic trends for the different measurements but found no correlations whatsoever. The {Delta}a photometric system is most suitable to detecting magnetic chemically peculiar (CP) stars with high efficiency, but is also capable of detecting a small percentage of non-magnetic CP objects. Furthermore, the groups of (metal-weak) lambda Bootis, as well as classical Be/shell stars, can be successfully investigated. In addition, we also analyzed the behaviour of supergiants (luminosity class I and II). On the basis of apparent normal type objects, the correlation of the 3sigma significance limit and the percentage of positive detection for all groups was derived.
678. Delta Scuti stars
ID:
ivo://CDS.VizieR/J/A+AS/144/469
Title:
Delta Scuti stars
Short Name:
J/A+AS/144/469
Date:
21 Oct 2021
Publisher:
CDS
Description:
An extensive and up-dated list of {delta} Sct stars is presented here. More than 500 papers, published during the last few years, have been revised and 341 new variables have been added to our last list, six years ago. This catalogue is intended to be a comprehensive review on the observational characteristics of all the {delta} Sct stars known until now, including stars contained in earlier catalogues together with other new discovered variables, covering information published until January 2000. In summary, 636 variables, 1149 references and 182 individual notes are presented in this new list.
679. Detached eclipsing binaries MITSuME photometry
ID:
ivo://CDS.VizieR/J/A+A/622/A114
Title:
Detached eclipsing binaries MITSuME photometry
Short Name:
J/A+A/622/A114
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of the combined photometric and spectroscopic analysis of three detached eclipsing binaries (DEBs), the secondary components of which are not visible or are very hard to identify in the optical spectra - ASAS J052743-0359.7, ASAS J065134-2211.5, and ASAS J073507-0905.7. The first one is the known visual binary ADS~4022, and we found that it is a quadruple system composed of two spectroscopic binaries, one of which shows eclipses.
680. Detached eclipsing binaries with Gaia parallaxes
ID:
ivo://CDS.VizieR/J/ApJ/872/85
Title:
Detached eclipsing binaries with Gaia parallaxes
Short Name:
J/ApJ/872/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 81 Galactic, detached eclipsing binary stars we investigated the global zero-point shift of their parallaxes with the Gaia Data Release 2 (DR2) parallaxes. The stars in the sample lay in a distance range of 0.04-2kpc from the Sun. The photometric parallaxes {omega}_Phot_ of the eclipsing binaries were determined by applying a number of empirical surface brightness-color (SBC) relations calibrated on optical-infrared colors. For each SBC relation we calculated the individual differences d{varpi}_i_=({varpi}_Gaia_-{varpi}_Phot_)_i_ and then we calculated unweighted and weighted means. As the sample covers the whole sky we interpret the weighted means as the global shifts of the Gaia DR2 parallaxes with respect to our eclipsing binary sample. Depending on the choice of the SBC relation the shifts vary from -0.094 to -0.025mas. The weighted mean of the zero-point shift from all colors and calibrations used is d{omega}=-0.054+/-0.024mas. However, the SBC relations based on (B-K) and (V-K) colors, which are the least reddening dependent and have the lowest intrinsic dispersions, give a zero-point shift of d{omega}=-0.031+/-0.011mas in full agreement with results obtained by Lindegren+ (2018A&A...616A...2L) and Arenou+ (2018A&A...616A..17A). Our result confirms the global shift of Gaia DR2 parallaxes of d{omega}=-0.029mas reported by the Gaia team, but we do not confirm the larger zero-point shift reported by a number of follow-up papers.