- ID:
- ivo://CDS.VizieR/J/ApJ/842/42
- Title:
- Improved reddenings for 59 Galactic Cepheids
- Short Name:
- J/ApJ/842/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new photometric method by which improved high-precision reddenings and true distance moduli can be determined to individual Galactic Cepheids once distance measurements are available. We illustrate that the relative positioning of stars in the Cepheid period-luminosity (PL) relation (Leavitt law) is preserved as a function of wavelength. This information then provides a powerful constraint for determining reddenings to individual Cepheids, as well as their distances. As a first step, we apply this method to the 59 Cepheids in the compilation of Fouque et al. Updated reddenings, distance moduli (or parallaxes), and absolute magnitudes in seven (optical through near-infrared) bands are given. From these intrinsic quantities, multiwavelength PL and color-color relations are derived. We find that the V-band period-luminosity-color relation has an rms scatter of only 0.06mag, so that individual Cepheid distances can be measured to 3%, compared with dispersions of 6 to 13% for the one-parameter K through B PL relations, respectively. This method will be especially useful in conjunction with the new accurate parallax sample upcoming from Gaia.
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- ID:
- ivo://CDS.VizieR/J/ApJS/172/663
- Title:
- Infrared observations of the Pleiades
- Short Name:
- J/ApJS/172/663
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We make use of new near- and mid-IR photometry of the Pleiades cluster in order to help identify proposed cluster members. We also use the new photometry with previously published photometry to define the single-star main-sequence locus at the age of the Pleiades in a variety of color-magnitude planes. The new near- and mid-IR photometry extend effectively 2 mag deeper than the 2MASS All-Sky Point Source catalog, and hence allow us to select a new set of candidate very low-mass and substellar mass members of the Pleiades in the central square degree of the cluster. We identify 42 new candidate members fainter than K_s_=14 (corresponding to 0.1M_{sun}_). These candidate members should eventually allow a better estimate of the cluster mass function to be made down to of order 0.04M_{sun}_. We also use new IRAC data, in particular the images obtained at 8um, in order to comment briefly on interstellar dust in and near the Pleiades.
- ID:
- ivo://CDS.VizieR/J/AJ/157/139
- Title:
- Inner Oort cloud survey observations: 2015 TG387
- Short Name:
- J/AJ/157/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Inner Oort cloud objects (IOCs) are trans-Plutonian for their entire orbits. They are beyond the strong gravitational influences of the known planets, yet close enough to the Sun that outside forces are minimal. Here we report the discovery of the third known IOC after Sedna and 2012 VP113, called 2015 TG387. This object has a perihelion of 65+/-1 au and semimajor axis of 1170+/-70 au. The longitude of perihelion angle, {omega}, for 2015 TG387 is between that of Sedna and 2012 VP113 and thus similar to the main group of clustered extreme trans-Neptunian objects (ETNOs), which may be shepherded into similar orbital angles by an unknown massive distant planet called Planet X, or Planet Nine. The orbit of 2015 TG387 is stable over the age of the solar system from the known planets and Galactic tide. When including outside stellar encounters over 4 Gyr, 2015 TG387's orbit is usually stable, but its dynamical evolution depends on the stellar encounter scenarios used. Surprisingly, when including a massive Planet X beyond a few hundred au on an eccentric orbit that is antialigned in longitude of perihelion with most of the known ETNOs, we find that 2015 TG387 is typically stable for Planet X orbits that render the other ETNOs stable as well. Notably, 2015 TG387's argument of perihelion is constrained, and its longitude of perihelion librates about 180{deg} from Planet X's longitude of perihelion, keeping 2015 TG387 antialigned with Planet X over the age of the solar system.
- ID:
- ivo://CDS.VizieR/J/ApJ/659/1138
- Title:
- Intermediate-redshift spiral galaxies Vmax
- Short Name:
- J/ApJ/659/1138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Combining resolved optical spectroscopy with panoramic HST imaging, we study the dynamical properties of spiral galaxies as a function of position across two intermediate-redshift clusters, and we compare the cluster population to field galaxies in the same redshift range. By modeling the observed rotation curves, we derive maximal rotation velocities for 40 cluster spirals and 37 field spirals, yielding one of the largest matched samples of cluster and field spirals at intermediate redshift. We construct the Tully-Fisher (TF) relation in both V and Ks bands, and find that the cluster Tully-Fisher relation exhibits significantly higher scatter than the field relation, in both V and Ks bands.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A131
- Title:
- Ionized Gas Kinematics in MaNGA AGN
- Short Name:
- J/A+A/659/A131
- Date:
- 17 Mar 2022 00:05:59
- Publisher:
- CDS
- Description:
- Feedback from active galactic nuclei (AGN) in general seems to play an important role in the evolution of galaxies, although the impact of AGN winds on their host galaxies is still pending on detailed analysis. We analyse the kinematics of a sample of 170 AGN host galaxies as compared to those of a matched control sample of nonactive galaxies from the MaNGA survey in order to characterise and estimate the extents of the Narrow Line Region (NLR) and of the kinematically disturbed region (KDR) by the AGN. We define the observed NLR radius (r_NLR,o_) as the farthest distance from the nucleus within which both [OIII]/H{beta} and [NII]/H{alpha} ratios fall in the AGN region of the BPT diagram and the H equivalent width is required to be larger than 3.0{AA}. The extent of the KDR (rKDR,o) is defined as the distance from the nucleus within which the AGN hosts galaxies shows a more disturbed gas kinematics than the control galaxies. The AGN [OIII]5007 luminosity ranges from 10^39^ to 10^41^erg/s, and the kinematics derived from the [OIII] line profiles reveal that, on average, the most luminous AGN (L[OIII]>3.8x10^40^erg/s) possess higher residual difference between the gaseous and stellar velocities and velocities dispersion than their control galaxies in all the radial bins. Spatially resolved NLR's and KDR's were found in 55 and 46 AGN host galaxies, with corrected radii 0.2<r_KDR,c_<2.3kpc and 0.4<r_NLR,c_<10.1kpc, with a relation between the two given by logr_KDR,c_=(0.53+/-0.12)logr_NLR,c_+(1.07+/-0.22), respectively. On average, the extension of the KDR corresponds to about 30 per cent of that of the NLR. Assuming that the KDR is due to an AGN outflow, we have estimated ionised gas mass outflow rates that range between 10^-5^ and ~1M_{sun}_/yr, and kinetic powers that range from 10^34^ to 10^40^erg/s. Comparing the power of the AGN ionised outflows with the AGN luminosities, they are always below the 0.05 LAGN model threshold for having a an important feedback effect on their respective host galaxies. The mass outflow rates (and power) of our AGN sample correlate with their luminosities, populating the lowest AGN luminosity range of the correlations previously found for more powerful sources.
- ID:
- ivo://CDS.VizieR/J/A+A/502/883
- Title:
- I photometry of very low mass ONC stars
- Short Name:
- J/A+A/502/883
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Rotational studies at a variety of ages and masses are important for constraining the angular momentum evolution of young stellar objects (YSO). Of particular interest are the very low mass (VLM) stars and brown dwarfs (BDs), because of the significant lack of known rotational periods in that mass range. We aim to extend previous studies well down into the substellar regime, providing for the first time information on rotational periods for a large sample of young VLM stars and BDs. This extensive rotational period study of YSOs in the 1 Myr old Orion Nebula Cluster (ONC) is based on a deep photometric monitoring campaign using the Wide Field Imager (WFI) camera on the ESO/MPG 2.2m telescope on La Silla, Chile. Time series data was obtained with about 95 data points spread over 19 nights. Accurate I-band photometry of 2908 stars was obtained within a magnitude range of 13 to 21mag, i.e. extending three magnitudes deeper than previous studies in the ONC. Two different power spectral analysis techniques were used to search for periodic variability. In addition, the chi^2^ variability test was used for the detection of irregular variables.
- ID:
- ivo://CDS.VizieR/J/ApJ/795/22
- Title:
- Iron abundance of Terzan 5 stars
- Short Name:
- J/ApJ/795/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new determinations of the iron abundance for 220 stars belonging to the stellar system Terzan 5 in the Galactic bulge. The spectra have been acquired with FLAMES at the Very Large Telescope of the European Southern Observatory and DEIMOS at the Keck II Telescope. This is by far the largest spectroscopic sample of stars ever observed in this stellar system. From this data set, a subsample of targets with spectra unaffected by TiO bands was extracted and statistically decontaminated from field stars. Once combined with 34 additional stars previously published by our group, a total sample of 135 member stars covering the entire radial extent of the system has been used to determine the metallicity distribution function of Terzan 5. The iron distribution clearly shows three peaks: a super-solar component at [Fe/H]=~0.25 dex, accounting for ~29% of the sample, a dominant sub-solar population at [Fe/H]=~-0.30 dex, corresponding to ~62% of the total, and a minor (6%) metal-poor component at [Fe/H]=~-0.8 dex. Such a broad, multi-modal metallicity distribution demonstrates that Terzan 5 is not a genuine globular cluster but the remnant of a much more complex stellar system.
- ID:
- ivo://CDS.VizieR/J/ApJ/790/73
- Title:
- Iron and alpha abundance of RGBs in M31 satellites
- Short Name:
- J/ApJ/790/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present alpha to iron abundance ratios for 226 individual red giant branch stars in nine dwarf galaxies of the Andromeda (M31) satellite system. The abundances are measured from the combined signal of Mg, Si, Ca, and Ti lines in Keck/DEIMOS medium-resolution spectra. This constitutes the first large sample of alpha abundance ratios measured in the M31 satellite system. The dwarf galaxies in our sample exhibit a variety of alpha abundance ratios, with the average values in each galaxy ranging from approximately solar ([{alpha}/Fe] ~ + 0.0) to alpha-enhanced ([{alpha}/Fe] ~ + 0.5). These variations do not show a correlation with internal kinematics, environment, or stellar density. We confirm radial gradients in the iron abundance of two galaxies out of the five with sufficient data (NGC 185 and And II). There is only tentative evidence for an alpha abundance radial gradient in NGC 185. We homogeneously compare our results to the Milky Way classical dwarf spheroidals, finding evidence for wider variation in average alpha abundance. In the absence of chemical abundances for the M31 stellar halo, we compare to the Milky Way stellar halo. A stellar halo comprised of disrupted M31 satellites is too metal-rich and inconsistent with the Milky Way halo alpha abundance distribution even if considering only satellites with predominantly old stellar populations. The M31 satellite population provides a second system in which to study chemical abundances of dwarf galaxies and reveals a wider variety of abundance patterns than the Milky Way.
- ID:
- ivo://CDS.VizieR/J/MNRAS/384/1583
- Title:
- JHK light curves of RR Lyr
- Short Name:
- J/MNRAS/384/1583
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present infrared JHK time series photometry of the variable star RR Lyr, that allows us to construct the first complete and accurate infrared light curves for this star. The derived mean magnitudes are <J>=6.74+/-0.02, <H>=6.60+/-0.03 and <K>=6.50+/-0.02. The <K> magnitude is used to estimate the reddening, the mass, the mean luminosity and the temperature of this variable star. The use of these RR Lyr data provides a more accurate absolute calibration of the P-L_K_-[Fe/H] relation, and a distance modulus (m-M)0=18.48+/-0.11 to the globular cluster Reticulum in the Large Magellanic Cloud.
- ID:
- ivo://CDS.VizieR/VII/254
- Title:
- Kazarian galaxies catalog
- Short Name:
- VII/254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The entire KG (KG) catalog is presented which combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the STScI Digitized Sky Survey (DSS) of Jpg(blue), Fpg(red) and Ipg(NIR) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. We provide accurate coordinates, morphological type, spectral and activity classes, blue apparent diameters, axial ratios, position angles, red, blue and NIR apparent magnitudes, as well as counts of neighboring objects in a circle of radius 50kpc from centers of KG. Special attention was paid to the individual descriptions of the galaxies in the original Kazarian lists, which clarified many cases of misidentifications of the objects, particularly among interacting systems. The total number of individual Kazarian objects in the database is now 706. We also include the redshifts which are now available for 404 galaxies, and the 2MASS infrared magnitudes for 598 KG. The database also includes extensive notes, which summarize information about the membership of KG in different systems of galaxies, and about revised activity classes and redshifts. An atlas of several interesting subclasses of KG is also presented.
