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121. Amplitudes of single-mode Cepheids
ID:
ivo://CDS.VizieR/J/A+A/504/959
Title:
Amplitudes of single-mode Cepheids
Short Name:
J/A+A/504/959
Date:
21 Oct 2021
Publisher:
CDS
Description:
The dependence of amplitude on the pulsation period differs from other Cepheid-related relationships. We attempt to revise the period-amplitude (P-A) relationship of Galactic Cepheids based on multi-colour photometric and radial velocity data. Reliable P-A graphs for Galactic Cepheids constructed for the U, B, V, Rc, and Ic photometric bands and pulsational radial velocity variations facilitate investigations of previously poorly studied interrelations between observable amplitudes. The effects of both binarity and metallicity on the observed amplitude, and the dichotomy between short- and long-period Cepheids can both be studied. A homogeneous data set was created that contains basic physical and phenomenological properties of 369 Galactic Cepheids. Pulsation periods were revised and amplitudes were determined by the Fourier method. P-A graphs were constructed and an upper envelope to the data points was determined in each graph. Correlations between various amplitudes and amplitude-related parameters were searched for, using Cepheids without known companions.
122. AMUSING++ nearby galaxy compilation. I. Sample
ID:
ivo://CDS.VizieR/J/AJ/159/167
Title:
AMUSING++ nearby galaxy compilation. I. Sample
Short Name:
J/AJ/159/167
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present here the All-weather MUse Supernova Integral-field of Nearby Galaxies (AMUSING++): the largest compilation of nearby galaxies observed with the Multi Unit Spectroscopic Explorer (MUSE) integral-field spectrograph so far. This collection consists of 635 galaxies from different MUSE projects covering the redshift interval 0.0002<z<0.1. The sample and its main properties are characterized and described here. It includes galaxies of almost all morphological types, with a good coverage in its color-magnitude diagram, within the stellar mass range between 10^8^ and 10^12^M{sun}, and with properties resembling those of a diameter-selected sample. The AMUSING++ sample is, therefore, suitable for studying, with unprecedented detail, the properties of nearby galaxies at global and local scales, providing us with more than 50 million individual spectra. We use this compilation to investigate the presence of galactic outflows. We exploit the use of combined emission-line images to explore the shape of the different ionized components and the distribution along classical diagnostic diagrams to disentangle the different ionizing sources across the optical extension of each galaxy. We use the cross-correlation function to estimate the level of symmetry of the emission lines as an indication of the presence of shocks and/or active galactic nuclei. We uncovered a total of 54 outflows, comprising ~8% of the sample. A large number of the discovered outflows correspond to those driven by active galactic nuclei (~60%), suggesting some bias in the selection of our sample. No clear evidence was found that outflow host galaxies are highly star-forming, and outflows appear to be found within all galaxies around the star-formation sequence.
123. An ALMA survey of ECDFS submillimeter galaxies
ID:
ivo://CDS.VizieR/J/ApJ/788/125
Title:
An ALMA survey of ECDFS submillimeter galaxies
Short Name:
J/ApJ/788/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first photometric redshift distribution for a large sample of 870 {mu}m submillimeter galaxies (SMGs) with robust identifications based on observations with ALMA. In our analysis we consider 96 SMGs in the Extended Chandra Deep Field South, 77 of which have 4-19 band photometry. We model the SEDs for these 77 SMGs, deriving a median photometric redshift of z_phot_=2.3+/-0.1. The remaining 19 SMGs have insufficient photometry to derive photometric redshifts, but a stacking analysis of Herschel observations confirms they are not spurious. Assuming that these SMGs have an absolute H-band magnitude distribution comparable to that of a complete sample of z~1-2 SMGs, we demonstrate that they lie at slightly higher redshifts, raising the median redshift for SMGs to z_phot_=2.5+/-0.2. Critically we show that the proportion of galaxies undergoing an SMG-like phase at z>=3 is at most 35%+/-5% of the total population. We derive a median stellar mass of M_*_=(8+/-1)x10^10^ M_{sun}_, although there are systematic uncertainties of up to 5x for individual sources. Assuming that the star formation activity in SMGs has a timescale of ~100 Myr, we show that their descendants at z~0 would have a space density and M_H_ distribution that are in good agreement with those of local ellipticals. In addition, the inferred mass-weighted ages of the local ellipticals broadly agree with the look-back times of the SMG events. Taken together, these results are consistent with a simple model that identifies SMGs as events that form most of the stars seen in the majority of luminous elliptical galaxies at the present day.
124. Analysis of flares of V1285 Aql
ID:
ivo://CDS.VizieR/J/PASP/123/659
Title:
Analysis of flares of V1285 Aql
Short Name:
J/PASP/123/659
Date:
21 Oct 2021
Publisher:
CDS
Description:
Statistically analysing Johnson UBVR observations of V1285 Aql during the three observing seasons, both activity level and behaviour of the star are discussed in respect to obtained results. We also discuss the variation out-of-flare due to rotational modulation.
125. Analysis of K2 LCs for members of USco & {rho} Oph
ID:
ivo://CDS.VizieR/J/AJ/155/196
Title:
Analysis of K2 LCs for members of USco & {rho} Oph
Short Name:
J/AJ/155/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of K2 light curves (LCs) for candidate members of the young Upper Sco (USco) association (~8 Myr) and the neighboring {rho} Oph embedded cluster (~1 Myr). We establish ~1300 stars as probable members, ~80% of which are periodic. The phased LCs have a variety of shapes which can be attributed to physical causes ranging from stellar pulsation and stellar rotation to disk-related phenomena. We identify and discuss a number of observed behaviors. The periods are ~0.2-30 days with a peak near 2 days and the rapid period end nearing breakup velocity. M stars in the young USco region rotate systematically faster than GK stars, a pattern also present in K2 data for the older Pleiades and Praesepe systems. At higher masses (types FGK), the well-defined period-color relationship for slowly rotating stars seen in the Pleiades and Praesepe systems is not yet present in USco. Circumstellar disks are present predominantly among the more slowly rotating M stars in USco, with few disks in the subday rotators. However, M dwarfs with disks rotate faster on average than FGK systems with disks. For four of these disked M dwarfs, we provide direct evidence for disk locking based on the K2 LC morphologies. Our preliminary analysis shows a relatively mass-independent spin-up by a factor of ~3.5 between USco and the Pleiades, then mass-dependent spin-down between Pleiades and Praesepe.
126. An atlas of UV-to-MIR galaxy SEDs
ID:
ivo://CDS.VizieR/J/ApJS/212/18
Title:
An atlas of UV-to-MIR galaxy SEDs
Short Name:
J/ApJS/212/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the ultraviolet to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, merging galaxies, blue compact dwarfs, and luminous infrared galaxies. We have combined ground-based optical drift-scan spectrophotometry with infrared spectroscopy from Spitzer and Akari with gaps in spectral coverage being filled using Multi-wavelength Analysis of Galaxy Physical Properties spectral energy distribution models. The spectroscopy and models were normalized, constrained, and verified with matched-aperture photometry measured from Swift, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, Spitzer, and Wide-field Infrared Space Explorer images. The availability of 26 photometric bands allowed us to identify and mitigate systematic errors present in the data. Comparison of our spectral energy distributions with other template libraries and the observed colors of galaxies indicates that we have smaller systematic errors than existing atlases, while spanning a broader range of galaxy types. Relative to the prior literature, our atlas will provide improved K-corrections, photometric redshifts, and star-formation rate calibrations.
127. ANDICAM BVRIJHK light curve of Nova V906 Car
ID:
ivo://CDS.VizieR/J/ApJ/899/162
Title:
ANDICAM BVRIJHK light curve of Nova V906 Car
Short Name:
J/ApJ/899/162
Date:
14 Mar 2022 07:11:01
Publisher:
CDS
Description:
We present optical and infrared photometry of the classical nova V906 Car, also known as Nova Car 2018 and ASASSN-18fv, which was discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) on 2018 March 16.32 UT (MJD 58193.0). The nova reached its maximum on MJD 58222.56 at Vmax=5.84{+/-}0.09mag, and had decline times of t_2,V_=26.2days and t_3,V_=33.0days. The data from Evryscope shows that the nova had already brightened to g'~13mag five days before discovery, as compared with its quiescent magnitude of g=20.13{+/-}0.03. The extinction toward the nova, as derived from high-resolution spectroscopy, shows an estimate consistent with foreground extinction to the Carina Nebula of A_V_=1.11_-0.39_^+0.54^. The light curve resembles a rare C (cusp) class nova with a steep decline slope of {alpha}=-3.94 post-cusp flare. From the light-curve decline rate, we estimate the mass of the white dwarf to be MWD=<0.8M{sun}, consistent with M_WD_=0.71_-0.19_^+0.23^ derived from modeling the accretion disk of the system in quiescence. The donor star is likely a K-M dwarf of 0.23-0.43M_{odot}, which is heated by its companion.
128. 2012 and 2017 light curves of asteroid 2012 TC4
ID:
ivo://CDS.VizieR/J/AJ/161/112
Title:
2012 and 2017 light curves of asteroid 2012 TC4
Short Name:
J/AJ/161/112
Date:
21 Oct 2021
Publisher:
CDS
Description:
Asteroid 2012TC4 is a small (~10m) near-Earth object that was observed during its Earth close approaches in 2012 and 2017. Earlier analyses of light curves revealed its excited rotation state. We collected all available photometric data from the two apparitions to reconstruct its rotation state and convex shape model. We show that light curves from 2012 and 2017 cannot be fitted with a single set of model parameters; the rotation and precession periods are significantly different for these two data sets, and they must have changed between or during the two apparitions. Nevertheless, we could fit all light curves with a dynamically self-consistent model assuming that the spin states of 2012TC4 in 2012 and 2017 were different. To interpret our results, we developed a numerical model of its spin evolution in which we included two potentially relevant perturbations: (I) gravitational torque due to the Sun and Earth and (II) radiation torque, known as the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. Despite our model simplicity, we found that the role of gravitational torques is negligible. Instead, we argue that the observed change of its spin state may be plausibly explained as a result of the YORP torque. To strengthen this interpretation, we verify that (I) the internal energy dissipation due to material inelasticity and (II) an impact with a sufficiently large interplanetary particle are both highly unlikely causes of its observed spin state change. If true, this is the first case where the YORP effect has been detected for a tumbling body.
129. A new catalog of HII regions in M31
ID:
ivo://CDS.VizieR/J/AJ/142/139
Title:
A new catalog of HII regions in M31
Short Name:
J/AJ/142/139
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of HII regions in M31. The full disk of the galaxy (~24kpc from the galaxy center) is covered in a 2.2deg^2^ mosaic of 10 fields observed with the Mosaic Camera on the Mayall 4m telescope as part of the Local Group Galaxies survey.
130. A new photo-z method for quasars in Stripe 82
ID:
ivo://CDS.VizieR/J/AJ/154/269
Title:
A new photo-z method for quasars in Stripe 82
Short Name:
J/AJ/154/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new algorithm to estimate quasar photometric redshifts (photo-zs), by considering the asymmetries in the relative flux distributions of quasars. The relative flux models are built with multivariate Skew-t distributions in the multidimensional space of relative fluxes as a function of redshift and magnitude. For 151392 quasars in the SDSS, we achieve a photo-z accuracy, defined as the fraction of quasars with the difference between the photo-z z_p_ and the spectroscopic redshift z_s_, |{Delta}_z_|=|z_s_-z_p_|/(1+z_s_) within 0.1, of 74%. Combining the WISE W1 and W2 infrared data with the SDSS data, the photo-z accuracy is enhanced to 87%. Using the Pan-STARRS1 or DECaLS photometry with WISE W1 and W2 data, the photo-z accuracies are 79% and 72%, respectively. The prior probabilities as a function of magnitude for quasars, stars, and galaxies are calculated, respectively, based on (1) the quasar luminosity function, (2) the Milky Way synthetic simulation with the Besancon model, and (3) the Bayesian Galaxy Photometric Redshift estimation. The relative fluxes of stars are obtained with the Padova isochrones, and the relative fluxes of galaxies are modeled through galaxy templates. We test our classification method to select quasars using the DECaLS g, r, z, and WISE W1 and W2 photometry. The quasar selection completeness is higher than 70% for a wide redshift range 0.5<z<4.5, and a wide magnitude range 18<r<21.5 mag. Our photo-z regression and classification method has the potential to extend to future surveys. The photo-z code will be publicly available.