- ID:
- ivo://CDS.VizieR/J/AcA/60/91
- Title:
- VI light curves of SMC type II Cepheids
- Short Name:
- J/AcA/60/91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The eighth part of the OGLE-III Catalog of Variable Stars (OIII-CVS) contains type II Cepheids in the Small Magellanic Cloud (SMC). The sample consists of 43 objects, including 17 BL Her, 17 W Vir and 9 RV Tau stars (first examples ever found in the SMC). Seven stars have been classified as peculiar W Vir stars - a recently identified subclass of type II Cepheids. These stars have distinctive light curves, are brighter and bluer than the ordinary W Vir variables. We confirm that a large fraction of the peculiar W Vir stars are members of binary systems.
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- ID:
- ivo://CDS.VizieR/J/A+A/563/A92
- Title:
- VIPERS: galaxy colours and luminosity function
- Short Name:
- J/A+A/563/A92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the evolution of the colour-magnitude relation (CMR) and luminosity function (LF) at 0.4<z<1.3 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) using ~45000 galaxies with precise spectroscopic redshifts down to i'_AB_<22.5 over ~10.32deg^2^ in two fields. From z=0.5 to z=1.3 the LF and CMR are well defined for different galaxy populations and M^*^_B_ evolves by ~1.04(1.09)+/-0.06(0.10) mag for the total (red) galaxy sample. We compare different criteria for selecting early-type galaxies: (1) a fixed cut in rest-frame (U-V) colours, (2) an evolving cut in (U-V) colours, (3) a rest-frame (NUV-r')-(r'-K) colour selection, and (4) a spectral-energy-distribution classification. The completeness and contamination varies for the different methods and with redshift, but regardless of the method we measure a consistent evolution of the red-sequence (RS). Between 0.4<z<1.3 we find a moderate evolution of the RS intercept of {Delta}(U-V)=0.28+/-0.14 mag, favouring exponentially declining star formation (SF) histories with SF truncation at 1.7<=z<=2.3. Together with the rise in the number density of red galaxies by 0.64dex since z=1, this suggests a rapid build-up of massive galaxies (M_*_>10^11^M_{sun}_) and expeditious RS formation over a short period of ~1.5Gyr starting before z=1. This is supported by the detection of ongoing SF in early-type galaxies at 0.9<z<1.0, in contrast with the quiescent red stellar populations of early-type galaxies at 0.5<z<0.6. There is an increase in the observed CMR scatter with redshift, which is two times larger than observed in galaxy clusters and at variance with theoretical model predictions. We discuss possible physical mechanisms that support the observed evolution of the red galaxy population. Our findings point out that massive galaxies have experienced a sharp SF quenching at z~1 with only limited additional merging. In contrast, less-massive galaxies experience a mix of SF truncation and minor mergers which build-up the low- and intermediate-mass end of the CMR.
- ID:
- ivo://CDS.VizieR/J/ApJS/145/65
- Title:
- Virgo intracluster planetary nebula candidates
- Short Name:
- J/ApJS/145/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Intracluster stars - stars outside of individual galaxies - are a sensitive measure of the poorly understood processes of galactic mergers, cluster accretion, and tidal stripping that occur in galaxy clusters. In particular, intracluster planetary nebulae are a useful probe of intracluster light as a whole. We present a catalog of 318 intracluster planetary nebula candidates in the nearby Virgo Cluster of galaxies, taken with the Kitt Peak National Observatory 4m telescope. We detail the automated detection routines developed to search for these candidates and discuss the routines' strengths and weaknesses. We discuss the importance of contamination in the catalog, and the likely causes. We present magnitudes and positions of these candidates, suitable for spectroscopic follow-up observations. Analyses of these candidates are presented in other papers of this series.
- ID:
- ivo://CDS.VizieR/J/AJ/157/171
- Title:
- Visual analysis and demographics of Kepler TTVs
- Short Name:
- J/AJ/157/171
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We visually analyzed the transit timing variation (TTV) data of 5930 Kepler Objects of Interest (KOIs) homogeneously. Using data from Rowe et al. (2014, J/ApJ/784/45) and Holczer et al. (2015, J/ApJ/807/170; 2016, J/ApJS/225/9), we investigated TTVs for nearly all KOIs in Kepler's Data Release 24 catalog. Using TTV plots, periodograms, and phase-folded quadratic plus sinusoid fits, we visually rated each KOI's TTV data in five categories. Our ratings emphasize the hundreds of planets with TTVs that are weaker than the ~200 that have been studied in detail. Our findings are consistent with statistical methods for identifying strong TTVs, though we found some additional systems worth investigation. Between about 3-50 days and 1.3-6 Earth radii, the frequency of strong TTVs increases with period and radius. As expected, strong TTVs are very common when period ratios are near a resonance, but there is not a one-to-one correspondence. The observed planet-by-planet frequency of strong TTVs is only somewhat lower in systems with one or two known planets (7%+/-1%) than in systems with three or more known planets (11%+/-2%). We attribute TTVs to known planets in multitransiting systems but find ~30 cases where the perturbing planet is unknown. Our conclusions are valuable as an ensemble for learning about planetary system architectures and individually as stepping stones toward more-detailed mass-radius constraints. We also discuss Data Release 25 TTVs, investigate ~100 KOIs with transit duration and/or depth variations, and estimate that the Transiting Exoplanet Survey Satellite will likely find only ~10 planets with strong TTVs.
- ID:
- ivo://CDS.VizieR/J/A+A/497/437
- Title:
- V light curves of DI UMa
- Short Name:
- J/A+A/497/437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts. We examined principal parameters of the system to understand peculiarities of DI UMa, and other active cataclysmic variables. Based on precise photometric measurements, temporal light curve behaviour, O-C analysis, and power spectrum analysis, we investigated physical parameters of the system. We found that the period of the supercycle now equals 31.45+/-0.3days. Observations during superoutbursts infer that the period of superhumps equals P_sh_=0.055318(11)days (79.66+/-0.02min). During quiescence, the light curve reveals a modulation of period P_orb_=0.054579(6)days (78.59+/-0.01min), which we interpret as the orbital period of the binary system. The values obtained allowed us to determine a fractional period excess of 1.35+/-0.02%, which is surprisingly small compared to the usual value for dwarf novae (2%-5%). A detailed O-C analysis was performed for two superoutbursts with the most comprehensive coverage. In both cases, we detected an increase in the superhump period with a mean rate of (dP/dt)/P_sh_=4.4(1.0)x10^-5^. Based on these measurements, we confirm that DI UMa is probably a period bouncer, an old system that reached its period minimum a long time ago, has a secondary that became a degenerate brown dwarf, the entire system evolving now toward longer periods. DI UMa is an extremely interesting object because we know only one more active ER UMa star with similar characteristics (IX Dra).
- ID:
- ivo://CDS.VizieR/J/A+AS/135/493
- Title:
- V light curves of PN M2-54
- Short Name:
- J/A+AS/135/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The time-series V-filter photometry of the variable central star of the Planetary Nebula M2-54 is presented.
- ID:
- ivo://CDS.VizieR/J/MNRAS/330/137
- Title:
- VRc observations of LMC long-period red variables
- Short Name:
- J/MNRAS/330/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 146 long-period red variable stars in the Large Magellanic Cloud (LMC) from the three-year Microlensing Observations in Astrophysics (MOA) project data base were analysed. A careful periodic analysis was performed on these stars and a catalogue of their magnitudes, colours, periods and amplitudes is presented. We convert our blue and red magnitudes to K-band values using 19 oxygen-rich stars. A group of red short-period stars separated from the Mira sequence has been found on a (log P,K) diagram. They are located at the short period side of the Mira sequence consistent with the work of Wood & Sebo (1996MNRAS.282..958W). There are two interpretations for such stars; a difference in pulsation mode or a difference in chemical composition. We investigated the properties of these stars together with their colour, amplitude and periodicity. We conclude that they have small amplitudes and less regular variability. They are likely to be higher-mode pulsators. A large scatter has also been found on the long-period side of the (logP,K) diagram. This is possibly a systematic spread given that the blue band of our photometric system covers both standard B and V bands and affects carbon-rich stars.
- ID:
- ivo://CDS.VizieR/J/A+A/420/447
- Title:
- VRI photometry of lensed quasar QSO B2237+0305
- Short Name:
- J/A+A/420/447
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spatially resolved CCD photometry of the Q2237+0305 gravitationally lensed quasar in V, R and I spectral bands from observations with the Maidanak 1.5-m telescope made in 1995-2000 is presented. For each of the four quasar components, - A, B, C and D, - stellar magnitudes for 78 dates in R filter, and for 17 dates in V and I and shown in Tables 4-6. The color indices V-R and V-I for 17 dates during 1995-2000 are also presented (Table 7), which permitted to analyse a behavior of colors of the lensed quasar images in microlensing, and to discover a significant correlation between the color changes and magnitude changes in the sense, that the components tend to become bluer as their brightness increases.
- ID:
- ivo://CDS.VizieR/J/A+A/530/A5
- Title:
- WASP-4b Ks-band detection of thermal emission
- Short Name:
- J/A+A/530/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Secondary eclipses are a powerful tool to measure directly the thermal emission from extrasolar planets, and to constrain their type and physical parameters. We started a project to obtain reliable broad-band measurements of the thermal emission of transiting exoplanets. Ground-based high-cadence near-infrared relative photometry was used to obtain a sub-millimagnitude precision light curve of a secondary eclipse of WASP-4b -- a 1.12M_J_ hot Jupiter on a 1.34-day orbit around G7V star. The data show a clear ~10{sigma} detection of the planet's thermal emission at 2.2{mu}. The calculated thermal emission corresponds to a fractional eclipse depth of 0.185^+0.014^_-0.013_%, with a related brightness temperature in Ks of T_B_=1995+/-40K, centered at Tc=2455102.61162^+0.00071^_-0.00077_HJD. We could set a limit on the eccentricity of e*cos{omega}=0.0027+/-0.0018, compatible with a near-circular orbit. The calculated brightness temperature, and the specific models suggest a highly inefficient redistribution of heat from the day-side to the night-side of the planet, and a consequent emission mainly from the day-side. The high-cadence ground-based technique is capable of detecting the faint signal of the secondary eclipse of extrasolar planets, which makes it a valuable complement to space-based mid-IR observations.
- ID:
- ivo://CDS.VizieR/J/A+A/549/A102
- Title:
- White dwarf cooling sequences
- Short Name:
- J/A+A/549/A102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new diagnostics of white dwarf (WD) cooling sequences and luminosity functions (LFs) in the near-infrared (NIR) bands that will exploit the sensitivity and resolution of future extremely large telescopes. The collision-induced absorption (CIA) of molecular hydrogen causes a clearly defined blue turn-off along the WD (WDBTO) cooling sequences and a bright secondary maximum in the WD LFs. These features are independent of age over a broad age range and are minimally affected by metal abundance. This means that the NIR magnitudes of the WDBTO are very promising distance indicators.
