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3381. Ks-band light curve of CoRoT-1b
ID:
ivo://CDS.VizieR/J/ApJ/707/1707
Title:
Ks-band light curve of CoRoT-1b
Short Name:
J/ApJ/707/1707
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the detection in Ks-band of the secondary eclipse of the hot Jupiter CoRoT-1b from time series photometry with the ARC 3.5m telescope at Apache Point Observatory. The eclipse shows a depth of 0.336+/-0.042% and is centered at phase 0.5022^+0.0023^_-0.0027_, consistent with a zero eccentricity orbit (e*cos{omega}=0.0035^+0.0036^_-0.0042_). We perform the first optical to near-infrared multi-band photometric analysis of an exoplanet's atmosphere and constrain the reflected and thermal emissions by combining our result with the recent 0.6, 0.71, and 2.09um secondary eclipse detections by Snellen et al. (2009Natur.459..543S), Gillon et al. (2009, J/A+A/506/359), and Alonso et al. (2009A&A...501L..23A). Comparing the multi-wavelength detections to state-of-the-art radiative-convective chemical-equilibrium atmosphere models, we find the near-infrared fluxes difficult to reproduce. The closest blackbody-based and physical models provide the following atmosphere parameters: a temperature T=2460^+80^_-160_K; a very low Bond albedo A_B_=0.000^+0.081^_-0.000_; and an energy redistribution parameter P_n_=0.1, indicating a small but nonzero amount of heat transfer from the day to nightside. The best physical model suggests a thermal inversion layer with an extra optical absorber of opacity {kappa}_e_=0.05cm^2^/g, placed near the 0.1 bar atmospheric pressure level. This inversion layer is located 10 times deeper in the atmosphere than the absorbers used in models to fit mid-infrared Spitzer detections of other irradiated hot Jupiters.
3382. Ks-band magnitudes of the K20 sample
ID:
ivo://CDS.VizieR/J/A+A/392/395
Title:
Ks-band magnitudes of the K20 sample
Short Name:
J/A+A/392/395
Date:
21 Oct 2021
Publisher:
CDS
Description:
The K20 survey is an ESO VLT optical and near-infrared spectroscopic survey aimed at obtaining spectral information and redshifts of a complete sample of about 550 objects to K_s_<=20.0 over two independent fields with a total area of 52arcmin^2^. In this paper we discuss the scientific motivation of such a survey, we describe the photometric and spectroscopic properties of the sample, and we release the K_s_-band photometric catalog. Extensive simulations showed that the sample is photometrically highly complete to K_s_=20. The observed galaxy counts and the R-K_s_ color distribution are consistent with literature results. We observed spectroscopically 94% of the sample, reaching a spectroscopic redshift identification completeness of 92% to K_s_<=20.0 for the observed targets, and of 87% for the whole sample (i.e. counting also the unobserved targets). Deep spectroscopy was complemented with multi-band deep imaging in order to derive tested and reliable photometric redshifts for the galaxies lacking of spectroscopic redshifts. The results show a very good agreement between the spectroscopic and the photometric redshifts with <z_(spe)_-z_(phot)_>=0.01 and with a dispersion of {sigma}_({Delta}z)_=0.09. Using both the spectroscopic and the photometric redshifts, we reached an overall redshift completeness of about 98%. The size of the sample, the redshift completeness, the availability of high quality photometric redshifts and multicolor spectral energy distributions make the K20 survey database one of the most complete samples available to date for constraining the currently competing scenarios of galaxy formation and for a variety of other galaxy evolution studies.
3383. Ks-band observations of WASP-33b
ID:
ivo://CDS.VizieR/J/A+A/550/A54
Title:
Ks-band observations of WASP-33b
Short Name:
J/A+A/550/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
In recent years, day-side emission from about a dozen hot Jupiters has been detected through ground-based secondary eclipse observations in the near-infrared. These near-infrared observations are vital for determining the energy budgets of hot Jupiters, since they probe the planet-spectral energy distribution near its peak. The aim of this work is to measure the Ks -band secondary eclipse depth of WASP-33b, the first planet discovered to transit an A-type star. This planet receives the highest level of irradiation of all transiting planets discovered to date. Furthermore, its host-star shows pulsations and is classified as a low-amplitude delta-Scuti. As part of our GROUnd-based Secondary Eclipse (GROUSE) project we have obtained observations of two separate secondary eclipses of WASP-33b in the Ks-band using the LIRIS instrument on the William Herschel Telescope (WHT). The telescope was significantly defocused to avoid saturation of the detector for this bright star (K~7.5). To increase the stability and the cadence of the observations, they were performed in staring mode. We collected a total of 5100 and 6900 frames for the first and the second night respectively, both with an average cadence of 3.3 seconds. On the second night the eclipse is detected at the 12-sigma level, with a measured eclipse depth of 0.244_-020_^+0.027^%. This eclipse depth corresponds to a brightness temperature of 3270_-160^+115^K. The measured brightness temperature on the second night is consistent with the expected equilibrium temperature for a planet with a very low albedo and a rapid re-radiation of the absorbed stellar light. For the other night the short out-of-eclipse baseline prevents good corrections for the stellar pulsations and systematic effects, which makes this dataset unreliable for eclipse depth measurements. This demonstrates the need of getting a sufficient out-of-eclipse baseline.
3384. Ks light curve of 299 SMC new Cepheids
ID:
ivo://CDS.VizieR/J/MNRAS/459/1687
Title:
Ks light curve of 299 SMC new Cepheids
Short Name:
J/MNRAS/459/1687
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present K_s_-band light curves for 299 Cepheids in the Small Magellanic Cloud (SMC) of which 288 are new discoveries that we have identified using multi-epoch near-infrared photometry obtained by the VISTA survey of the Magellanic Clouds system (VMC). The new Cepheids have periods in the range from 0.34 to 9.1d and cover the magnitude interval 12.9<=<K_s_><=17.6mag. Our method was developed using variable stars previously identified by the optical microlensing survey OGLE. We focus on searching new Cepheids in external regions of the SMC for which complete VMC K_s_-band observations are available and no comprehensive identification of different types of variable stars from other surveys exists yet.
3385. Ks luminosity of AGB stars in LMC clusters
ID:
ivo://CDS.VizieR/J/ApJ/777/82
Title:
Ks luminosity of AGB stars in LMC clusters
Short Name:
J/ApJ/777/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of K_s_-band luminosity evolution of the asymptotic giant branch (AGB) population in simple stellar systems using star clusters in the Large Magellanic Cloud (LMC). We determine physical parameters of LMC star clusters including center coordinates, radii, and foreground reddenings. Ages of 83 star clusters are derived from isochrone fitting with the Padova models, and those of 19 star clusters are taken from the literature. The AGB stars in 102 star clusters with log(age)=7.3-9.5 are selected using near-infrared color-magnitude diagrams based on Two Micron All Sky Survey photometry. Then we obtain the K_s_-band luminosity fraction of AGB stars in these star clusters as a function of ages. The K_s_-band luminosity fraction of AGB stars increases, on average, as age increases from log(age)~8.0, reaching a maximum at log(age)~8.5, and it decreases thereafter. There is a large scatter in the AGB luminosity fraction for given ages, which is mainly due to stochastic effects. We discuss this result in comparison with five simple stellar population models. The maximum K_s_-band AGB luminosity fraction for bright clusters is reproduced by the models that expect the value of 0.7-0.8 at log(age)=8.5-8.7. We discuss the implication of our results with regard to the study of size and mass evolution of galaxies.
3386. Ks photometry of LMC RR Lyrae
ID:
ivo://CDS.VizieR/J/A+A/502/505
Title:
Ks photometry of LMC RR Lyrae
Short Name:
J/A+A/502/505
Date:
21 Oct 2021
Publisher:
CDS
Description:
RR Lyrae variable stars are the primary Population II distance indicator. Likewise, the LMC constitutes a key step in the extragalactic distance scale. By combining near-IR photometry and spectroscopically measured metallicities for a homogeneous sample of 50 RR Lyr stars in the Large Magellanic Cloud (LMC), we investigate the metallicity dependence of the period-luminosity relation in the near-infrared (IR), use the newly derived relations to re-derive the distance to the LMC, and compare the distance moduli obtained from RR Lyr and red clump stars.
3387. K2 star parameters from Gaia & LAMOST
ID:
ivo://CDS.VizieR/J/ApJS/247/28
Title:
K2 star parameters from Gaia & LAMOST
Short Name:
J/ApJS/247/28
Date:
21 Oct 2021
Publisher:
CDS
Description:
Previous measurements of stellar properties for K2 stars in the Ecliptic Plane Input Catalog (EPIC) largely relied on photometry and proper motion measurements, with some added information from available spectra and parallaxes. Combining Gaia DR2 distances with spectroscopic measurements of effective temperatures, surface gravities, and metallicities from the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) DR5, we computed updated stellar radii and masses for 26838 K2 stars. For 195250 targets without a LAMOST spectrum, we derived stellar parameters using random forest regression on photometric colors trained on the LAMOST sample. In total, we measured spectral types, effective temperatures, surface gravities, metallicities, radii, and masses for 222088 A, F, G, K, and M-type K2 stars. With these new stellar radii, we performed a simple reanalysis of 299 confirmed and 517 candidate K2 planet radii from Campaigns 1-13, elucidating a distinct planet radius valley around 1.9R_{Earth}_, a feature thus far only conclusively identified with Kepler planets, and tentatively identified with K2 planets. These updated stellar parameters are a crucial step in the process toward computing K2 planet occurrence rates.
3388. K survey of Ori A molecular cloud
ID:
ivo://CDS.VizieR/J/AJ/109/709
Title:
K survey of Ori A molecular cloud
Short Name:
J/AJ/109/709
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a 2.2{mu}m (limiting K about 14.5mag) survey of the northern portion of the Orion A molecular cloud. A total of 3548 sources were detected in the 1472arcmin^2^ area surveyed. We detect clustering of 2.2{mu}m sources at the locations of the Trapezium and OMC-2. No strict boundaries for these clusters could be drawn from our data because we find that the entire region surveyed shows an overabundance of sources when compared with background field levels. We find that the form of the observed K luminosity function (KLF) of stars near the Trapezium is consistent with that predicted from a Miller and Scalo (ApJS 41, 513 (1979) IMF, if the age of the cluster is about 1Myr. Away from the Trapezium and the OMC-2, the KLF of stars suggests that either this population contains more low mass stars or that it is older than the Trapezium stars. The survey was carried out using the Ohio State InfraRed Imaging System (OSIRIS) 256x256 HgCdTe array on the Perkins 1.8m telescope in November 1992. In survey mode OSIRIS provides a spatial resolution of 1.50arcsec/pixel; the total field of view of the camera is 6.4arcmin. The telescope was rastered on 4.2arcmin steps to produce a mosaic approximately 39x39arcmin, centered near the Trapezium. A total of 81 K-band images were obtained, each with an exposure time about 3s.
3389. K20 survey: spectroscopic catalogue
ID:
ivo://CDS.VizieR/J/A+A/437/883
Title:
K20 survey: spectroscopic catalogue
Short Name:
J/A+A/437/883
Date:
21 Oct 2021
Publisher:
CDS
Description:
The K20 survey is a near infrared-selected, deep (Ks<20) redshift survey targeting galaxies in two independent regions of the sky, the Chandra Deep Field South and the field around the quasar 0055-2659, for a total area of 52arcmin^2^. The total Ks-selected sample includes 545 objects. Low-resolution (R~300-600) optical spectra for 525 of them have been obtained with the FORS1/FORS2 spectrographs at the ESO/VLT, providing 501 spectroscopic identifications (including 12 type-1 AGN and 45 stars); consequently, we were able to measure redshifts and identify stars in 96% of the observed objects, whereas the spectroscopic completeness with respect to the total photometrically selected sample is 92% (501/545). The K20 survey is therefore the most complete spectroscopic survey of a near infrared-selected sample to date. The K20 survey contains 444 spectroscopically identified galaxies, covering a redshift range of 0.05<z<2.73, with a mean redshift <z>=0.75; excluding the 32 "low-quality" redshifts does not significantly change these values.
3390. K2 & TESS Synergy. I. Parameters & LC, 4 stars
ID:
ivo://CDS.VizieR/J/AJ/160/209
Title:
K2 & TESS Synergy. I. Parameters & LC, 4 stars
Short Name:
J/AJ/160/209
Date:
21 Oct 2021
Publisher:
CDS
Description:
Although the Transiting Exoplanet Survey Satellite (TESS) primary mission observed the northern and southern ecliptic hemispheres, generally avoiding the ecliptic, and the Kepler space telescope during the K2 mission could only observe near the ecliptic, many of the K2 fields extend far enough from the ecliptic plane that sections overlap with TESS fields. Using photometric observations from both K2 and TESS, combined with archival spectroscopic observations, we globally modeled four known planetary systems discovered by K2 that were observed in the first year of the primary TESS mission. Specifically, we provide updated ephemerides and system parameters for K2-114b, K2-167b, K2-237b, and K2-261b. These were some of the first K2 planets to be observed by TESS in the first year and include three Jovian sized planets and a sub-Neptune with orbital periods less than 12 days. In each case, the updated ephemeris significantly reduces the uncertainty in prediction of future times of transit, which is valuable for planning observations with the James Webb Space Telescope and other future facilities. The TESS extended mission is expected to observe about half of the K2 fields, providing the opportunity to perform this type of analysis on a larger number of systems.