- ID:
- ivo://CDS.VizieR/J/AJ/162/224
- Title:
- King 7 Vilnius photometry. II. Extinctions
- Short Name:
- J/AJ/162/224
- Date:
- 15 Mar 2022
- Publisher:
- CDS
- Description:
- Interstellar extinction in two concentric square areas of the sizes 1.25x1.25deg^2^ and 0.2x0.2deg^2^ in the direction of open cluster King7 is investigated applying two-dimensional photometric classification of stars observed in the Vilnius seven-color photometric system down to V=15.5mag (1084 stars) and 19.5mag (584 stars), respectively. The cluster members (284 stars) are identified applying their coordinates, proper motions, and parallaxes taken from the Gaia EDR3 catalog. New parameters of the cluster (distance, diameter, interstellar extinction, and age) are obtained. Photogeometric distances of stars are taken from Bailer-Jones et al. (2021) based on the Gaia parallaxes from EDR3. Physically the cluster is located at the outer edge of the Perseus spiral arm at d=2.74kpc, its diameter is 9.6pc, the age is 175{+/-}25Myr, the earliest stars are of spectral classes B6-B7. The average interstellar extinction A_V_=4.24mag. From the radial velocities of CO and the Galactic rotation curve we estimate distances to the nearby dust clouds TGU H989 P2 and P3 at 650-670pc from the Sun.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/130/2571
- Title:
- KISS H{alpha}-selected survey list 3
- Short Name:
- J/AJ/130/2571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400-7200{AA}. In most cases, the detected emission line is H{alpha}. The current survey list covers the region of the NOAO Deep Wide Field Survey (NDWFS). This survey covers two fields; the first is 3{deg}x3{deg} and located at RA=14h30m, DE=34{deg}30' (B1950.0), and the second is 2.3{deg}x4.0{deg} and centered at RA=2h7m30s, DE=-4{deg}44'. A total area of 19.65deg^2^ is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3deg^-2^). We tabulate accurate coordinates and photometry for each source, as well as estimates of the redshift, emission-line flux, and line equivalent width based on measurements of the digital objective-prism spectra. The properties of the KISS ELGs are examined using the available observational data.
- ID:
- ivo://CDS.VizieR/J/AJ/127/1943
- Title:
- KISS H{alpha} survey list 2
- Short Name:
- J/AJ/127/1943
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey for extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors and is the first purely digital objective-prism survey for emission-line galaxies. Here we present the second list of emission-line galaxy candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200{AA}. In most cases, the detected emission line is H{alpha}. The current survey list covers a 1.6{deg}-wide strip located at {delta}=43{deg}30'(B1950) and spans the right ascension range 11h55m to 16h15m. The survey strip runs through the center of the Bootes void and has enough depth to adequately sample the far side of the void. An area of 65.8deg^2^ is covered. A total of 1029 candidate emission-line objects have been selected for inclusion in the survey list (15.6deg^-2^). We tabulate accurate coordinates and photometry for each source, as well as estimates of the redshift and emission-line flux and equivalent width based on measurements of the digital objective-prism spectra. The properties of the KISS emission-line galaxies are examined using the available observational data. Although the current survey covers only a modest fraction of the total volume of the Bootes void, we catalog at least 12 objects that appear to be located within the void. Only one of these objects has been recognized previously as a void galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJ/829/L9
- Title:
- K2 LC of HD 3167 and Robo-AO image
- Short Name:
- J/ApJ/829/L9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of two super-Earth-sized planets transiting the bright (V=8.94, K=7.07) nearby late G-dwarf HD 3167, using data collected by the K2 mission. The inner planet, HD 3167 b, has a radius of 1.6R_{Earth}_ and an ultra-short orbital period of only 0.96d. The outer planet, HD 3167 c, has a radius of 2.9R_{Earth}_ and orbits its host star every 29.85 days. At a distance of just 45.8+/-2.2pc, HD3167 is one of the closest and brightest stars hosting multiple transiting planets, making HD 3167 b and c well suited for follow-up observations. The star is chromospherically inactive with low rotational line-broadening, ideal for radial velocity observations to measure the planets' masses. The outer planet is large enough that it likely has a thick gaseous envelope that could be studied via transmission spectroscopy. Planets transiting bright, nearby stars like HD 3167 are valuable objects to study leading up to the launch of the James Webb Space Telescope.
- ID:
- ivo://CDS.VizieR/J/ApJ/870/13
- Title:
- K2 light curve alternative analysis of ASASSN-18bt
- Short Name:
- J/ApJ/870/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On 2018 February 4.41, the All-Sky Automated Survey for SuperNovae (ASAS-SN) discovered ASASSN-18bt in the K2 Campaign 16 field. With a redshift of z=0.01098 and a peak apparent magnitude of B_max_=14.31, ASASSN-18bt is the nearest and brightest Supernovae Ia type (SNe Ia) yet observed by the Kepler spacecraft. Here we present the discovery of ASASSN-18bt, the K2 light curve, and prediscovery data from ASAS-SN and the Asteroid Terrestrial-impact Last Alert System. The K2 early-time light curve has an unprecedented 30-minute cadence and photometric precision for an SN Ia light curve, and it unambiguously shows a ~4 day nearly linear phase followed by a steeper rise. Thus, ASASSN-18bt joins a growing list of SNe Ia whose early light curves are not well described by a single power law. We show that a double-power-law model fits the data reasonably well, hinting that two physical processes must be responsible for the observed rise. However, we find that current models of the interaction with a nondegenerate companion predict an abrupt rise and cannot adequately explain the initial, slower linear phase. Instead, we find that existing published models with shallow ^56^Ni are able to span the observed behavior and, with tuning, may be able to reproduce the ASASSN-18bt light curve. Regardless, more theoretical work is needed to satisfactorily model this and other early-time SNe Ia light curves. Finally, we use Swift X-ray nondetections to constrain the presence of circumstellar material (CSM) at much larger distances and lower densities than possible with the optical light curve. For a constant-density CSM, these nondetections constrain {rho}<4.5x10^5^cm^-3^ at a radius of 4x10^15^cm from the progenitor star. Assuming a wind-like environment, we place mass loss limits of dM/dt<8x10^-6^M{sun}/yr for {nu}_w_=100km/s, ruling out some symbiotic progenitor systems. This work highlights the power of well-sampled early-time data and the need for immediate multiband, high-cadence follow-up for progress in understanding SNe Ia.
- ID:
- ivo://CDS.VizieR/J/AJ/155/173
- Title:
- K2 light curve for K2-231
- Short Name:
- J/AJ/155/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We identify a sub-Neptune exoplanet (R_p_=2.5+/-0.2R_{Earth}_) transiting a solar twin in the Ruprecht 147 star cluster (3Gyr, 300pc, [Fe/H]=+0.1dex). The ~81 day light curve for EPIC 219800881 (V=12.71) from K2 Campaign 7 shows six transits with a period of 13.84 days, a depth of ~0.06%, and a duration of ~4hr. Based on our analysis of high-resolution MIKE spectra, broadband optical and NIR photometry, the cluster parallax and interstellar reddening, and isochrone models from PARSEC, Dartmouth, and MIST, we estimate the following properties for the host star: M_*_=1.01+/-0.03M_{sun}_, R_*_=0.95+/-0.03R_{sun}_, and T_eff_=5695+/-50K. This star appears to be single based on our modeling of the photometry, the low radial velocity (RV) variability measured over nearly 10yr, and Keck/NIRC2 adaptive optics imaging and aperture-masking interferometry. Applying a probabilistic mass-radius relation, we estimate that the mass of this planet is M_p_=7+5-3M_{Earth}_, which would cause an RV semi-amplitude of K=2+/-1m/s that may be measurable with existing precise RV facilities. After statistically validating this planet with BLENDER, we now designate it K2-231b, making it the second substellar object to be discovered in Ruprecht 147 and the first planet; it joins the small but growing ranks of 22 other planets and three candidates found in open clusters.
- ID:
- ivo://CDS.VizieR/II/42
- Title:
- K-Line Photometry of A Stars
- Short Name:
- II/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A narrow-band spectrometer, compensated for seeing and transparency variations, has been constructed and used to measure the strength of the calcium K-line (3933.68{AA}) in 146 A-type stars. The observations were made in the spring of 1966 with the No.4 16-inch (40cm) telescope at Kitt Peak National Observatory.
- ID:
- ivo://CDS.VizieR/II/43
- Title:
- K-line photometry of Southern A stars
- Short Name:
- II/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The photoelectric measurements of the strength of the Calcium K-line has been extended by 223 stars of predominantly southern or equatorial declinations which are well distributed in right ascension. This has expanded the existent list to 369 field stars for which a k-index is available, including many more Am stars. All available k-index data for field stars are presented here.
- ID:
- ivo://CDS.VizieR/II/44
- Title:
- K-Line photometry of stars in Population I clusters
- Short Name:
- II/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric photometry of the K-line of calcium has been performed for the A stars of five open clusters (Hyades, Pleiades, IC 2391, IC 2602, and NGC 6475) and one association (Orion). All observations were carried out simultaneously with the field stars measurements in Paper II (II/43), with the 16-inch (40cm) and 36-inch (91cm) telescopes of the Cerro Tololo Inter-American Observatory, between May 1969 and January 1970.
- ID:
- ivo://CDS.VizieR/J/AJ/158/20
- Title:
- K-M stars of class I candidate RSGs in Gaia DR2
- Short Name:
- J/AJ/158/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate individual distances and luminosities of a sample of 889 nearby candidate red supergiants (RSGs) with reliable parallaxes ({omega}/{sigma}_{omega}_>4 and RUWE<2.7) from Gaia Data Release 2 (DR2, Cat. I/345). The sample was extracted from the historical compilation of spectroscopically derived spectral types by Skiff (Cat. B/mk), and consists of K-M stars that are listed with class I at least once. The sample includes well-known RSGs from Humphreys (1978ApJS...38..309H), Elias et al. (1985ApJS...57...91E), Jura & Kleinmann (1990ApJS...73..769J), and Levesque et al. (2005ApJ...628..973L). Infrared and optical measurements from the Two Micron All Sky Survey, Catalog of Infrared Observations (CIO), Midcourse Space Experiment, Wide-field Infrared Survey Explorer, MIPSGAL, Galactic Legacy Infrared Midplane Extraordinaire (GLIMPSE), and The Naval Observatory Merged Astrometric Dataset catalogs allow us to estimate the stellar bolometric magnitudes. We analyze the stars in the luminosity versus effective temperature plane and confirm that 43 sources are highly probably RSGs with M_bol_< -7.1 mag. Of the stars in the sample, 43% have masses >7 M_{sun}_. Another ~30% of the sample consists of giant stars.
