- ID:
- ivo://CDS.VizieR/J/MNRAS/442/3544
- Title:
- Kinematic tracers in Umbrella galaxy (NGC4651)
- Short Name:
- J/MNRAS/442/3544
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the dynamics of faint stellar substructures around the Umbrella Galaxy, NGC 4651, which hosts a dramatic system of streams and shells formed through the tidal disruption of a nucleated dwarf elliptical galaxy. We elucidate the basic characteristics of the system (colours, luminosities, stellar masses) using multiband Subaru/Suprime-Cam images. The implied stellar mass ratio of the ongoing merger event is ~1:50. We identify candidate kinematic tracers (globular clusters, planetary nebulae, HII regions) and follow up a subset with Keck/DEIMOS (DEep Imaging Multi-object Spectrograph) spectroscopy to obtain velocities. We find that 15 of the tracers are likely associated with halo substructures, including the probable stream progenitor nucleus. These objects delineate a kinematically cold feature in position-velocity phase space. We model the stream using single test particle orbits, plus a rescaled pre-existing N-body simulation. We infer a very eccentric orbit with a period of ~0.35Gyr and turning points at ~2-4 and ~40kpc, implying a recent passage of the satellite through the disc, which may have provoked the visible disturbances in the host galaxy. This work confirms that the kinematics of low surface brightness substructures can be recovered and modelled using discrete tracers - a breakthrough that opens up a fresh avenue for unravelling the detailed physics of minor merging.
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- ID:
- ivo://CDS.VizieR/J/A+A/372/71
- Title:
- King 5 and Berkeley 20 UBVRI photometry
- Short Name:
- J/A+A/372/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multicolour CCD photometry for two poorly studied open clusters (King 5 and Be 20). Photometry for a field near King 5 was also carried out to estimate the contamination by field stars. The colour magnitude diagrams (CMD) of the clusters show a well defined main sequence extending to the limit of the photometry, V~=20mag. The reddening for King 5, estimated from the colour-colour diagram, is ~0.82, whereas that for Be 20 as estimated by comparing theoretical main-sequence (MS) with the observed MS is 0.10. The morphology of the CMDs indicates that these clusters are old. The CMD of Be 20 shows a globular cluster-like horizontal branch. In case of King 5 the comparison of observational CMDs with the standard isochrones of VandenBerg (1985ApJS...58..711V) indicates an apparent discrepancy between the shape of the turnoff and isochrones. The CMDs of King 5 seem to be better understood in terms of stellar models with convective overshoot. The comparison of the CMDs with the stellar models by Bertelli et al. (1985A&A...150...33B) with convective overshoot produces a good fit for a metallicity Z=0.008 and an age of 1Gyr for King 5 and 5Gyr for Be 20. An apparent distance modulus (m-M)=14.0 and 15.1 has been estimated for King 5 and Be 20 respectively. They correspond to a distance of 1900+/-100pc and 9026+/-480pc, respectively. The radial density distribution in King 5 indicates that there is an excess of low mass stars in the outer region of the cluster, whereas the density distribution in Be 20 shows a good fit with the empirical King (1962AJ.....67..471K) model. For both clusters, observations have also been carried out to search for variable stars.
- ID:
- ivo://CDS.VizieR/J/BaltA/19/197
- Title:
- King 7 Vilnius photometry
- Short Name:
- J/BaltA/19/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of CCD photometry in the seven-color Vilnius system for 1549 stars down to V=16mag in a 1.5 square degree field around the cluster King 7, at the Perseus and Camelopardalis border. Using photometric parameters, two-dimensional spectral types, interstellar extinctions and distances for most of the stars are determined.
- 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.
- ID:
- ivo://CDS.VizieR/II/106
- Title:
- Kiso Ultraviolet Catalog (KUV)
- Short Name:
- II/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a list of 1186 ultraviolet-excess objects found during two surveys with the Kiso Schmidt telescope of the Tokyo Astronomical Observatory. The UGR three-image method was used to detect the objects catalogued, which range in blue magnitude from about 10.0 to 18.5. The table contains equatorial positions to an accuracy of about 0.5 seconds of arc (equinox and equator B1950.0, epoch of observation), magnitudes (green of the "three-image [UGR] method"), color indices (as estimated from the enhancement of the U image relative to the G), object codes (white dwarf, QSO, diffuse object, etc.), and alternate designations (in addition to a KUV coordinate designation).
- 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/ApJS/109/45
- Title:
- Kitt Peak galaxy redshift survey
- Short Name:
- J/ApJS/109/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Redshifts, four-band photometry (U B_J_ R_F_ I_N_), and astrometry are presented for faint galaxies in four widely separated fields. We provide the necessary information to enable well-defined, statistically complete subsamples of faint galaxies to be constructed from the master catalog. The redshift survey is 86% and 71% complete to R_F_<=18.5 and R_F<=19, respectively, yielding 328 galaxies with reliable redshifts to R_F_<=19, with a median redshift of 0.142. Adding the galaxies from the fainter statistical sample yields a total of 583 reliable redshifts with a median redshift of 0.202. An additional 156 redshifts in the same fields, but not part of the samples defined here, are also given. Of the 739 galaxy redshifts presented, 212 are for galaxies with R_F_>20.
- 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.
