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3271. K-band AO imaging in COSMOS deep field
ID:
ivo://CDS.VizieR/J/A+A/468/937
Title:
K-band AO imaging in COSMOS deep field
Short Name:
J/A+A/468/937
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of an imaging program of distant galaxies (z~0.8) at high spatial resolution (~0.1") aiming at studying their morphological evolution. We observed 7 fields of 1'x1' with the NACO Adaptive Optics system (VLT) in Ks (2.16{mu}m) band with typical V~14 guide stars and 3h integration time per field. Observed fields are selected within the COSMOS survey area, in which multi-wavelength photometric and spectroscopic observations are ongoing. High angular-resolution K-band data have the advantage of probing old stellar populations in the rest-frame, enabling a determination of galaxy morphological types unaffected by recent star formation, which are more closely linked to the underlying mass than classical optical morphology studies (HST). Adaptive optics on ground based telescopes is the only method today for obtaining such a high resolution in the K-band, but it suffers from limitations since only small fields are observable and long integration times are necessary.
3272. K-band images of star-forming regions
ID:
ivo://CDS.VizieR/J/other/PASA/26.439
Title:
K-band images of star-forming regions
Short Name:
J/other/PASA/26.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep, wide-field, Ks-band (2.14-micron) images towards 87 southern massive star formation regions traced by methanol maser emission. Using point-spread function fitting, we generate 2.14-micron point source catalogues (PSCs) towards each of the regions. For the regions between 10{deg}<l<350{deg} and |b|<1, we match the 2.14-micron sources with the GLIMPSE point source catalogue to generate a combined 2.14- to 8.0-micron point source catalogue. We provide this data for the astronomical community to utilise in studies of the stellar content of embedded clusters.
3273. K-band light curve of GRS 1915+105
ID:
ivo://CDS.VizieR/J/ApJ/657/409
Title:
K-band light curve of GRS 1915+105
Short Name:
J/ApJ/657/409
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of 7 years of K-band monitoring of the low-mass X-ray binary GRS 1915+105. Positive correlations between the infrared flux and the X-ray flux and X-ray hardness are demonstrated. Analysis of the frequency spectrum shows that the orbital period of the system is P_orb_=30.8+/-0.2days. The phase and amplitude of the orbital modulation suggests that the modulation is due to the heating of the face of the secondary star. We also report another periodic signature between 31.2 and 31.6days, most likely due to a superhump resonance. From the superhump period we then obtain a range for the mass ratio of the system, 0.05<q<0.12.
3274. K-band luminosity function from 2MASX
ID:
ivo://CDS.VizieR/J/ApJ/702/955
Title:
K-band luminosity function from 2MASX
Short Name:
J/ApJ/702/955
Date:
21 Oct 2021
Publisher:
CDS
Description:
Differential Ks-band luminosity functions (LFs) are presented for a complete sample of 1613 nearby bright galaxies segregated by visible morphology. The LF for late-type spirals follows a power law that rises toward low luminosities whereas the LFs for ellipticals, lenticulars, and bulge-dominated spirals are peaked and decline toward both higher and lower luminosities. Each morphological type (E, S0, S0/a-Sab, Sb-Sbc, Sc-Scd) contributes approximately equally to the overall Ks-band luminosity density of galaxies in the local universe. Type averaged bulge/disk ratios are used to subtract the disk component leading to the prediction that the Ks-band LF for bulges is bimodal with ellipticals dominating the high luminosity peak, comprising 60% of the bulge luminosity density in the local universe with the remaining 40% contributed by lenticulars and the bulges of spirals. Overall, bulges contribute 30% of the galaxy luminosity density at Ks in the local universe with spiral disks making up the remainder. If bulge luminosities indicate central black hole (BH) masses, then our results predict that the BH mass function is also bimodal.
3275. K-band Luminosity Function of Field Galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/312/557
Title:
K-band Luminosity Function of Field Galaxies
Short Name:
J/MNRAS/312/557
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a measurement of the K-band luminosity function (LF) of field galaxies obtained from near-infrared imaging of a sample of 345 galaxies selected from the Stromlo-APM Redshift Survey. The LF is reasonably well fitted over the 10-mag range -26 < M(K-band) < -16 by a Schechter function with the parameters {alpha}=-1.16+/-0.19, M*=-23.58+/-0.42 and {phi*}=0.012+/-0.008 Mpc-3, assuming a Hubble constant of 100 km.s-1.Mpc-1. We have also estimated the LF for two subsets of galaxies subdivided by the equivalent width of the H{alpha} emission line at EW(H{alpha})=1nm. There is no significant difference in LF shape between the two samples, although there is a hint (~1{sigma} significance) that emission-line galaxies (ELGs) have M* roughly 1 mag fainter than non-ELGs. Contrary to the optical LF, there is no difference in the faint end slope {alpha} between the two samples.
3276. K-band spectral catalog of Quintuplet cluster
ID:
ivo://CDS.VizieR/J/A+A/494/1137
Title:
K-band spectral catalog of Quintuplet cluster
Short Name:
J/A+A/494/1137
Date:
21 Oct 2021
Publisher:
CDS
Description:
Three very massive clusters are known to reside in the Galactic center region, the Arches cluster, the Quintuplet cluster, and the central parsec cluster, each of them rich in young hot stars. With new infrared instruments, this region is no longer obscured for the observer. For understanding these very massive clusters, it is essential to know their stellar inventory. We provide comprehensive spectroscopic data for the stellar population of the Quintuplet cluster that will form the basis of subsequent spectral analyses. Spectroscopic observations of the Quintuplet cluster were obtained with the Integral Field Spectrograph SINFONI-SPIFFI at the ESO-VLT, with the ESO VLT UT4 (Yepun) telescope between May and July 2006. The inner part of the Quintuplet cluster covered by 22 slightly overlapping fields, each of them of 8"x8" in size. The spectral range comprises the near-IR K-band from 1.94 to 2.45um. The 3D data cubes of the individual fields were flux-calibrated and combined to one contiguous cube, from which the spectra of all detectable point sources were extracted.
3277. K-band spectrum of the very massive star W49nr1
ID:
ivo://CDS.VizieR/J/A+A/568/L13
Title:
K-band spectrum of the very massive star W49nr1
Short Name:
J/A+A/568/L13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Very massive stars (M>100M_{sun}_) are very rare objects, but have a strong influence on their environment. The formation of this kind of objects is of prime importance in star formation, but observationally still poorly constrained. We report on the identification of a very massive star in the central cluster of the star-forming region W49. We investigate near-infrared K-band spectroscopic observations of W49 from VLT/ISAAC together with JHK images obtained with NTT/SOFI and LBT/LUCI. We derive a spectral type of W49nr1, the brightest star in the dense core of the central cluster of W49.
3278. K-band survey in high galactic latitude
ID:
ivo://CDS.VizieR/II/211
Title:
K-band survey in high galactic latitude
Short Name:
II/211
Date:
21 Oct 2021
Publisher:
CDS
Description:
The survey is a high galactic latitude, large area (552 square arcmin) blank-field sample to a 5{sigma} limit of K=17.3mag. Star-galaxy discrimination is performed. The infrared observations were made over the period 1987-1988, using the infrared camera IRCAM at the 3.8m UKIRTelescope at Mauna Kea, Hawai. The pixel size is 1.2arcsec. The redshift survey (spectro.dat) concerns 124 galaxies of the survey, and was carried out on the Anglo-Australian telescope and the William Herschel telescope at La Palma over the period 1990-1992, with a multi-fibre spectrograph for the brighter objects (R<19), long and multi-slit spectrographs for fainter objects.
3279. K2-141 b radial velocity and light curve
ID:
ivo://CDS.VizieR/J/A+A/612/A95
Title:
K2-141 b radial velocity and light curve
Short Name:
J/A+A/612/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the discovery of K2-141 b (EPIC 246393474 b), an ultra-short-period super-Earth on a 6.7-hour orbit transiting an active K7 V star based on data from K2 campaign 12. We confirmed the planet's existence and measured its mass with a series of follow-up observations: seeing-limited MuSCAT imaging, NESSI high-resolution speckle observations, and FIES and HARPS high-precision radial-velocity monitoring. K2-141 b has a mass of 5.31+/-0.46M_{Earth}_ and radius of 1.54+0.10-0.09R_{Earth}_, yielding a mean density of 8.00^+1.83^_-1.45_g/cm^3^ and suggesting a rocky-iron composition. Models indicate that iron cannot exceed ~70% of the total mass. With an orbital period of only 6.7 hours, K2-141 b is the shortest-period planet known to date with a precisely determined mass.
3280. K corrections as a function of stellar param.
ID:
ivo://CDS.VizieR/J/A+A/658/A148
Title:
K corrections as a function of stellar param.
Short Name:
J/A+A/658/A148
Date:
22 Feb 2022
Publisher:
CDS
Description:
Relativistic corrections are estimated for classical Cepheids and the Tip of the Red Giant Branch (TRGB stars), to enable future unbiased 1% measurements of Hubble's constant, H0. We considered four effects: K corrections, time-dilation, the apparent change of host dust extinction due to non-comoving reference frames, and the change of observed color due to redshift. Extinction-dependent K corrections were computed using stellar atmosphere models applicable to giant stars for 0.005<z<0.030 in HST, JWST, and 2MASS filters. The optical-NIR Wesenheit function advantageously combines filters with oppositely signed K-corrections and avoids complications due to host extinction. For TRGB stars, the JWST/NIRCAM F277W filter combines insensitivity to reddening with K corrections <1% at Coma cluster distances. Missing corrections for host extinction due to circumgalactic or circumstellar material are discussed as potential systematics for TRGB distances although their impacts are insufficient to explain differences between H0 based on Cepheid or TRGB supernova calibrations. All stellar standard candles require relativistic corrections to achieve an unbiased 1% H0 measurement in the future. The combined relativistic correction involving K, redshift-Leavitt bias, and the redshift-dependence of the Wesenheit function yield an increase of the Cepheid-based H0 by 0.45+/-0.05km/s/Mpc to 73.65+/-1.30km/s/Mpc and raises the tension with the Planck value from 4.2 to 4.4 sigma. For TRGB stars, we estimate a ~0.5% increase of H0 reported by Freedman et al. (to 70.2+/-1.7km/s/Mpc) and a small decrease by -0.15% for H0 reported by Anand et al. (to 71.4+/-1.8km/s/Mpc). The opposite sign of these corrections is due to different reddening systematics and reduces the difference between the studies by ~0.46km/s/Mpc. The optical-NIR Wesenheit function is particularly attractive for accurate distance measurements because it advantageously combines measurements in filters where K-corrections have opposite signs. The JWST/NIRCAM F277W filter is of particular interest for TRGB stars thanks to its insensitivity to (weak) host reddening and K-corrections below the level of 1% at Coma cluster distances.