- ID:
- ivo://CDS.VizieR/J/ApJ/765/94
- Title:
- Calibration of the mid-IR Tully-Fisher relation
- Short Name:
- J/ApJ/765/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Distance measures on a coherent scale around the sky are required to address the outstanding cosmological problems of the Hubble constant and of departures from the mean cosmic flow. The correlation between galaxy luminosities and rotation rates can be used to determine the distances to many thousands of galaxies in a wide range of environments potentially out to 200Mpc. Mid-infrared (3.6{mu}m) photometry with the Spitzer Space Telescope is particularly valuable as a source of luminosities because it provides products of uniform quality across the sky. From a perch above the atmosphere, essentially the total magnitude of targets can be registered in exposures of a few minutes. Extinction is minimal and the flux is dominated by the light from old stars, which is expected to correlate with the mass of the targets. In spite of the superior photometry, the correlation between mid-infrared luminosities and rotation rates extracted from neutral hydrogen profiles is slightly degraded from the correlation found with I-band luminosities. A color correction recovers a correlation that provides comparable accuracy to that available at the I band (~20% 1{sigma} in an individual distance) while retaining the advantages identified above. Without color correction, the relation between linewidth and [3.6] magnitudes is M^b,i,k,a^_[3.6]_=-20.34-9.74(logW^i^_mx_-2.5). This description is found with a sample of 213 galaxies in 13 clusters that define the slope and 26 galaxies with Cepheid or tip of the red giant branch distances that define the zero point. A color-corrected parameter M_c[3.6]_ is constructed that has reduced scatter: M_c[3.6]_=-20.34-9.13(logW_mx_^i^-2.5). Consideration of the seven calibration clusters beyond 50Mpc, outside the domain of obvious peculiar velocities, provides a preliminary Hubble constant estimate of H_0_=74+/-4km/s.M/pc.
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- ID:
- ivo://CDS.VizieR/J/ApJ/533/744
- Title:
- Calibration of the Tully-Fischer relation
- Short Name:
- J/ApJ/533/744
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The correlation between the luminosities and rotation velocities of galaxies can be used to estimate distances to late-type galaxies. It is an appropriate moment to reevaluate this method given the great deal of new information available. The major improvements described here include: (1) the template relations can now be defined by large, complete samples, (3) the samples are drawn from a wide range of environments, (3) the relations are defined by photometric information at the B, R, I, and K' bands, (4) the multiband information clarifies problems associated with internal reddening, (5) the template zero points are defined by 24 galaxies with accurately known distances, and (6) the relations are applied to 12 clusters scattered across the sky and out to velocities of 8000km/s.
- ID:
- ivo://CDS.VizieR/J/other/PASA/37.22
- Title:
- Calibration sample UBV and GALEX photometry
- Short Name:
- J/other/PASA/37.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive transformation equations between GALEX and UBV colours by using the reliable data of 556 stars. We present two sets of equations: as a function of (only) luminosity class and as a function of both luminosity class and metallicity. The metallicities are provided from the literature, while the luminosity classes are determined by using the PARSEC mass tracks in this study. Small colour residuals and high squared correlation coefficients promise accurate derived colours. The application of the transformation equations to 70 stars with reliable data shows that the metallicity plays an important role in estimation of more accurate colours.
- ID:
- ivo://CDS.VizieR/J/AJ/162/191
- Title:
- 2011-2021 calibrator observations of SCUBA-2
- Short Name:
- J/AJ/162/191
- Date:
- 14 Mar 2022 06:52:03
- Publisher:
- CDS
- Description:
- The Submillimetre Common User Bolometer Array 2 (SCUBA-2) is the James Clerk Maxwell Telescope's continuum imager, operating simultaneously at 450 and 850{mu}m. SCUBA-2 was commissioned in 2009-2011, and since that time, regular observations of point-like standard sources have been performed whenever the instrument is in use. Expanding the calibrator observation sample by an order of magnitude compared to previous work, in this paper we derive updated opacity relations at each wavelength for a new atmospheric extinction correction, analyze the Flux Conversion Factors used to convert instrumental units to physical flux units as a function of date and observation time, present information on the beam profiles for each wavelength, and update secondary calibrator source fluxes. Between 07:00 and 17:00 UTC, the portion of the night that is most stable to temperature gradients that cause dish deformation, the total flux uncertainty and the peak flux uncertainty measured at 450{mu}m are found to be 14% and 17%, respectively. Measured at 850{mu}m, the total flux and peak flux uncertainties are 6% and 7%, respectively. The analysis presented in this work is applicable to all SCUBA-2 projects observed since 2011.
- ID:
- ivo://CDS.VizieR/J/MNRAS/414/108
- Title:
- Calibrator of exoplanet-host stars
- Short Name:
- J/MNRAS/414/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Phase-referenced interferometric astrometry offers the possibility to look for exoplanets around bright stars. Instruments like PRIMA (Phase-Referenced Imaging and Micro-arcsecond Astrometry) will measure the astrometric wobble of a candidate star due to an exoplanet relative to a close-by 'calibrator' star, located within the instrument's observing field (1-arcmin in the PRIMA case). Stars with already known exoplanets will constitute the first targets for this technique, as it will provide a way to further specify the characteristics of the known exoplanets, such as the inclinations. The main requirement is to have a calibrator in the vicinity of the star. We provide here a list of calibrators for all stars with known exoplanets obtained using data mining and Virtual Observatory techniques. This list is available online and revised regularly. The calibrators are found from catalogues available at Centre de Donnees astronomiques de Strasbourg (CDS) using the SearchCal software developed at Jean-Marie Mariotti Center (JMMC). In our test case, the calibrators are found within 1 arcmin angular distance for approximately 50 per cent of the stars tested, and often closer. They are all faint objects from the Two Micron All Sky Survey (2MASS) with K magnitudes between 13 and 15. A list of the most promising targets is also given.
- ID:
- ivo://CDS.VizieR/J/AJ/153/16
- Title:
- Calibrator stars catalog for interferometers
- Short Name:
- J/AJ/153/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Benchmark stars with known angular diameters are key to calibrating interferometric observations. With the advent of optical interferometry, there is a need for suitably bright, well-vetted calibrator stars over a large portion of the sky. We present a catalog of uniformly computed angular diameters for 1510 stars in the northern hemisphere, brighter than V=6 and with declinations -15{deg}<delta<82{deg}. The median angular stellar diameter is 0.529 mas. The list has been carefully cleansed of all known binary and multiple stellar systems. We derive the angular diameters for each of the stars by fitting spectral templates to the observed spectral energy distributions (SEDs) from literature fluxes. We compare these derived angular diameters against those measured by optical interferometry for 75 of the stars, as well as to 176 diameter estimates from previous calibrator catalogs, finding in general excellent agreement. The final catalog includes our goodness-of-fit metrics as well as an online atlas of our SED fits. The catalog presented here permits selection of the best calibrator stars for current and future visible-light interferometric observations.
- ID:
- ivo://CDS.VizieR/J/A+A/433/1155
- Title:
- Calibrator stars for 200m baseline interferometry
- Short Name:
- J/A+A/433/1155
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of reference stars suitable for calibrating infrared interferometric observations. In the K band, visibilities can be calibrated with a precision of 1% on baselines up to 200 meters for the whole sky, and up to 300 meters for some part of the sky. This work, extending to longer baselines a previous catalog compiled by Borde et al. (2002, Cat. <J/A+A/393/183>), is particularly well adapted to hectometric-class interferometers. We use the absolute spectro-photometric calibration method introduced by Cohen et al. (1999AJ....117.1864C) to derive the angular diameters of our new set of stars.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A47
- Title:
- CALIFA color/metallicity gradients connections
- Short Name:
- J/A+A/585/A47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study, for the first time in a statistically significant and well-defined sample, the relation between the outer-disk ionized-gas metallicity gradients and the presence of breaks in the surface brightness profiles of disk galaxies. Sloan Digital Sky Survey (SDSS) g'- and r'-band surface brightness, (g'-r') color, and ionized-gas oxygen abundance profiles for 324 galaxies within the Calar Alto Legacy Integral Field Area (CALIFA) survey are used for this purpose. We perform a detailed light-profile classification, finding that 84% of our disks show down- or up-bending profiles (Type II and Type III, respectively), while the remaining 16% are well fitted by one single exponential (Type I). The analysis of the color gradients at both sides of this break shows a U-shaped profile for most Type II galaxies with an average minimum (g'-r') color of ~0.5mag and an ionized-gas metallicity flattening associated with it only in the case of low-mass galaxies. Comparatively, more massive systems show a rather uniform negative metallicity gradient. The correlation between metallicity flattening and stellar mass for these systems results in p-values as low as 0.01. Independent of the mechanism having shaped the outer light profiles of these galaxies, stellar migration or a previous episode of star formation in a shrinking star-forming disk, it is clear that the imprint in their ionized-gas metallicity was different for low- and high-mass Type II galaxies. In the case of Type III disks, a positive correlation between the change in color and abundance gradient is found (the null hypothesis is ruled out with a p-value of 0.02), with the outer disks of Type III galaxies with masses <=10^10^M_{sun}_ showing a weak color reddening or even a bluing. This is interpreted as primarily due to a mass downsizing effect on the population of Type III galaxies that recently experienced an enhanced inside-out growth.
2379. CALIFA DR2
- ID:
- ivo://CDS.VizieR/J/A+A/576/A135
- Title:
- CALIFA DR2
- Short Name:
- J/A+A/576/A135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5m telescope at the Calar Alto observatory. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the wavelength range 3745-7500{AA} with a spectral resolution of 6.0{AA} (FWHM); and (ii) a medium-resolution V1200 setup covering the wavelength range 3650-4840{AA} with a spectral resolution of 2.3{AA} (FWHM). The sample covers a redshift range between 0.005 and 0.03, with a wide range of properties in the color-magnitude diagram, stellar mass, ionization conditions, and morphological types. All the cubes in the data release were reduced with the latest pipeline, which includes improved spectrophotometric calibration, spatial registration, and spatial resolution. The spectrophotometric calibration is better than 6% and the median spatial resolution is 2.4". In total, the second data release contains over 1.5 million spectra.
- ID:
- ivo://CDS.VizieR/J/MNRAS/491/3562
- Title:
- CALIFA ETGs spatially resolved stellar pop.
- Short Name:
- J/MNRAS/491/3562
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform spatially resolved stellar population analysis for a sample of 69 early-type galaxies (ETGs) from the CALIFA integral field spectroscopic survey, including 48 ellipticals and 21 S0's. We generate and quantitatively characterize profiles of light-weighted mean stellar age and metallicity within <~2Re, as a function of radius and stellar-mass surface density {mu}*. We study in detail the dependence of profiles on galaxies' global properties, including velocity dispersion {sigma}_e_, stellar mass, morphology. ETGs are universally characterized by strong, negative metallicity gradients (~-0.3dex per Re) within 1Re, which flatten out moving towards larger radii. A quasi-universal local {mu}*-metallicity relation emerges, which displays a residual systematic dependence on {sigma}_e_, whereby higher {sigma}_e_ implies higher metallicity at fixed {mu}*. Age profiles are typically U-shaped, with minimum around 0.4Re, asymptotic increase to maximum ages beyond ~1.5Re, and an increase towards the centre. The depth of the minimum and the central increase anticorrelate with {sigma}_e_. A possible qualitative interpretation of these observations is a two-phase scenario. In the first phase, dissipative collapse occurs in the inner 1Re, establishing a negative metallicity gradient. The competition between the outside-in quenching due to feedback-driven winds and some form of inside-out quenching, possibly caused by central AGN feedback or dynamical heating, determines the U-shaped age profiles. In the second phase, the accretion of ex-situ stars from quenched and low-metallicity satellites shapes the flatter stellar population profiles in the outer regions.
