We present a new calibration of the calcium II triplet equivalent widths versus [Fe/H], constructed upon K giant stars in the Galactic bulge. This calibration will be used to derive iron abundances for the targets of the GIBS survey, and is in general especially well suited for solar and supersolar metallicity giants, which are typical of external massive galaxies. To obtain the calibration, about 150 bulge K giants were observed with the GIRAFFE spectrograph at the VLT with a resolution of R~20000 and at R~6000. In the first case, the spectra allowed us to directly determine the Fe abundances from several unblended Fe lines, deriving what we call here high-resolution [Fe/H] measurements. The low-resolution spectra allowed us to measure equivalent widths of the two strongest lines of the near-infrared calcium II triplet at 8542 and 8662{AA}. By comparing the two measurements, we derived a relation between calcium equivalent widths and [Fe/H] that is linear over the metallicity range probed here, -1<[Fe/H]<+0.7. By adding a small second-order correction based on literature globular cluster data, we derived the unique calibration equation [Fe/H]_CaT_=-3.150+0.432W'+0.006W'^2^, with an rms dispersion of 0.197dex, valid across the whole metallicity range -2.3<[Fe/H]<+0.7.
Although the colour distribution of globular clusters in massive galaxies is well known to be bimodal, the spectroscopic metallicity distribution has been measured in only a few galaxies. After redefining the calcium triplet index-metallicity relation, we use our relation to derive the metallicity of 903 globular clusters in 11 early-type galaxies. This is the largest sample of spectroscopic globular cluster metallicities yet assembled. We compare these metallicities with those derived from Lick indices finding good agreement. In six of the eight galaxies with sufficient numbers of high-quality spectra we find bimodality in the spectroscopic metallicity distribution. Our results imply that most massive early-type galaxies have bimodal metallicity as well as colour distributions. This bimodality suggests that most massive early-type galaxies experienced two periods of star formation.
The CatWISE2020 catalog contains positions and brightnesses for 1,890,715,640 sources selected from combined WISE and NEOWISE all-sky survey data collected from 2010 to 2018 at 3.4 and 4.6 microns (W1 and W2). CatWISE adapts AllWISE software to measure the sources in co-added images created from six month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 12 epochs over the 8 year span of the data.
The CatWISE Preliminary catalog contains positions and brightnesses for 900,849,014 sources selected from combined WISE and NEOWISE all-sky survey data collected from 2010 to 2016 at 3.4 and 4.6 microns (W1 and W2). CatWISE adapts AllWISE software to measure the sources in co-added images created from six month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 8 epochs over the 6 year span of the data.
The CatWISE Preliminary catalog contains positions and brightnesses for 900,849,014 sources selected from combined WISE and NEOWISE all-sky survey data collected from 2010 to 2016 at 3.4 and 4.6 microns (W1 and W2). CatWISE adapts AllWISE software to measure the sources in co-added images created from six month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 8 epochs over the 6 year span of the data.
The CatWISE2020 Reject Table contains positions and brightnesses for 341,799,385 sources selected from combined WISE and NEOWISE all-sky survey data collected from 2010 to 2018 at 3.4 and 4.6 microns (W1 and W2). CatWISE2020 adapts AllWISE software to measure the sources in co-added images created from six month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 12 epochs over the 8 year span of the data.
The initial conditions for the gravitational collapse of molecular cloud cores and the subsequent birth of stars are still not well constrained. The characteristic cold temperatures (~10K) in such regions require observations at sub-millimetre and longer wavelengths. The Herschel Space Observatory and complementary ground-based observations presented in this paper have the unprecedented potential to reveal the structure and kinematics of a prototypical core region at the onset of stellar birth. This paper aims to determine the density, temperature, and velocity structure of the star-forming Bok globule CB 17. This isolated region is known to host (at least) two sources at different evolutionary stages: a dense core, SMM1, and a Class I protostar, IRS. We modeled the cold dust emission maps from 100{mu}m to 1.2mm with both a modified blackbody technique to determine the optical depth-weighted line-of-sight temperature and column density and a ray-tracing technique to determine the core temperature and volume density structure. Furthermore, we analysed the kinematics of CB17 using the high-density gas tracer N_2_H^+
We present the results of the flux density measurements at 4.85GHz and 10.45GHz of a sample of 5998 NVSS radio sources with the Effelsberg 100m telescope. The initial motivation was the need to identify the NVSS radio sources that could potentially contribute significant contaminating flux in the frequency range at which the Cosmic Background Imager experiment operated.
We observed the cluster Cl 1409+524 (z=0.46) with an imaging Fabry-Perot interferometer. A sequence of Fabry-Perot images (FWHM=1.0-1.3nm) was used to search for redshifted [OII]{lambda}372.7nm- and [OIII]{lambda}500.7nm line emission. We studied 144 galaxies up to a limiting continuum R-band magnitude of 22.5mag within 1 Mpc around the cluster center. Previously known emission-line galaxies in the cluster were confirmed and 17 new members with emission lines were found. Their star formation rate of 1-2M_{sun}_/yr is typical for normal spirals. We have imaged the cluster with broad band B, R and seven intermediate band filters (FWHM=10.0-20.0nm) in order to derive low-resolution spectral energy distributions of cluster galaxies. These were fitted by template spectra to estimate Hubble class and redshifts. Based on this decomposition, we derived a percentage of emission-line galaxies of 40+/-11%.
