- ID:
- ivo://CDS.VizieR/J/A+A/440/61
- Title:
- FORS spectroscopy of HDFS galaxies
- Short Name:
- J/A+A/440/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present low resolution multi-object spectroscopy of an I-band magnitude limited (I_AB_~23-23.5) sample of galaxies located in an area centered on the Hubble Deep Field-South (HDFS). The observations were obtained using the Focal Reducer/low dispersion Spectrograph (FORS) on the ESO Very Large Telescope. Thirty-two primary spectroscopic targets in the HST-WFPC2 HDFS were supplemented with galaxies detected in the Infrared Space Observatory's survey of the HDFS and the ESO Imaging Deep Survey to comprise a sample of 100 galaxies for spectroscopic observations. Based on detections of several emission lines, such as [OII]3727, H{beta} and [OIII]5007, or of other spectroscopic features, we measured accurate redshifts for 50 objects in the central HDFS and flanking fields. The redshift range of the current sample of galaxies is 0.6-1.2, with a median redshift of 1.13 (at I~23.5 not corrected for completeness). The sample is dominated by starburst galaxies with only a small fraction of ellipticals (~10%). For the emission line objects, the extinction corrected [OII]3727 line strengths yield estimates of star formation rates in the range 0.5-30M_{sun}_/yr. We used the present data to derive the [OII]3727 luminosity function up to redshift of 1.2. When combined with [OII]3727 luminosity densities for the local and high redshift Universe, our results confirm the steep rise in the star formation rate (SFR) to z~1.3.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/596/A47
- Title:
- FORS2 transmission spectroscopy of WASP-17b
- Short Name:
- J/A+A/596/A47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present FORS2 (attached to ESO's Very Large Telescope) observations of the exoplanet WASP-17b during its primary transit, for the purpose of differential spectrophotometry analysis. We use the instrument in its Mask eXchange Unit (MXU) mode to simultaneously obtain low resolution spectra of the planet hosting star, as well as several reference stars in the field of view. The integration of these spectra within broadband and smaller 100{AA} bins provides us with 'white' and spectrophotometric light curves, from 5700 to 8000{AA}. Through modelling the white light curve, we obtain refined bulk and transit parameters of the planet, as well as wavelength-dependent variations of the planetary radius from smaller spectral bins through which the transmission spectrum is obtained. The inference of transit parameters, as well as the noise statistics, is performed using a Gaussian Process model. We achieve a typical precision in the transit depth of a few hundred parts per million from various transit light curves. From the transmission spectra we rule out a flat spectrum at >3{sigma} and detect marginal presence of the pressure-broadened sodium wings. Furthermore, we detect the wing of the potassium absorption line in the upper atmosphere of the planet with 3-{sigma} confidence, both facts pointing to a relatively shallow temperature gradient in the atmosphere. These conclusions are mostly consistent with previous studies of this exo-atmosphere, although previous potassium measurements have been inconclusive.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/34
- Title:
- Fourier transform emission spectroscopy of ^13^C^14^N
- Short Name:
- J/ApJS/194/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Emission spectra of the B^2^{Sigma}^+^-X^2^{Sigma}^+^ transition of ^13^C^14^N have been observed at high resolution using the Fourier transform spectrometer associated with the McMath-Pierce Solar Telescope of the National Solar Observatory. The spectra have been measured in the 21000-30000cm^-1^ region and a total of 52 vibrational bands involving vibrational levels up to {nu}=15 of the ground and excited states have been rotationally analyzed to provide a much improved set of spectroscopic constants. An experimental line list and calculated term values are provided. The results of the present analysis should prove useful in the identification of additional ^13^C^14^N lines in comets and cool stars, and will help in the determination of the ^12^C/^13^C abundance ratio.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A23
- Title:
- Frequency analysis of HD 49434
- Short Name:
- J/A+A/525/A23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 49434 is a bright (V=5.75mag) and multiperiodic gamma Dor-type pulsator that has been selected for the asteroseismic core programme of the CoRoT satellite. An extensive and detailed study has been carried out to investigate the pulsational content of this object on the basis of the 136.9d (331291 useful datapoints) time series collected by the CoRoT satellite during the long-run LRa01 (October 2007-March 2008).
- ID:
- ivo://CDS.VizieR/J/A+A/635/A183
- Title:
- Fried Egg Nebula AMBER and GRAVITY observations
- Short Name:
- J/A+A/635/A183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The objective of this work is to study in detail the nature (i.e., geometry, rates) of the mass-loss episodes associated with the yellow hypergiant IRAS 17163-3907. We analysed a large set of optical/near-infrared data, in spectroscopic, photometric, spectropolarimetric, and interferometric modes. We use the optical observations to determine its spectral type and we present the first model independent reconstructed images of IRAS 17163-3907 at 2 micron tracing milli-arcsecond scales. Lastly, we apply a 2D radiative transfer model to fit the dereddened photometry and the radial profiles of published diffraction limited VISIR images at 8.59um, 11.85um and 12.81um simultaneously, adopting a revised distance determination using the new Gaia measurements (DR2).
- ID:
- ivo://CDS.VizieR/J/ApJS/223/12
- Title:
- FTS high resolution of CoIII
- Short Name:
- J/ApJS/223/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectrum of CoIII has been recorded in the region 1562-2564{AA} (64000cm^-1^-39000cm^-1^) by Fourier transform (FT) spectroscopy, and in the region 1317-2500{AA} (164000cm^-1^-40000cm^-1^) using a 10.7m grating spectrograph with phosphor image plate detectors. The spectrum was excited in a cobalt-neon Penning discharge lamp. We classified 514 CoIII lines measured using FT spectroscopy, the strongest having wavenumber uncertainties approaching 0.004cm^-1^ (approximately 0.2m{AA} at 2000{AA}, or 1 part in 10^7^), and 240 lines measured with grating spectroscopy with uncertainties between 5 and 10m{AA}. The wavelength calibration of 790 lines of Raassen & Orti Ortin (1984PhyBC.123..353R) and 87 lines from Shenstone (1960CaJPh..38..677S) has been revised and combined with our measurements to optimize the values of all but one of the 288 previously reported energy levels. Order of magnitude reductions in uncertainty for almost two-thirds of the 3d^6^4s and almost half of the 3d^6^4p revised energy levels are obtained. Ritz wavelengths have been calculated for an additional 100 forbidden lines. Eigenvector percentage compositions for the energy levels and predicted oscillator strengths have been calculated using the Cowan code.
- ID:
- ivo://CDS.VizieR/J/ApJS/227/3
- Title:
- Full spectroscopic data release of the SPT-GMOS
- Short Name:
- J/ApJS/227/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500deg^2^ of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [OII]{lambda}{lambda}3727, 3729 and H-{delta}, and the 4000{AA} break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m*). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ~20% of the full SPT-SZ sample.
- ID:
- ivo://CDS.VizieR/VI/157
- Title:
- Full-spectrum fitting of simple stellar pop.
- Short Name:
- VI/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this second paper of a series on the accuracy and precision of the determination of age and metallicity of simple stellar populations (SSPs) by means of the full spectrum fitting technique, we study the influence of star cluster mass through stochastic fluctuations of the number of stars near the top of the stellar mass function, which dominate the flux in certain wavelength regimes depending on the age.We consider SSP models based on the Padova isochrones, spanning the age range 7.0<=log(age/yr)<=10.1. Simulated spectra of star clusters in the mass range 10^4^<=M/M_{sun}_<10^6^ are compared with SSP model spectra to determine best-fit ages and metallicities using a full-spectrum fitting routine in four wavelength regimes: the blue optical (0.35-0.70um), the red optical (0.6-1.0um), the near-IR (1.0-2.5um), and the mid-IR (2.5-5.0um). We compare the power of each wavelength regime in terms of both the overall precision of age and metallicity determination, and of its dependence on cluster mass. We also study the relevance of spectral resolution in this context by utilizing two different spectral libraries (BaSeL and BT-Settl). We highlight the power of the mid-IR regime in terms of identifying young massive clusters in dusty star forming regions in distant galaxies. The spectra of the simulated star clusters and SSPs are made available online to enable follow-up studies by the community.
- ID:
- ivo://CDS.VizieR/J/ApJ/638/725
- Title:
- Fundamental manifold of spheroids
- Short Name:
- J/ApJ/638/725
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a unifying empirical description of the structural and kinematic properties of all spheroids embedded in dark matter halos. We find that the intracluster stellar spheroidal components of galaxy clusters, which we call cluster spheroids (CSphs) and which are typically 100 times the size of normal elliptical galaxies, lie on a fundamental plane as tight as that defined by elliptical galaxies (rms in effective radius of 0.07) but having a different slope.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/74.62
- Title:
- Fundamental parameters of CP stars
- Short Name:
- J/other/AstBu/74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper presents the results of determination of fundamental parameters (effective temperature, surface gravity, luminosity, mass, radius, rotation velocity, and radial velocity) for 146 stars observed at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences with the Main Stellar Spectrograph during 2009-2011; 124 of the stars are magnetic or potentially magnetic objects. We obtained and analyzed at least 500 pairs of circularly-polarized-emission spectra. Various methods and approaches were used in estimating the fundamental parameters.
