- ID:
- ivo://CDS.VizieR/J/A+A/633/A159
- Title:
- Bright Lyman-alpha emitters in MUSE/COSMOS field
- Short Name:
- J/A+A/633/A159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We search for the presence of bright Ly-alpha emitters among Spitzer SMUVS galaxies at z>2.9 making use of homogeneous MUSE spectroscopic data. Although these data only cover a small region of COSMOS, MUSE has the unique advantage of providing spectral information over the entire field, without the need of target pre-selection. This results in an unbiased detection of all the brightest Ly-alpha emitters among the SMUVS sources, which by design are stellar-mass selected galaxies. Within the studied area, ~14% of the SMUVS galaxies at z>2.9 have Ly-alpha fluxes F_{lambda}_>~7x10^-18^erg/s/cm^2^. These Ly-alpha emitters are characterized by three types of emission, 47% show a single line profile, 19% present a double peak or a blue bump and 31% show a red tail. One object (3%) shows both a blue bump and a red tail. We also investigate the spectral energy distribution (SED) properties of the SMUVS galaxies which are MUSE detected and which are not. After stellar-mass matching both populations, we find that the MUSE detected galaxies have generally lower extinction than SMUVS-only objects, while there is no clear intrinsic difference in the mass and age distributions of the two samples. For the MUSE-detected SMUVS galaxies, we compare the instantaneous SFR lower limit obtained from the Ly-alpha line with its past average derived from SED fitting, and find evidence for rejuvenation in some of our oldest objects. In addition, we study the spectra of those Ly-alpha emitters which are not detected in SMUVS in the same field. We find that the emission line profile shown are 67% a single line, 3% a blue bump and 20% a red tail profile. The difference in profile distribution could be ascribed to the fainter Ly-alpha luminosities of the MUSE sources not detected in SMUVS and an intrinsically different mass distribution. Finally, we search for the presence of galaxy associations using the spectral redshifts. MUSE's integral coverage reveals that these associations are 20 times more likely than what is derived from all the other existing spectral data in COSMOS, which is biased by target pre-selection.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/652/1585
- Title:
- Bright metal-poor stars from HES survey
- Short Name:
- J/ApJ/652/1585
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 1777 bright (9<B<14) metal-poor candidates selected from the Hamburg/ESO Survey (HES). Despite saturation effects present in the red portion of the HES objective-prism spectra, the data were recoverable and quantitative selection criteria could be applied to select the sample. Analyses of medium-resolution (~2{AA}) follow-up spectroscopy of the entire sample, obtained with several 24m class telescopes, yielded 145 new metal-poor stars with metallicity [Fe/H]<-2.0, of which 79 have [Fe/H]<-2.5 and 17 have [Fe/H]<-3.0. We also obtained C/Fe estimates for all of these stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/81
- Title:
- Bright metal-poor stars from HES Survey. II.
- Short Name:
- J/ApJ/835/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We obtain estimates of stellar atmospheric parameters for a previously published sample of 1777 relatively bright (9<B<14) metal-poor candidates from the Hamburg/ESO Survey. The original Frebel+ (2006, J/ApJ/652/1585; Paper I) analysis of these stars was able to derive estimates of [Fe/H] and [C/Fe] only for a subset of the sample, due to limitations in the methodology then available. A new spectroscopic analysis pipeline has been used to obtain estimates of T_eff_, logg, [Fe/H], and [C/Fe] for almost the entire data set. This sample is very local-about 90% of the stars are located within 0.5kpc of the Sun. We consider the chemodynamical properties of these stars in concert with a similarly local sample of stars from a recent analysis of the Bidelman and MacConnell "weak metal" candidates by Beers+ (2014, J/ApJ/794/58). We use this combined sample to identify possible members of the halo stream of stars suggested by Helmi+ (1999Natur.402...53H) and Chiba & Beers (2000AJ....119.2843C), as well as stars that may be associated with stripped debris from the putative parent dwarf of the globular cluster Omega Centauri, suggested to exist by previous authors. We identify a clear increase in the cumulative frequency of carbon-enhanced metal-poor (CEMP) stars with declining metallicity, as well as an increase in the fraction of CEMP stars with distance from the Galactic plane, consistent with previous results. We also identify a relatively large number of CEMP stars with kinematics consistent with the metal-weak thick-disk population, with possible implications for its origin.
- ID:
- ivo://CDS.VizieR/J/A+A/621/A60
- Title:
- Bright nearby elliptical gal. Xshooter spectra
- Short Name:
- J/A+A/621/A60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new generation of spectral synthesis models has been developed in the recent years, but there is no matching -- in terms of quality and resolution -- set of template galaxy spectra for testing and refining the new models. Our main goal is to find and calibrate new near-infrared spectral indices along the Hubble sequence of galaxies which will be used to obtain additional constraints to the population analysis based on medium resolution integrated spectra of galaxies. Spectra of previously studied and well understood galaxies with relatively simple stellar populations (e.g., ellipticals or bulge dominated galaxies) are needed to provide a baseline data set for spectral synthesis models. X-Shooter spectra spanning the optical and infrared wavelength (350-2400nm) of bright nearby elliptical galaxies with resolving power R~4000-5400 were obtained. Heliocentric systemic velocity, velocity dispersion and Mg, Fe and H{beta} line-strength indices are presented. We present a library of very high quality spectra of galaxies covering a large range of age, metallicity and morphological type. Such as a dataset of spectra will be crucial to address important questions of the modern investigation concerning galaxy formation and evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/435/437
- Title:
- Brightness and diameters for extragalactic SNRs
- Short Name:
- J/A+A/435/437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper examines relations between the radio surface brightness Sigma and the diameter D (also known as Sigma-D relations) for a sample of extragalactic supernova remnants (SNRs) as constructed from a combination of published data and data from our own surveys. Our sample of extragalactic SNRs is the largest ever devised for the purpose of analyzing Sigma-D relations.
- ID:
- ivo://CDS.VizieR/J/AJ/156/207
- Title:
- Brightness of active Ionian volcanoes
- Short Name:
- J/AJ/156/207
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Tidal heating is the major source of heat in the outer solar system. Because of its strong tidal interaction with Jupiter and the other Galilean satellites, Io is incredibly volcanically active. We use the directly measured volcanic activity level of Io's volcanoes as a proxy for surface heat flow and compare it to tidal heating model predictions. Volcanic activity is a better proxy for heat flow than simply the locations of volcanic constructs. We determine the volcanic activity level using three data sets: the Galileo Photopolarimeter Radiometer (PPR), Galileo Near-Infrared Mapping Spectrometer (NIMS), and New Horizons LEISA. We also present a systematic reanalysis of the Galileo NIMS observations to determine the 3.5 {mu}m brightness of 51 active volcanoes. We find that potential differences in volcanic style between high and low latitudes make high-latitude observations unreliable for distinguishing between tidal heating models. Observations of Io's polar areas, such as those by Juno, are necessary to unambiguously understand Io's heat flow. However, all three of the data sets examined show a relative dearth of volcanic brightness near 180 W (anti-Jovian point) and the equator, and the only data set with good observations of the sub-Jovian point (LEISA) also shows a lack of volcanic brightness in that region. These observations are more consistent with the mantle-heating model than the asthenospheric-heating model. Furthermore, all three of the data sets are consistent with fourfold symmetry in longitude and peak heat flow at mid-latitudes, which best matches with the combined heating case of Tackley et al. (2001Icar..149...79T).
1887. Brightness of SN 2006X
- ID:
- ivo://CDS.VizieR/J/AZh/84/1110
- Title:
- Brightness of SN 2006X
- Short Name:
- J/AZh/84/1110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of observations over 2005-2006 years at the robotic telescope MASTER are presented. There are the first in the world observation of optical emission of GRB 050824 and GRB 060926 gamma-ray bursts. Our data combined with more later one gives the low of brightness drop t^-0.55+/-0.05^ for GRB 050824. We discovered optical flare for GRB 060926 around 500-700s. The power low spectral index (F_E_~E^-beta^) is equal beta=1.0+/-0.2. In the course of sky survey we have images of more than 90% possible sky. The virtual data-base and pipe-line was made. The limit to the orphan optical bursts rate is presented. We discovered 3 supernovae stars, they are the following: SN 2005bv (Ia-type) is the first one, opened from Russian territory, SN 2005ee is one of the most powerful among II-type supernovae, SN 2006ak (Ia-type). New method of the OT search after IPN-triangulation gamma-observation is proposed and tested.
- ID:
- ivo://CDS.VizieR/J/A+A/549/A133
- Title:
- Bright northern radio sources with VLA/JVLA
- Short Name:
- J/A+A/549/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report multiple epoch VLA/JVLA observations of 89 northern hemisphere sources, most with 37GHz flux density >1Jy, observed at 4.8, 8.5, 33.5, and 43.3GHz. The high frequency selection leads to a predominantly flat spectrum sample, with 85% of our sources being in the Planck Early Release Compact Source Catalog (ERCSC, Cat. VIII/88). These observations allow us to: 1) validate Planck's 30 and 44GHz flux density scale; 2) extend the radio spectral energy distributions of Planck sources to lower frequencies allowing for the full 5-857GHz regime to be studied; and 3) characterize the variability of these sources. At 30GHz and 44GHz, the JVLA and Planck flux densities agree to within ~3%. On timescales of less than two months the median variability of our sources is 2%. On timescales of about a year the median variability increases to 14%. Using the WMAP 7-year data, the 30GHz median variability on a 1-6 years timescale is 16%.
- ID:
- ivo://CDS.VizieR/J/ApJ/887/268
- Title:
- Bright QSOs in Southern Hemisphere (QUBRICS)
- Short Name:
- J/ApJ/887/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of absorptions along the lines of sight to bright high-z QSOs is an invaluable cosmological tool that provides a wealth of information on the inter-/circum-galactic medium, dark matter, primordial elements, reionization, fundamental constants, and general relativity. Unfortunately, the number of bright (i<~18) QSOs at z>~2 in the southern hemisphere is much lower than that in the north, due to the lack of wide multiwavelength surveys at decl. {delta}<0{deg}, hampering the effectiveness of observations from southern observatories. In this work we present a new method based on Canonical Correlation Analysis to identify such objects, taking advantage of a number of available databases: Skymapper, Gaia DR2, WISE, and 2MASS. Our QSO candidate sample lists 1476 sources with i<18 over 12400deg^2^ in the southern hemisphere. With a preliminary campaign we observed spectroscopically 69 of them, confirming 54 new bright QSOs at z>2.5, corresponding to a success rate of our method of ~80%. Furthermore, we estimate a completeness of ~90% of our sample at completion of our observation campaign. The new QSOs confirmed by this first and the forthcoming campaigns (QUBRICS survey) will be the targets of subsequent studies using higher resolution spectrographs, like ESPRESSO, UVES, and (in the long term) ELT/HIRES.
- ID:
- ivo://CDS.VizieR/J/MNRAS/204/151
- Title:
- Bright radio sources at 178 MHz (3CRR)
- Short Name:
- J/MNRAS/204/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A revised sample of bright radio sources at 178MHz is defined in order to correct the biases introduced into the 3CR catalog by confusion and partial resolution. The sample is shown to be 96 percent complete to a flux-density limit of 10Jy for sources smaller than 10arcmin. The bias of the 3CR catalog against objects of larger angular size is also reduced. Optical identifications are presented for 96 percent of the sources, 71 percent with galaxies and 25 percent with quasars. The radio-galaxy population is found to show strong space-density evolution for luminosities in excess of approximately 10^26.5^W/Hz/sr at 178MHz (redshifts greater than or approximately equal to 0.2), while the evolutionary properties of galaxies and quasars of the same luminosity and redshift are very similar.
