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- ID:
- ivo://CDS.VizieR/J/ApJS/255/22
- Title:
- FRII radio sources dynamical models
- Short Name:
- J/ApJS/255/22
- Date:
- 03 Dec 2021 13:25:10
- Publisher:
- CDS
- Description:
- Dynamical evolution models of 361 extragalactic Fanaroff-Riley type II radio sources selected from the Cambridge 3CRR, 6CE, 5C6, and 5C7 Sky Surveys, as well as the Bologna B2, Green Bank GB, and GB2 Surveys, are presented. Their spectra, compiled mostly from the recent catalogs of radio sources and the available NASA/IPAC and Astrophysical Catalogs Support System databases, along with morphological characteristics of the sources determined from their radio maps, have been modeled using the DYNAGE algorithm and/or its extension (KDA EXT) for the hypothetical case of further evolution after the jet's termination. The best-fit models provide estimates of a number of important physical parameters of the sources, as (i) the jet power, (ii) the density distribution of the external gaseous medium surrounding the radio core and the jet propagating through it, (iii) the initial energy distribution of the relativistic particles accelerated at the shock fronts, and (iv) the age of the observed radio structure. Additionally, estimates of some derivative parameters are provided, e.g., the radio lobes' pressure, their longitudinal expansion velocity, the magnetic field strength, and the total energy deposited in the lobes. The observed spectra and their best-fit models are included. Finally, one of the useful applications of the above models is presented, namely a strong correlation between the ambient medium density and the rest-frame two-point spectral index available directly from the observed spectra.
- ID:
- ivo://CDS.VizieR/J/AJ/147/87
- Title:
- From binaries to multiples. II. Statistical data
- Short Name:
- J/AJ/147/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Statistics of hierarchical multiplicity among solar-type dwarfs are studied using the distance-limited sample of 4847 targets presented in the accompanying Paper I. Known facts about binaries (multiplicity fraction 0.46, lognormal period distribution with median period 100yr and logarithmic dispersion 2.4, and nearly uniform mass-ratio distribution independent of the period) are confirmed with a high statistical significance. The fraction of hierarchies with three or more components is 0.13+/-0.01, and the fractions of targets with n=1,2,3,... components are 54:33:8:4:1. Subsystems in the secondary components are almost as frequent as in the primary components, but in half of such cases both inner pairs are present. The high frequency of those 2+2 hierarchies (4%) suggests that both inner pairs were formed by a common process. The statistics of hierarchies can be reproduced by simulations, assuming that the field is a mixture coming from binary-rich and binary-poor environments. Periods of the outer and inner binaries are selected recursively from the same lognormal distribution, subject to the stability constraint and accounting for the correlation between inner subsystems. The simulator can be used to evaluate the frequency of multiple systems with specified parameters. However, it does not reproduce the observed excess of inner periods shorter than 10days, caused by tidal evolution.
- ID:
- ivo://CDS.VizieR/J/AJ/147/86
- Title:
- From binaries to multiples. I. The FG-67 sample
- Short Name:
- J/AJ/147/86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data on the multiplicity of F- and G-type dwarf stars within 67pc of the Sun are presented. This distance-limited sample based on the Hipparcos catalog contains 4847 primary stars (targets) with 0.5<V-I_C_<0.8 and is >90% complete. There are 2196 known stellar pairs; some of them belong to 361 hierarchical systems from triples to quintuples. Models of companion detection by radial velocity, astrometric acceleration, direct resolution, and common proper motion are developed. They serve to compute completeness for each target, using the information on its coverage collected here. About 80% of companions to the primary stars are detected, but the census of subsystems in the secondary components is only about 30%. Masses of binary components are estimated from their absolute magnitudes or by other methods; the periods of wide pairs are evaluated from their projected separations. A third of binaries with periods shorter than ~100yr are spectroscopic and/or astrometric pairs with yet unknown periods and mass ratios. These data are used in the accompanying Paper II to derive unbiased statistics of hierarchical multiple systems.
- ID:
- ivo://CDS.VizieR/J/A+A/648/A102
- Title:
- FR-type radio sources at 3GHz VLA-COSMOS
- Short Name:
- J/A+A/648/A102
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Radio active galactic nuclei (AGN) are traditionally separated into two Fanaro-Riley (FR) type classes, edge-brightened FRII sources or edge-darkened FRI sources. With the discovery of a plethora of radio AGN of different radio shapes, this dichotomy is becoming too simplistic in linking the radio structure to the physical properties of radio AGN, their hosts, and their environment. We probe the physical properties and large-scale environment of radio AGN in the faintest FR population to date, and link them to their radio structure. We use the VLA-COSMOS Large Project at 3GHz (3GHz VLA-COSMOS), with a resolution and sensitivity of 0.75" and 2.3Jy/beam to explore the FR dichotomy down to Jy levels. We classified objects as FRIs, FRIIs, or hybrid FRI/FRII based on the surface-brightness distribution along their radio structure. Our control sample was the jet-less/compact radio AGN objects (COM AGN), which show excess radio emission at 3GHz VLA-COSMOS exceeding what is coming from star-formation alone; this sample excludes FRs. The largest angular projected sizes of FR objects were measured by a machine-learning algorithm and also by hand, following a parametric approach to the FR classification. Eddington ratios were calculated using scaling relations from the X-rays, and we included the jet power by using radio luminosity as a probe. Furthermore, we investigated their host properties (star-formation ratio, stellar mass, morphology), and we explore their incidence within X-ray galaxy groups in COSMOS, and in the density fields and cosmic-web probes in COSMOS. Our sample is composed of 59 FRIIs, 32 FRI/FRIIs, 39 FRIs, and 1818 COM AGN at 0.03<=z<=6. On average, FR objects have similar radio luminosities (L_3GHz_~10^23^W/Hz/sr), spanning a range of 10^21-26^W/Hz/sr, and they lie at a median redshift of z~1. The median linear projected size of FRIIs is 106.6^238.2^_36.9_kpc, larger than that of FRI/FRIIs and FRIs by a factor of 2-3. The COM AGN have sizes smaller than 30kpc, with a median value of 1.7^4.7^_1.5_kpc. The median Eddington ratio of FRIIs is 0.006^0.007^_0.005_, a factor of 2.5 less than in FRIs and a factor of 2 higher than in FRI/FRII. When the jet power is included, the median Eddington ratios of FRII and FRI/FRII increase by a factor of 12 and 15, respectively. FRs reside in their majority in massive quenched hosts (M*>10^10.5^M_{sun}_), with older episodes of star-formation linked to lower X-ray galaxy group temperatures, suggesting radio-mode AGN quenching. Regardless of their radio structure, FRs and COM AGN are found in all types and density environments (group or cluster, filaments, field). By relating the radio structure to radio luminosity, size, Eddington ratio, and large-scale environment, we find a broad distribution and overlap of FR and COM AGN populations. We discuss the need for a different classification scheme, that expands the classic FR classification by taking into consideration the physical properties of the objects rather than their projected radio structure which is frequency-, sensitivity- and resolution-dependent. This point is crucial in the advent of current and future all-sky radio surveys.
- ID:
- ivo://CDS.VizieR/J/other/Ap/52.40
- Title:
- FSS galaxies in southern hemisphere
- Short Name:
- J/other/Ap/52.40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the properties of the 3838 galaxies that were monitored for SNe events, including newly determined morphologies and their DENIS and POSS-II/UKST I, 2MASS and DENIS J and K_s_ and 2MASS H magnitudes. We have compared 2MASS, DENIS and POSS-II/UKST IJK magnitudes in order to find possible systematic photometric shifts in the measurements. The DENIS and POSS-II/UKST I band magnitudes show large discrepancies (mean absolute difference of 0.4mag), mostly due to different spectral responses of the two instruments, with an important contribution (0.33mag rms) from the large uncertainties in the photometric calibration of the POSS-II and UKST photographic plates. In the other wavebands, the limiting near infrared magnitude, morphology, and inclination of the galaxies are the most influential factors which affect the determination of photometry of the galaxies. Nevertheless, no significant systematic differences have been found between of any pair of NIR magnitude measurements, except for a few percent of galaxies showing large discrepancies. This allows us to combine DENIS and 2MASS data for the J and K_s_ filters.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A94
- Title:
- FS Tau B two epoch spectro-imagery
- Short Name:
- J/A+A/627/A94
- Date:
- 23 Mar 2022 16:28:17
- Publisher:
- CDS
- Description:
- Herbig-Haro (HH) flows exhibit a large variety of morphological and kinematical structures such as bow shocks, Mach disks, and deflection shocks. Both proper motion (PM) and radial velocity investigations are essential to understand the physical nature of such structures. We investigate the kinematics and PM of spectrally separated structures in the FS Tau B HH flow. Collating these data makes it possible to understand the origin of these structures and to explain the unusual behavior of the jet. On the other hand, the study of emission profiles in the associated reflection nebulae allows us to consider the source of the outflow both from edge-on and pole-on points of view. We present the observational results obtained with the 6 m telescope at the Special Astrophysical Observatory of the Russian Academy of Sciences using the SCORPIO multimode focal reducer with a scanning Fabry-Perot interferometer. Two epochs of the observations of the FS Tau B region in H{alpha} emission (2001 and 2012) allowed us to measure the PM of the spectrally separated inner structures of the jet. In addition to already known emission structures in the FS Tau B system, we discover new features in the extended part of the jet and in the counter-jet. Moreover, we reveal a new HH knot in the HH 276 independent outflow system and point out its presumable source. In the terminal working surface of the jet, structures with different radial velocities have PMs of the same value. This result can be interpreted as the direct observation of bow-shock and Mach disk regions. A bar-like structure, located southwest from the source demonstrates zero PM and can be considered as one more example of deflection shock. An analysis of H{alpha} profiles in the reflection nebulae R1 and R3 indicates the uniqueness of this object, which can be studied in pole-on and edge-on directions simultaneously.
4858. FSVS Cluster Catalogue
- ID:
- ivo://CDS.VizieR/J/MNRAS/369/1334
- Title:
- FSVS Cluster Catalogue
- Short Name:
- J/MNRAS/369/1334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey (FSVS). The clusters have been identified using a fully automated, semiparametric technique based on a maximum likelihood approach applied to Voronoi tessellation, and enhanced by colour discrimination. The sample covers a wide range of richness, has a density of ~28 clusters/deg^2^, and spans a range of estimated redshifts of 0.05<z<0.9 with mean <z>=0.345. Assuming the presence of a cluster red sequence, the uncertainty of the estimated cluster redshifts is assessed to be {sigma}~0.03. Containing over 100 clusters with z>0.6, the catalogue contributes substantially to the current total of optically selected, intermediate-redshift clusters, and complements the existing, usually X-ray selected, samples. The FSVS fields are accessible for observation throughout the whole year, making them particularly suited for large follow-up programmes. The construction of this FSVS Cluster Catalogue completes a fundamental component of our continuing programmes to investigate the environments of quasars and the chemical evolution of galaxies. We publish here the list of all clusters with their basic parameters, and discuss some illustrative examples in more detail. The full FSVS Cluster Catalogue, together with images and lists of member galaxies etc., will be issued as part of the 'NOAO (National Optical Astronomy Observatories) data products', and accessible at http://www.noao.edu/dpp/ . We describe the format of these data and access to them.
- ID:
- ivo://CDS.VizieR/J/PASJ/72/43
- Title:
- FUGIN. VII. Galactic plane HI clouds
- Short Name:
- J/PASJ/72/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze molecular-gas formation in neutral atomic hydrogen (HI) clouds using the latest CO data, obtained from the FOREST (four-beam receiver system on the 45m telescope) unbiased Galactic plane imaging survey with the Nobeyama 45m telescope, and using HI data taken from the Very Large Array Galactic plane survey. We applied a dendrogram algorithm to the HI data cube to identify HI clouds, and we calculated the HI mass and molecular-gas mass by summing the CO line intensity within each HI cloud. On the basis of the results, we created a catalog of 5737 identified HI clouds with local standard of rest (LSR) velocity of VLSR<=-20km/s in galactic longitude and latitude ranges of 20{deg}<=l<=50{deg} and -1{deg}<=b<=1{deg}, respectively. We found that most of the HI clouds are distributed within a Galactocentric distance of 16kpc, and most of them are in the cold neutral medium phase. In addition, we determined that the high-mass end of the HI mass function is fitted well with a power-law function with an index of 2.3. Although two sequences of self-gravitating and diffuse clouds are expected to appear in the M_tot_-M_H2_ diagram according to previous works based on a plane-parallel model, the observational data show only a single sequence with large scattering within these two sequences. This implies that most of the clouds are mixtures of these two types of clouds. Moreover, we suggest the following scenario of molecular-gas formation: an HI-dominant cloud evolved with increasing H2 mass along a path of M_H2_{prop.to}M^2^_tot_ by collecting diffuse gas before reaching and moving along the curves of the two sequences.
- ID:
- ivo://CDS.VizieR/J/ApJ/854/73
- Title:
- Full-data results of HFF: galaxies z~6-9
- Short Name:
- J/ApJ/854/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UV luminosity functions of dropout galaxies at z~6-10 with the complete Hubble Frontier Fields data. We obtain a catalog of ~450 dropout-galaxy candidates (350, 66, and 40 at z~6-7, 8, and 9, respectively), with UV absolute magnitudes that reach ~-14mag, ~2 mag deeper than the Hubble Ultra Deep Field detection limits. We carefully evaluate number densities of the dropout galaxies by Monte Carlo simulations, including all lensing effects such as magnification, distortion, and multiplication of images as well as detection completeness and contamination effects in a self-consistent manner. We find that UV luminosity functions at z~6-8 have steep faint-end slopes, {alpha}~-2, and likely steeper slopes, {alpha}<~-2 at z~9-10. We also find that the evolution of UV luminosity densities shows a non-accelerated decline beyond z~8 in the case of M_trunc_=-15, but an accelerated one in the case of M_trunc_=-17. We examine whether our results are consistent with the Thomson scattering optical depth from the Planck satellite and the ionized hydrogen fraction Q_HII_ at z<~7 based on the standard analytic reionization model. We find that reionization scenarios exist that consistently explain all of the observational measurements with the allowed parameters of f_esc_=0.17_-0.03_^+0.07^ and M_trunc_>-14.0 for log{xi}_ion_/[erg^-1^Hz]=25.34, where f_esc_ is the escape fraction, Mtrunc is the faint limit of the UV luminosity function, and {xi}_ion_ is the conversion factor of the UV luminosity to the ionizing photon emission rate. The length of the reionization period is estimated to be {Delta}z=3.9_-1.6_^+2.0^ (for 0.1<Q_HII_<0.99), consistent with the recent estimate from Planck.