- ID:
- ivo://CDS.VizieR/J/ApJ/816/L14
- Title:
- Tully-Fisher relation in disk galaxies from SPARC
- Short Name:
- J/ApJ/816/L14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In a {Lambda} cold dark matter ({Lambda}CDM) cosmology, the baryonic Tully-Fisher relation (BTFR) is expected to show significant intrinsic scatter resulting from the mass-concentration relation of dark matter halos and the baryonic-to-halo mass ratio. We study the BTFR using a sample of 118 disk galaxies (spirals and irregulars) with data of the highest quality: extended HI rotation curves (tracing the outer velocity) and Spitzer photometry at 3.6{mu}m (tracing the stellar mass). Assuming that the stellar mass-to-light ratio ({Upsilon}_*_) is nearly constant at 3.6{mu}m, we find that the scatter, slope, and normalization of the BTFR systematically vary with the adopted {Upsilon}_*_. The observed scatter is minimized for {Upsilon}_*_>~0.5M_{Sun}_/L_{Sun}_, corresponding to nearly maximal disks in high-surface-brightness galaxies and BTFR slopes close to ~4. For any reasonable value of {Upsilon}_*_, the intrinsic scatter is ~0.1dex, below general {Lambda}CDM expectations. The residuals show no correlations with galaxy structural parameters (radius or surface brightness), contrary to the predictions from some semi-analytic models of galaxy formation. These are fundamental issues for {Lambda}CDM cosmology.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/647/A152
- Title:
- Tully-Fisher relation in MAGIC groups
- Short Name:
- J/A+A/647/A152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxies in dense environments are subject to interactions and mechanisms that directly affect their evolution by lowering their gas fractions and consequently reducing their star-forming capacity earlier than their isolated counterparts. The aim of our project is to get new insights into the role of environment in the stellar and baryonic content of galaxies using a kinematic approach, through the study of the Tully-Fisher relation (TFR). We study a sample of galaxies in eight groups, over-dense by a factor larger than 25 with respect to the average projected density, spanning a redshift range of 0.5<z<0.8 and located in ten pointings of the MAGIC MUSE Guaranteed Time Observations program. We perform a morpho-kinematics analysis of this sample and set up a selection based on galaxy size, [OII]{lambda}{lambda}3727,3729 emission line doublet signal-to-noise ratio, bulge-to-disk ratio, and nuclear activity to construct a robust kinematic sample of 67 star-forming galaxies. We show that this selection considerably reduces the number of outliers in the TFR, which are predominantly dispersion-dominated galaxies. Similar to other studies, we find that including the velocity dispersion in the velocity budget mainly affects galaxies with low rotation velocities, reduces the scatter in the relation, increases its slope, and decreases its zero-point. Including gas masses is more significant for low-mass galaxies due to a larger gas fraction, and thus decreases the slope and increases the zero-point of the relation. Our results suggest a significant offset of the TFR zero-point between galaxies in low- and high-density environments, regardless of the kinematics estimator used. This can be interpreted as a decrease in either stellar mass by ~0.05-0.3dex or an increase in rotation velocity by ~0.02-0.06dex for galaxies in groups, depending on the samples used for comparison. We also studied the stellar and baryon mass fractions within stellar disks and found they both increase with stellar mass, the trend being more pronounced for the stellar component alone. These fractions do not exceed 50%. We show that this evolution of the TFR is consistent either with a decrease in star formation or with a contraction of the mass distribution due to the environment. These two effects probably act together, with their relative contribution depending on the mass regime.
- ID:
- ivo://CDS.VizieR/J/MNRAS/377/806
- Title:
- Tully-Fisher relation of DEEP2 galaxies
- Short Name:
- J/MNRAS/377/806
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Local and intermediate redshift (z~0.5) galaxy samples obey well correlated relations between the stellar population luminosity and maximal galaxy rotation that define the TullyFisher (TF) relation. Consensus is starting to be reached on the TF relation at z~0.5, but work at significantly higher redshifts is even more challenging, and has been limited by small galaxy sample sizes, the intrinsic scatter of galaxy properties, and increasing observational uncertainties. We present here the TF measurements of 41 galaxies at relatively high redshift, spectroscopically observed with the Keck/DEIMOS instrument by the DEEP2 project, a survey which will eventually offer a large galaxy sample of the greatest depth and number yet achieved towards this purpose. The first-look sample analyzed here has a redshift range of 0.75<z<1.3 with <z>=0.85 and an intrinsic magnitude range from M_B_ of -22.66 to -20.57 (Vega). We find that compared to local fiducial samples, a brightening of 1.5mag is observed, and consistent with passive evolutionary models.
14464. Tuorla Quasar Monitoring
- ID:
- ivo://CDS.VizieR/J/A+AS/143/357
- Title:
- Tuorla Quasar Monitoring
- Short Name:
- J/A+AS/143/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observations presented in table 3 were made by using the 1.03m Dall-Kirkham-type telescope (f/8.45) of Tuorla Observatory with a SBIG ST-8 CCD-camera and a standard V-band filter. Table 4 includes data (B-, V- , and R-bands) observed at the Nordic Optical Telescope (NOT) on La Palma. Corrections for dark-current effects, additive effects (bias) and multiplicative effects (flatfield) were applied. Due to the relatively small field of view of the telescope separate frames of comparison stars were exposed for Mrk 421 and 4C 29.45. For the other objects normal differential photometry methods were applied. Exposure times with the Tuorla 1.03 meter telescope were between 60 and 240 seconds for objects brighter than 16 mag. For fainter objects, we have combined several exposures to achieve a sufficiently high signal to noise ratio.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A32
- Title:
- Turin-SyCAT, Seyferts multifrequency catalog
- Short Name:
- J/A+A/659/A32
- Date:
- 02 Mar 2022 06:48:51
- Publisher:
- CDS
- Description:
- We present the first release of Turin-SyCAT, a multifrequency catalog of Seyfert galaxies. We selected Seyfert galaxies considering criteria based on radio, infrared, and optical properties and starting from sources belonging to hard X-ray catalogs and surveys. We visually inspected optical spectra available for all selected sources. We adopted homogeneous and stringent criteria in the source selection aiming at reducing the possible contamination from other source classes. Our final catalog includes 351 Seyfert galaxies distinguished in 233 type 1 and 118 type 2. Type 1 Seyfert galaxies appear to have mid-IR colors similar to blazars, but are distinguished from them by their radio-loudness. Additionally, Seyfert 2 galaxies have mid-IR colors more similar to quasars than BL Lac objects. As expected from their spectral properties, type 1 and 2 Seyfert galaxies show a clear distinction when using the u-r color. Finally, we found a tight correlation between the mid-IR fluxes at both 12 and 22 um (i.e., F12 and F22, respectively) and hard X-ray fluxes between 15 and 150 keV. Both Seyfert types appear to follow the same trend and share similar values of the ratios of F12 and F22 to FHX in agreement with expectations of the AGN unification scenario. As future perspectives, the Turin-SyCAT will then be used to search for heavily obscured Seyfert galaxies among unidentified hard X-ray sources, given the correlation between mid-IR and hard X-rays, and to investigate their large-scale environments.
- ID:
- ivo://CDS.VizieR/J/A+A/592/A49
- Title:
- TW Hya CO (2-1), CN (2-1) and CS (5-4) data cubes
- Short Name:
- J/A+A/592/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to obtain a spatially resolved measurement of velocity dispersions in the disk of TW Hya. We obtained images with high spatial and spectral resolution of the CO J=2-1, CN N=2-1 and CS J=5-4 emission with ALMA in Cycle 2. The radial distribution of the turbulent broadening was derived with two direct methods and one modelling approach. The first method requires a single transition and derives T_ex_ directly from the line profile, yielding a v_turb_. The second method assumes that two different molecules are co-spatial, which allows using their relative line widths for calculating T_kin_ and v_turb_. Finally we fitted a parametric disk model in which the physical properties of the disk are described by power laws, to compare our direct methods with previous values.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A46
- Title:
- TW Hydrae association with X-shooter
- Short Name:
- J/A+A/632/A46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Measurements of the protoplanetary disk frequency in young star clusters of different ages indicate disk lifetimes <10Myr. However, our current knowledge of how mass accretion in young stars evolves over the lifespans of disks is subject to many uncertainties, especially at the lower stellar masses. In this study, we investigate ongoing accretion activity in the TW Hydrae association (TWA), the closest association of pre-main sequence stars with active disks. The age (8-10Myr) and the proximity of the TWA render it an ideal target to probe the final stages of disk accretion down to brown dwarf masses. The study is based on homogeneous spectroscopic data from 300nm to 2500nm, obtained synoptically with X-shooter, which allows simultaneous derivation of individual extinction, stellar parameters, and accretion parameters for each star. The continuum excess emission diagnostics is used to estimate the accretion luminosities and mass accretion rates of our disk-bearing targets, and the shape and intensity of permitted and forbidden emission lines are analyzed to probe the physics of the star-disk interaction environment.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/4073
- Title:
- Two catalogues of superclusters
- Short Name:
- J/MNRAS/445/4073
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two new catalogues of superclusters of galaxies out to a redshift of z=0.15, based on the Abell/ACO cluster redshift compilation maintained by one of us (HA). The first of these catalogues, the all-sky Main SuperCluster Catalogue (MSCC), is based on only the rich (A-) Abell clusters, and the second one, the Southern SuperCluster Catalogue (SSCC), covers declinations {delta}<-17{deg} and includes the supplementary Abell S-clusters. A tunable Friends-of-Friends algorithm was used to account for the cluster density decreasing with redshift and for different selection functions in distinct areas of the sky. We present the full list of Abell clusters used, together with their redshifts and supercluster memberships and including the isolated clusters. The SSCC contains about twice the number of superclusters than MSCC for {delta}<-17{deg}, which we found to be due to (1) new superclusters formed by A-clusters in their cores and surrounded by S-clusters (50%), (2) new superclusters formed by S-clusters only (40%), (3) redistribution of member clusters by fragmentation of rich (multiplicity m>15) superclusters (8%), and (4) new superclusters formed by the connection of A-clusters through bridges of S-clusters (2%). Power-law fits to the cumulative supercluster multiplicity function yield slopes of {alpha}=-2.0 and {alpha}=-1.9 for MSCC and SSCC, respectively. This power-law behaviour is in agreement with the findings for other observational samples of superclusters, but not with that of catalogues based on cosmological simulations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/339/913
- Title:
- Two distant massive clusters of galaxies
- Short Name:
- J/MNRAS/339/913
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the radio, optical, and X-ray properties of two newly discovered, very X-ray luminous, distant clusters of galaxies. Both systems were noted as cluster candidates in a cross-correlation of data from the WENSS (<VIII/162>) radio survey and the ROSAT All-Sky Survey (<IX/10>). Follow-up observations performed by us and the Massive Cluster Survey (MACS) team confirmed both sources as distant galaxy clusters. The first cluster, MACS J0717.5+3745 at a redshift of z=0.5548, contains a very extended, steep-spectrum radio source offset from the cluster core, making it the most distant radio relic known. The second cluster, MACS J1621.3+3810 at z=0.465, is a strong cooling flow with a relatively weak central radio source. We present results from ROSAT High-Resolution Imager (HRI, Cat. <IX/28>) observations of both clusters as well as from optical imaging and VLA radio interferometry observations. Our discoveries demonstrate that distant clusters can be efficiently identified in a relatively shallow X-ray survey, that radio/X-ray selection is efficient, and that both cooling flow and non-cooling flow clusters are selected.
14470. Two-Micron Sky Survey (TMSS)
- ID:
- ivo://CDS.VizieR/II/2B
- Title:
- Two-Micron Sky Survey (TMSS)
- Short Name:
- II/2B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog, giving sources of emission in the 2.2-micrometer region for more than 5000 stars, represents a systematic survey of the Northern Hemisphere for stars brighter than third magnitude. The survey was carried out with a telescope at Mount Wilson, California, having a 62-inch diameter and an f/l aluminized epoxy mirror mounted equatorially. Radiation at an effective wavelength of 2.2 micrometers was detected by a lead sulfide photoconductive cell cooled by liquid nitrogen. In addition to the 2.2-micrometer detector array, radiation at an effective wavelength of 0.84 micrometers was detected by a simple silicon photovoltaic cell. The catalog includes right ascension and declination (B1950.0), K and I magnitudes, number of measurements, V magnitude, spectral types, cross identifications to the numbering systems of the General Catalogue, the Durchmusterung catalogs, the Bright Star Catalogue, and star names.
