- ID:
- ivo://CDS.VizieR/J/ApJ/836/185
- Title:
- SEDs of the radio continuum from KINGFISHER
- Short Name:
- J/ApJ/836/185
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the spectral energy distribution (SED) of the radio continuum (RC) emission from the Key Insight in Nearby Galaxies Emitting in Radio (KINGFISHER) sample of nearby galaxies to understand the energetics and origin of this emission. Effelsberg multi-wavelength observations at 1.4, 4.8, 8.4, and 10.5GHz combined with archive data allow us, for the first time, to determine the mid-RC (1-10GHz, MRC) bolometric luminosities and further present calibration relations versus the monochromatic radio luminosities. The 1-10GHz radio SED is fitted using a Bayesian Markov Chain Monte Carlo technique leading to measurements for the nonthermal spectral index (S_{nu}_~{nu}^-{alpha}_nt_^) and the thermal fraction (f_th_) with mean values of {alpha}_nt_=0.97+/-0.16 (0.79+/-0.15 for the total spectral index) and f_th_=(10+/-9)% at 1.4GHz. The MRC luminosity changes over ~3 orders of magnitude in the sample, 4.3x10^2^L_{sun}_<MRC<3.9x10^5^L_{sun}_. The thermal emission is responsible for ~23% of the MRC on average. We also compare the extinction-corrected diagnostics of the star-formation rate (SFR) with the thermal and nonthermal radio tracers and derive the first star-formation calibration relations using the MRC radio luminosity. The nonthermal spectral index flattens with increasing SFR surface density, indicating the effect of the star-formation feedback on the cosmic-ray electron population in galaxies. Comparing the radio and IR SEDs, we find that the FIR-to-MRC ratio could decrease with SFR, due to the amplification of the magnetic fields in star-forming regions. This particularly implies a decrease in the ratio at high redshifts, where mostly luminous/star-forming galaxies are detected.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/759/6
- Title:
- SEDs of type I AGN in COSMOS. I. XMM-COSMOS
- Short Name:
- J/ApJ/759/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The "Cosmic Evolution Survey" (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM>2000km/s) AGNs with Magellan, SDSS, or VLT spectrum. The SEDs are corrected for Galactic extinction, broad emission line contributions, constrained variability, and host galaxy contribution. We present the mean SED and the dispersion SEDs after the above corrections in the rest-frame 1.4GHz to 40keV, and show examples of the variety of SEDs encountered. In the near-infrared to optical (rest frame ~8{mu}m-4000{AA}), the photometry is complete for the whole sample and the mean SED is derived from detections only. Reddening and host galaxy contamination could account for a large fraction of the observed SED variety.
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/577
- Title:
- Selected ALESS submm galaxies radio properties
- Short Name:
- J/MNRAS/442/577
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the radio properties of 870 {mu}m-selected submillimetre galaxies (SMGs), observed at high resolution with Atacama Large Millimeter Array (ALMA) in the Extended Chandra Deep Field South. From our initial sample of 76 ALMA SMGs, we detect 52 SMGs at >3{sigma} significance in Karl G. Jansky Very Large Array 1400MHz imaging, of which 35 are also detected at >3{sigma} in new 610MHz Giant Metre-Wave Radio Telescope imaging. Within this sample of radio-detected SMGs, we measure a median radio spectral index {alpha}_{610}_^{1400}^=-0.79+/-0.06, (with inter-quartile range {alpha}=[-1.16,-0.56]) and investigate the far-infrared/radio correlation via the parameter q_IR_, the logarithmic ratio of the rest-frame 8-1000{mu}m flux and monochromatic radio flux. Our median q_IR_=2.56+/-0.05 (inter-quartile range q_IR_=[2.42,2.78]) is higher than that typically seen in single-dish 870{mu}m-selected sources (q_IR_~2.4), which may reflect the fact that our ALMA-based study is not biased to radio-bright counterparts, as previous samples were. Finally, we search for evidence that q_IR_ and {alpha} evolve with age in a codependent manner, as predicted by starburst models: the data populate the predicted region of parameter space, with the stellar mass tending to increase along tracks of q_IR_ versus {alpha} in the direction expected, providing the first observational evidence in support of these models.
- ID:
- ivo://CDS.VizieR/J/A+A/296/727
- Title:
- Semiregular variables H2O maser
- Short Name:
- J/A+A/296/727
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 107 semiregular variables of spectral type M have been observed in the H2O 6(16)-5(23) line at 22.235GHz with the 100m Effelsberg radio telescope and maser emission has been detected in 23 objects, of which 10 are new detections.
- ID:
- ivo://CDS.VizieR/J/A+A/620/A62
- Title:
- Serpens filament emission lines datacubes
- Short Name:
- J/A+A/620/A62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Serpens filament, as one of the nearest infrared dark clouds, is regarded as a pristine filament at a very early evolutionary stage of star formation. In order to study its molecular content and dynamical state, we mapped this filament in seven species including C^18^O, HCO^+^, HNC, HCN, N_2_H^+^, CS, and CH_3_OH. Among them, HCO^+^, HNC, HCN, and CS show self-absorption, while C^18^O is most sensitive to the filamentary structure. A kinematic analysis demonstrates that this filament forms a velocity-coherent (trans-)sonic structure, a large part of which is one of the most quiescent regions in the Serpens cloud. Widespread C^18^O depletion is found throughout the Serpens filament. Based on the Herschel dust-derived H_2_ column density map, the line mass of the filament is 36-41~M_{sun}_/pc, and its full width at half maximum width is 0.17+/-0.01pc, while its length is ~1.6pc. The inner radial column density profile of this filament can be well fitted with a Plummer profile with an exponent of 2.2+/-0.1, a scale radius of 0.018+/-0.003pc and a central density of (4.0+/-0.8)x10^4^cm^-3^. The Serpens filament appears to be slightly supercritical. The widespread blue-skewed HNC and CS line profiles and HCN hyperfine line anomalies across this filament indicate radial infall in parts of the Serpens filament. C^18^O velocity gradients also indicate accretion flows along the filament. The velocity and density structures suggest that such accretion flows are likely due to a longitudinal collapse parallel to the filament's long axis. Both the radial infall rate and the longitudinal accretion rate along the Serpens filament are lower than all previously reported values in other filaments. This indicates that the Serpens filament lies at an early evolutionary stage when collapse has just begun, or that thermal and non-thermal support are effective in providing support against gravity.
- ID:
- ivo://CDS.VizieR/J/A+AS/116/157
- Title:
- SEST obs. of extragalactic radiosources
- Short Name:
- J/A+AS/116/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Flux densities of 155 extragalactic radio sources observed with the SEST telescope at 3mm and 1.3mm are presented. The observations were performed from October 1987 to June 1994. In addition to the flux density tables we have plotted the flux density curves for some of the most frequently observed sources.
1537. Seven-year WMAP catalog
- ID:
- ivo://CDS.VizieR/J/ApJS/192/15
- Title:
- Seven-year WMAP catalog
- Short Name:
- J/ApJS/192/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination outside of the updated (KQ85y7) foreground mask. We place a 15uK upper bound on rms foreground contamination in the cleaned maps used for cosmological analysis. Further, the cleaning process requires only three power-law foregrounds outside of the mask. We find no evidence for polarized foregrounds beyond those from soft (steep-spectrum) synchrotron and thermal dust emission; in particular we find no indication in the polarization data of an extra "haze" of hard synchrotron emission from energetic electrons near the Galactic center. We provide an updated map of the cosmic microwave background (CMB) using the internal linear combination method, updated foreground masks, and updates to point source catalogs using two different techniques. With additional years of data, we now detect 471 point sources using a five-band technique and 417 sources using a three-band CMB-free technique. In total there are 62 newly detected point sources, a 12% increase over the five-year release.
- ID:
- ivo://CDS.VizieR/J/A+A/643/A127
- Title:
- 5 Seyferts reduced CO(2-1) cubes
- Short Name:
- J/A+A/643/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58Mpc) Seyfert galaxies. The resolution of ~0.3-0.8 (~30-100pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (~100pc) and up to radial distances of ~900pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (~100pc) and circumnuclear (~650pc) scales in the range from 10^6^ to 10^7^M_{sun}_ and from 10^7^ to 10^8^M_{sun}_, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry.
- ID:
- ivo://CDS.VizieR/J/A+A/621/A119
- Title:
- SgrA* and NRAS530 86GHz images
- Short Name:
- J/A+A/621/A119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The compact radio source Sagittarius A* (Sgr A*) in the Galactic centre is the primary supermassive black hole candidate. General relativistic magnetohydrodynamical (GRMHD) simulations of the accretion flow around Sgr A* predict the presence of sub-structure at observing wavelengths of ~3mm and below (frequencies of 86GHz and above). For very long baseline interferometry (VLBI) observations of Sgr A* at this frequency the blurring effect of interstellar scattering becomes sub-dominant, and arrays such as the high sensitivity array (HSA) and the global mm-VLBI array (GMVA) are now capable of resolving potential sub-structure in the source. Such investigations help to improve our understanding of the emission geometry of the mm-wave emission of Sgr A*, which is crucial for constraining theoretical models and for providing a background to interpret 1mm VLBI data from the Event Horizon Telescope (EHT). Following the closure phase analysis in our first paper, which indicates asymmetry in the 3 mm emission of Sgr A*, here we have used the full visibility information to check for possible sub-structure. We extracted source size information from closure amplitude analysis, and investigate how this constrains a combined fit of the size-frequency relation and the scattering law for Sgr A*. We performed high-sensitivity VLBI observations of Sgr A* at 3mm using the Very Long Baseline Array (VLBA) and the Large Millimeter Telescope (LMT) in Mexico on two consecutive days in May 2015, with the second epoch including the Greenbank Telescope (GBT). We confirm the asymmetry for the experiment including GBT. Modelling the emission with an elliptical Gaussian results in significant residual flux of ~10mJy in south-eastern direction. The analysis of closure amplitudes allows us to precisely constrain the major and minor axis size of the main emission component. We discuss systematic effects which need to be taken into account. We consider our results in the context of the existing body of size measurements over a range of observing frequencies and investigate how well-constrained the size-frequency relation is by performing a simultaneous fit to the scattering law and the size-frequency relation. We find an overall source geometry that matches previous findings very closely, showing a deviation in fitted model parameters less than 3% over a time scale of weeks and suggesting a highly stable global source geometry over time. The reported sub-structure in the 3mm emission of Sgr A* is consistent with theoretical expectations of refractive noise on long baselines. However, comparing our findings with recent results from 1mm and 7mm VLBI observations, which also show evidence for east-west asymmetry, we cannot exclude an intrinsic origin. Confirmation of persistent intrinsic substructure will require further VLBI observations spread out over multiple epochs.
- ID:
- ivo://CDS.VizieR/J/other/Sci/348.413
- Title:
- Sgr A East SNR multiwavelength images
- Short Name:
- J/other/Sci/348.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dust formation in supernova ejecta is currently the leading candidate to explain the large quantities of dust observed in the distant, early universe. However, it is unclear whether the ejecta-formed dust can survive the hot interior of the supernova remnant (SNR). We present infrared observations of ~0.02 solar masses of warm (~100 kelvin) dust seen near the center of the ~10,000-year-old Sagittarius A East SNR at the Galactic center. Our findings indicate the detection of dust within an older SNR that is expanding into a relatively dense surrounding medium (electron density ~10^3^ centimeters^-3^) and has survived the passage of the reverse shock. The results suggest that supernovae may be the dominant dust-production mechanism in the dense environment of galaxies of the early universe.
