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2331. 1.3mm VLBI detections of M87
ID:
ivo://CDS.VizieR/J/other/Sci/338.355
Title:
1.3mm VLBI detections of M87
Short Name:
J/other/Sci/338.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Approximately 10% of active galactic nuclei exhibit relativistic jets, which are powered by the accretion of matter onto supermassive black holes. Although the measured width profiles of such jets on large scales agree with theories of magnetic collimation, the predicted structure on accretion disk scales at the jet launch point has not been detected. We report radio interferometry observations, at a wavelength of 1.3 millimeters, of the elliptical galaxy M87 that spatially resolve the base of the jet in this source. The derived size of 5.5+/-0.4 Schwarzschild radii is significantly smaller than the innermost edge of a retrograde accretion disk, suggesting that the M87 jet is powered by an accretion disk in a prograde orbit around a spinning black hole.
2332. mm-wave size study of ALMA submm galaxies
ID:
ivo://CDS.VizieR/J/ApJ/849/L36
Title:
mm-wave size study of ALMA submm galaxies
Short Name:
J/ApJ/849/L36
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the study of the far-infrared (IR) sizes of submillimeter galaxies (SMGs) in relation to their dust-obscured star formation rate (SFR) and active galactic nuclei (AGN) presence, determined using mid-IR photometry. We determined the millimeter-wave ({lambda}_obs_=1100um) sizes of 69 Atacama Large Millimeter/submillimeter Array (ALMA)-identified SMGs, selected with >=10{sigma} confidence on ALMA images (F_1100um_=1.7-7.4mJy). We found that all of the SMGs are located above an avoidance region in the size-flux plane, as expected by the Eddington limit for star formation. In order to understand what drives the different millimeter-wave sizes in SMGs, we investigated the relation between millimeter-wave size and AGN fraction for 25 of our SMGs at z=1-3. We found that the SMGs for which the mid-IR emission is dominated by star formation or AGN have extended millimeter-sizes, with respective median R_c,e_=1.6_-0.21_^+0.34^ and 1.5_-0.24_^+0.93^kpc. Instead, the SMGs for which the mid-IR emission corresponds to star-forming/AGN composites have more compact millimeter-wave sizes, with median R_c,e_=1.0_-0.20_^+0.20^kpc. The relation between millimeter-wave size and AGN fraction suggests that this size may be related to the evolutionary stage of the SMG. The very compact sizes for composite star-forming/AGN systems could be explained by supermassive black holes growing rapidly during the SMG coalescing, star-formation phase.
2333. M100 (NGC4321) HII region IRAC photometry
ID:
ivo://CDS.VizieR/J/A+A/553/A54
Title:
M100 (NGC4321) HII region IRAC photometry
Short Name:
J/A+A/553/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
We systematically study the relations between the H{alpha} luminosity and the near-IR luminosity and temperature of a set of selected HII regions in the disc of M100. By using the technique of cross-reference between the optical H{alpha} image (the catalogue of HII regions in M100 and the Spitzer IRAC images, we locate the selected HII regions in the IRAC image frames. By using the chi-squared non-linear fitting technique, we estimate the IRAC-3-band colour temperature T_col(IRAC)_ of selected HII regions, and calculate their near-IR luminosities.
2334. Modeling starburst SEDs
ID:
ivo://CDS.VizieR/J/ApJ/619/755
Title:
Modeling starburst SEDs
Short Name:
J/ApJ/619/755
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we combine the stellar spectral synthesis code STARBURST99, the nebular modeling code MAPPINGS IIIq, a one-dimensional dynamical evolution model of H II regions around massive clusters of young stars, and a simplified model of synchrotron emissivity to produce purely theoretical self-consistent synthetic spectral energy distributions (SEDs) for (solar metallicity) starbursts lasting ~10^8^yr. These SEDs extend from the Lyman limit to beyond 21cm. We present detailed SED fits to Arp 220 and NGC 6240, and we give the predicted colors for starburst galaxies derived from our models for the IRAS and the Spitzer Space Telescope MIPS and IRAC instruments. Our models reproduce the spread in observed colors of starburst galaxies. Finally, we present absolute calibrations to convert observed fluxes into star formation rates in the UV (GALEX), at optical wavelengths (H), and in the IR (IRAS or Spitzer).
2335. Models for massive low-Z rotating single stars
ID:
ivo://CDS.VizieR/J/A+A/581/A15
Title:
Models for massive low-Z rotating single stars
Short Name:
J/A+A/581/A15
Date:
21 Oct 2021
Publisher:
CDS
Description:
A good understanding of low-metallicity environments requires a detailed theoretical comprehension of the evolution of their massive stars. Our models can be used to interpret observations of local star-forming dwarf galaxies and high-redshift galaxies, as well as the metal-poor components of our Milky Way and its globular clusters.
2336. MOIRCS Deep Survey deep and wide catalogs
ID:
ivo://CDS.VizieR/J/PASJ/63/S379
Title:
MOIRCS Deep Survey deep and wide catalogs
Short Name:
J/PASJ/63/S379
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep J-, H-, and Ks-band imaging data of the MOIRCS Deep Survey (MODS), which was carried out with the Multi-Object Infrared Camera and Spectrograph (MOIRCS) mounted on the Subaru Telescope in the GOODS-North region. The data reach 5{sigma} total limiting magnitudes for point sources of J=23.9, H=22.8, and Ks=22.8 (Vega magnitude) over 103 arcmin^2^ (wide field). In 28 arcmin^2^ of the survey area, which is an ultra-deep field of the MODS (deep field), the data reach 5{sigma} depths of J=24.8, H=23.4, and Ks=23.8. The spatial resolutions of the combined images are FWHM~0.6" and ~0.5" for the wide and deep fields in all bands, respectively. Combining the MODS data with the multi-wavelength public data taken with the HST, Spitzer, and other ground-based telescopes in the GOODS field, we constructed a multi-wavelength photometric catalog of Ks-selected sources.
2337. MOIRCS Deep Survey. VII.
ID:
ivo://CDS.VizieR/J/PASJ/63/S363
Title:
MOIRCS Deep Survey. VII.
Short Name:
J/PASJ/63/S363
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigated rest-frame near-infrared (NIR) morphologies of a sample of 139 galaxies with Ms>=1x10^109M_{sun}_ at z=0.8-1.2 in the GOODS-North field using our deep NIR imaging data (MOIRCS Deep Survey, MODS). We focused on Luminous Infrared Galaxies (LIRGs), which dominate a high star formation rate (SFR) density at z~1, in a sample identified by cross-correlating with the Spitzer/MIPS 24mum source catalog. We performed two-dimensional light profile fittings of z~1 galaxies in the Ks-band (rest-frame J-band) with a single-component Sersic model.
2338. MOJAVE. XI. Spectral distributions
ID:
ivo://CDS.VizieR/J/AJ/147/143
Title:
MOJAVE. XI. Spectral distributions
Short Name:
J/AJ/147/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained milliarcsecond-scale spectral index distributions for a sample of 190 extragalactic radio jets through the Monitoring of Jets in Active Galactic Nuclei with the VLBA Experiments (MOJAVE) project. The sources were observed in 2006 at 8.1, 8.4, 12.1, and 15.4GHz, and we have determined spectral index maps between 8.1 and 15.4GHz to study the four-frequency spectrum in individual jet features. We have performed detailed simulations to study the effects of image alignment and (u, v)-plane coverage on the spectral index maps to verify our results. We use the spectral index maps to study the spectral index evolution along the jet and determine the spectral distributions in different locations of the jets. The core spectral indices are on average flat with a mean value of +0.22+/-0.03 for the sample, while the jet spectrum is in general steep with a mean index of -1.04+/-0.03. A simple power-law fit is often inadequate for the core regions, as expected if the cores are partially self-absorbed. The overall jet spectrum steepens at a rate of about -0.001 to -0.004 per deprojected parsec when moving further out from the core with flat spectrum radio quasars having significantly steeper spectra (mean -1.09+/-0.04) than the BL Lac objects (mean -0.80+/-0.05). However, the spectrum in both types of objects flattens on average by ~0.2 at the locations of the jet components indicating particle acceleration or density enhancements along the jet. The mean spectral index at the component locations of -0.81+/-0.02 corresponds to a power-law index of ~2.6 for the electron energy distribution. We find a significant trend that jet components with linear polarization parallel to the jet (magnetic field perpendicular to the jet) have flatter spectra, as expected for transverse shocks. Compared to quasars, BL Lacs have more jet components with perpendicular magnetic field alignment, which may explain their generally flatter spectra. The overall steepening of the spectra with distance can be explained with radiative losses if the jets are collimating or with the evolution of the high-energy cutoff in the electron spectrum if the jets are conical. This interpretation is supported by a significant correlation with the age of the component and the spectral index, with older components having steeper spectra.
2339. MOJAVE XIV. AGN jet shapes & opening angles
ID:
ivo://CDS.VizieR/J/MNRAS/468/4992
Title:
MOJAVE XIV. AGN jet shapes & opening angles
Short Name:
J/MNRAS/468/4992
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 15 GHz stacked VLBA images of 373 jets associated with active galactic nuclei (AGN) having at least 5 observing epochs within a 20yr time interval 1994-2015 from the MOJAVE programme and/or its precursor, the 2 cm VLBA Survey. These data are supplemented by 1.4 GHz single-epoch VLBA observations of 135 MOJAVE AGNs to probe larger scale jet structures. The typical jet geometry is found to be close to conical on scales from hundreds to thousands of parsecs, while a number of galaxies show quasi-parabolic streamlines on smaller scales. A true jet geometry in a considerable fraction of AGNs appears only after stacking epochs over several years. The jets with significant radial accelerated motion undergo more active collimation. We have analyzed total intensity jet profiles transverse to the local jet ridgeline and derived both apparent and intrinsic opening angles of the flows, with medians of 21.5{deg} and 1.3{deg}, respectively. The Fermi LAT-detected gamma-ray AGNs in our sample have, on average, wider apparent and narrower intrinsic opening angle, and smaller viewing angle than non LAT-detected AGNs. We have established a highly significant correlation between the apparent opening angle and gamma-ray luminosity, driven by Doppler beaming and projection effects.
2340. MOJAVE. XVII. Parsec-scale jet kinematics of AGNs
ID:
ivo://CDS.VizieR/J/ApJ/874/43
Title:
MOJAVE. XVII. Parsec-scale jet kinematics of AGNs
Short Name:
J/ApJ/874/43
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a parsec-scale jet kinematics study of 409 bright radio-loud active galactic nuclei (AGNs) based on 15GHz Very Long Baseline Array (VLBA) data obtained between 1994 August 31 and 2016 December 26 as part of the 2cm VLBA survey and Monitoring Of Jets in Active galactic nuclei with VLBA Experiments (MOJAVE) programs. We tracked 1744 individual bright features in 382 jets over at least 5 epochs. A majority (59%) of the best-sampled jet features showed evidence of accelerated motion at the >3{sigma} level. Although most features within a jet typically have speeds within ~40% of a characteristic median value, we identified 55 features in 42 jets that had unusually slow pattern speeds, nearly all of which lie within 4pc (100pc deprojected) of the core feature. Our results, combined with other speeds from the literature, indicate a strong correlation between apparent jet speed and synchrotron peak frequency, with the highest jet speeds being found only in low-peaked AGNs. Using Monte Carlo simulations, we find best-fit parent population parameters for a complete sample of 174 quasars above 1.5Jy at 15GHz. Acceptable fits are found with a jet population that has a simple unbeamed power-law luminosity function incorporating pure luminosity evolution and a power-law Lorentz factor distribution ranging from 1.25 to 50 with slope -1.4+/-0.2. The parent jets of the brightest radio quasars have a space density of 261+/-19Gpc^-3^ and unbeamed 15GHz luminosities above ~10^24.5^W/Hz, consistent with FRII class radio galaxies.

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