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2991. Radiation fields of the Milky Way
ID:
ivo://CDS.VizieR/J/MNRAS/470/2539
Title:
Radiation fields of the Milky Way
Short Name:
J/MNRAS/470/2539
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide a library for the ultraviolet - submillimetre (submm) interstellar radiation fields (ISRFs) of the Milky Way (MW), derived from modelling COBE, IRAS and Planck maps of the all-sky emission in the near-, mid-, far-infrared and submm. The library was produced using the axisymmetric radiative transfer model that we have previously implemented to model the panchromatic spectral energy distributions (SEDs) of star-forming galaxies in the nearby universe, but with a new methodology allowing for optimization of the radial and vertical geometry of stellar emissivity and dust opacity, as deduced from the highly resolved emission seen from the vantage point of the Sun.
2992. Radiative contribution from stripped stars
ID:
ivo://CDS.VizieR/J/A+A/629/A134
Title:
Radiative contribution from stripped stars
Short Name:
J/A+A/629/A134
Date:
21 Oct 2021
Publisher:
CDS
Description:
Stars stripped of their envelopes from interaction with a binary companion emit a significant fraction of their radiation as ionizing photons. They are potentially important stellar sources of ionizing radiation, however, they are still often neglected in spectral synthesis simulations or simulations of stellar feedback. In anticipating the large datasets of galaxy spectra from the upcoming James Webb Space Telescope, we modeled the radiative contribution from stripped stars by using detailed evolutionary and spectral models. We estimated their impact on the integrated spectra and specifically on the emission rates of HI-, HeI-, and HeII-ionizing photons from stellar populations. We find that stripped stars have the largest impact on the ionizing spectrum of a population in which star formation halted several Myr ago. In such stellar populations, stripped stars dominate the emission of ionizing photons, mimicking a younger stellar population in which massive stars are still present. Our models also suggest that stripped stars have harder ionizing spectra than massive stars. The additional ionizing radiation, with which stripped stars contribute affects observable properties that are related to the emission of ionizing photons from stellar populations. In co-eval stellar populations, the ionizing radiation from stripped stars increases the ionization parameter and the production efficiency of hydrogen ionizing photons. They also cause high values for these parameters for about ten times longer than what is predicted for massive stars. The effect on properties related to non-ionizing wavelengths is less pronounced, such as on the ultraviolet continuum slope or stellar contribution to emission lines. However, the hard ionizing radiation from stripped stars likely introduces a characteristic ionization structure of the nebula, which leads to the emission of highly ionized elements such as O^2+^ and C^3+^. We, therefore, expect that the presence of stripped stars affects the location in the BPT diagram and the diagnostic ratio of OIII to OII nebular emission lines. Our models are publicly available through CDS database and on the STARBURST99 website.
2993. Radio-AGN feedback for 0.5<z<1
ID:
ivo://CDS.VizieR/J/MNRAS/445/955
Title:
Radio-AGN feedback for 0.5<z<1
Short Name:
J/MNRAS/445/955
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the first measurement of the radio luminosity function of 'jet-mode' (radiatively inefficient) radio-AGN out to z=1, in order to investigate the cosmic evolution of radio-AGN feedback. Eight radio source samples are combined to produce a catalogue of 211 radio-loud AGN with 0.5<z<1.0, which are spectroscopically classified into jet-mode and radiative-mode (radiatively efficient) AGN classes. Comparing with large samples of local radio-AGN from the Sloan Digital Sky Survey, the cosmic evolution of the radio luminosity function of each radio-AGN class is independently derived. Radiative-mode radio-AGN show an order of magnitude increase in space density out to z~1 at all luminosities, consistent with these AGN being fuelled by cold gas. In contrast, the space density of jet-mode radio-AGN decreases with increasing redshift at low radio luminosities (L_1.4GHz_<~10^24^W/Hz) but increases at higher radio luminosities. Simple models are developed to explain the observed evolution. In the best-fitting models, the characteristic space density of jet-mode AGN declines with redshift in accordance with the declining space density of massive quiescent galaxies, which fuel them via cooling of gas in their hot haloes. A time delay of 1.5-2Gyr may be present between the quenching of star formation and the onset of jet-mode radio-AGN activity. The behaviour at higher radio luminosities can be explained either by an increasing characteristic luminosity of jet-mode radio-AGN activity with redshift (roughly as (1+z)^3^) or if the jet-mode radio-AGN population also includes some contribution of cold-gas-fuelled sources seen at a time when their accretion rate was low. Higher redshifts measurements would distinguish between these possibilities.
2994. Radio and mid-IR counterpart of submm galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/413/2314
Title:
Radio and mid-IR counterpart of submm galaxies
Short Name:
J/MNRAS/413/2314
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present radio and infrared (3.6-24um) counterparts to submillimetre galaxies (SMGs) detected in the Extended Chandra Deep Field-South with the Large APEX Bolometer Camera (LABOCA) 870um bolometer camera on the 12m Atacama Pathfinder Experiment. Using the Very Large Array at .4GHz and Spitzer, we have identified secure counterparts to 79 of the 126 SMGs [signal-to-noise ratio (S/N)>3.7, S870>4.4mJy] in the field, 62 via their radio and/or 24um emission, the remainder using a colour-flux cut on Infrared Array Camera 3.6um and 5.8um sources chosen to maximize the number of secure, coincident radio and 24um counterparts.
2995. Radio and X-ray-emitting broad-line AGNs
ID:
ivo://CDS.VizieR/J/ApJ/688/826
Title:
Radio and X-ray-emitting broad-line AGNs
Short Name:
J/ApJ/688/826
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use a recently released SDSS catalog of X-ray-emitting AGNs in conjunction with the FIRST radio survey to investigate the black hole (BH) fundamental plane relationship between the 1.4GHz radio luminosity (L_r_), 0.1-2.4keV X-ray luminosity (L_X_), and black hole mass (M), namely, logL_r_={xi}_RX_logL_X_+{xi}_RM_logM+constant. For this purpose, we compile a large sample of 725 broad-line AGNs, which consists of 498 radio-loud sources and 227 radio-quiet sources. We confirm that radio-loud objects have a steeper slope ({xi}_RX_) with respect to radio-quiet objects and that the dependence of the BH fundamental plane on the BH mass ({xi}_RM_) is weak.
2996. Radio continuum and gas reservoir in NGC 3998
ID:
ivo://CDS.VizieR/J/A+A/592/A94
Title:
Radio continuum and gas reservoir in NGC 3998
Short Name:
J/A+A/592/A94
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the nearby lenticular galaxy NGC 3998. This galaxy is known to host a low-power radio AGN with a kpc-size one-sided jet and a large, nearly polar HI disc. It is therefore a good system to study to understand the relation between the availability of cold-gas and the triggering of AGNs in galaxies. Our new WSRT data reveal two faint, S-shaped radio lobes extending out to ~10 kpc from the galaxy centre. Remarkably, we find that the inner HI disc warps back towards the stellar mid-plane in a way that mirrors the warping of the radio lobes. We suggest that the polar HI disc was accreted through a minor merger, and that the torques causing it to warp in the inner regions are also responsible for feeding the AGN. The "S" shape of the radio lobes would then be due to the radio jets adapting to the changing angular momentum of the accreted gas. The extended radio jets are likely poorly collimated, which would explain their quick fading and, therefore, their rarity in galaxies similar to NGC 3998. The fuelling of the central super-massive black hole is likely occurring via "discrete events", suggested by the observed variability of the radio core and the extremely high core dominance, which we attribute to the formation and ejection of a new jet resulting from a recent fuelling event.
2997. Radio continuum spectra in Virgo cluster region
ID:
ivo://CDS.VizieR/J/A+A/418/1
Title:
Radio continuum spectra in Virgo cluster region
Short Name:
J/A+A/418/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
New radio continuum observations of galaxies in the Virgo cluster region at 4.85, 8.6, and 10.55GHz are presented. These observations are combined with existing measurements at 1.4 and 0.6GHz. The sample includes 81 galaxies where spectra with more than two frequencies could be derived. Galaxies that show a radio-FIR excess exhibit central activity (HII, LINER,AGN). The four Virgo galaxies with the highest absolute radio excess are found within 2 degrees of the center of the cluster. Galaxies showing flat radio spectra also host active centers. There is no clear trend between the spectral index and the galaxy's distance to the cluster center.
2998. Radio continuum spectra of GPS galaxies
ID:
ivo://CDS.VizieR/J/A+A/469/451
Title:
Radio continuum spectra of GPS galaxies
Short Name:
J/A+A/469/451
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent studies have shown that a remarkable share of quasars classified in the literature as gigahertz-peaked spectrum (GPS) sources and high frequency peakers (HFPs) are actually flaring flat-spectrum sources or blazars. Thus, at least among the quasar-type samples, genuine GPS sources and HFPs seem to be rare. We have studied variability and the shape of the radio continuum spectra of a sample of 96 galaxy-type GPS sources and HFPs in order to find out whether there is a similar contamination in the galaxy-type samples.
2999. Radio continuum survey of M33
ID:
ivo://CDS.VizieR/J/A+A/472/785
Title:
Radio continuum survey of M33
Short Name:
J/A+A/472/785
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the exponential scale length of total radio emission, the spectral index distribution, and the linear radio polarization in the Scd galaxy M33. Observations were carried out using the 3.6cm dual channel and the 6.2cm four-channel receivers of the 100-m Effelsberg telescope along with the L-band VLA D-array at 20cm. High spatial resolution and sensitivity in both total and linearly polarized radio continuum emission from M33 were achieved. We found considerable extended emission, not only from the main arms IS and IN, but also from the weaker arms. The large-scale magnetic field exhibits well-ordered spiral structure with almost the same orientation as that of the optical spiral arms; however, it does not show a clear structural correlation or anti-correlation with the optical arms. There is a north-south asymmetry in polarization that is frequency-dependent. We found that the ring mean spectral index versus radius increases faster beyond R=4kpc. At each wavelength, the exponential scale length is larger inside than outside R=4kpc. From the larger scale lengths at R<4kpc, we conclude that star-forming regions are mainly spread over the region R<4kpc without a dominant nuclear concentration. Furthermore, at R>4kpc, a spatial correlation between cosmic rays and star-forming regions may exist. From the behavior of the mean spectral indices obtained from different pairs of the radio continuum data at 3.6, 6.2, and 20cm, we confirm that a decrease in the thermal fraction causes an increase in the spectral index.
3000. Radio data in Dumbbell galaxies
ID:
ivo://CDS.VizieR/J/A+AS/106/1
Title:
Radio data in Dumbbell galaxies
Short Name:
J/A+AS/106/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)

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