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- ID:
- ivo://CDS.VizieR/J/MNRAS/432/2182
- Title:
- FIR bright sources of M83
- Short Name:
- J/MNRAS/432/2182
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate star formation and dust heating in the compact far-infrared (FIR) bright sources detected in the Herschel maps of M83. We use the source extraction code GETSOURCES to detect and extract sources in the FIR, as well as their photometry in the mid-infrared and H{alpha}. By performing infrared spectral energy distribution fitting and applying an H{alpha}-based star formation rate (SFR) calibration, we derive the dust masses and temperatures, SFRs, gas masses and star formation efficiencies (SFEs). The detected sources lie exclusively on the spiral arms and represent giant molecular associations, with gas masses and sizes of 106-108M{sun} and 200-300pc, respectively. The inferred parameters show little to no radial dependence and there is only a weak correlation between the SFRs and gas masses, which suggests that more massive clouds are less efficient at forming stars. Dust heating is mainly due to local star formation. However, although the sources are not optically thick, the total intrinsic young stellar population luminosity can almost completely account for the dust luminosity. This suggests that other radiation sources also contribute to the dust heating and approximately compensate for the unabsorbed fraction of UV light.
- ID:
- ivo://CDS.VizieR/J/ApJ/840/21
- Title:
- FIR data of IR-bright dust-obscured galaxies (DOGs)
- Short Name:
- J/ApJ/840/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the star-forming activity of a sample of infrared (IR)-bright dust-obscured galaxies (DOGs) that show an extreme red color in the optical and IR regime, (i-[22])_AB_>7.0. Combining an IR-bright DOG sample with the flux at 22{mu}m>3.8mJy discovered by Toba & Nagao (2016ApJ...820...46T) with the IRAS faint source catalog version 2 and AKARI far-IR (FIR) all-sky survey bright source catalog version 2, we selected 109 DOGs with FIR data. For a subsample of seven IR-bright DOGs with spectroscopic redshifts (0.07<z<1.0) that were obtained from the literature, we estimated their IR luminosity, star formation rate (SFR), and stellar mass based on the spectral energy distribution fitting. We found that (1) the WISE 22{mu}m luminosity at the observed frame is a good indicator of IR luminosity for IR-bright DOGs and (2) the contribution of the active galactic nucleus to IR luminosity increases with IR luminosity. By comparing the stellar mass and SFR relation for our DOG sample and the literature, we found that most of the IR-bright DOGs lie significantly above the main sequence of star-forming galaxies at similar redshift, indicating that the majority of IRAS- or AKARI-detected IR-bright DOGs are starburst galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/682/985
- Title:
- FIREWORKS photometry of GOODS CDF-S
- Short Name:
- J/ApJ/682/985
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a Ks-selected catalog, dubbed FIREWORKS, for the Chandra Deep Field-South (CDF-S) containing photometry in the U_38_, B_435_, B, V, V_606_, R, i_775_, I, z_850_, J, H, Ks, [3.6um], [4.5um], [5.8um], [8.0um], and MIPS [24um] bands. The imaging has a typical K^tot^_s,AB_ limit of 24.3mag (5{sigma}) and coverage over 113arcmin^2^ in all bands and 138arcmin^2^ in all bands but H. We cross-correlate our catalog with the 1Ms X-ray catalog by Giacconi et al. (2002, Cat. J/ApJS/139/369) and with all available spectroscopic redshifts to date. We find and explain systematic differences in a comparison with the "z_850_+Ks"-selected GOODS-MUSIC catalog (Cat. J/A+A/449/951) that covers ~90% of the field. We exploit the U_38_-to-24um photometry to determine which Ks-selected galaxies at 1.5<z<2.5 have the brightest total IR luminosities and which galaxies contribute most to the integrated total IR emission. The answer to both questions is that red galaxies are dominating in the IR. This is true no matter whether color is defined in the rest-frame UV, optical, or optical-near-IR. We do find, however, that among the reddest galaxies in the rest-frame optical, there is a population of sources with only little mid-IR emission, suggesting a quiescent nature.
- ID:
- ivo://CDS.VizieR/J/ApJ/849/63
- Title:
- FIR-mm data of YSOs in star-forming regions
- Short Name:
- J/ApJ/849/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Far-infrared and (sub)millimeter fluxes can be used to study dust in protoplanetary disks, the building blocks of planets. Here, we combine observations from the Herschel Space Observatory with ancillary data of 284 protoplanetary disks in the Taurus, Chamaeleon I, and Ophiuchus star-forming regions, covering from the optical to mm/cm wavelengths. We analyze their spectral indices as a function of wavelength and determine their (sub)millimeter slopes when possible. Most disks display observational evidence of grain growth, in agreement with previous studies. No correlation is found between other tracers of disk evolution and the millimeter spectral indices. A simple disk model is used to fit these sources, and we derive posterior distributions for the optical depth at 1.3mm and 10au, the disk temperature at this same radius, and the dust opacity spectral index {beta}. We find the fluxes at 70{mu}m to correlate strongly with disk temperatures at 10au, as derived from these simple models. We find tentative evidence for spectral indices in Chamaeleon I being steeper than those of disks in Taurus/Ophiuchus, although more millimeter observations are needed to confirm this trend and identify its possible origin. Additionally, we determine the median spectral energy distribution of each region and find them to be similar across the entire wavelength range studied, possibly due to the large scatter in disk properties and morphologies.
- ID:
- ivo://CDS.VizieR/J/A+A/575/A80
- Title:
- FIR photometry of 3CR galaxies
- Short Name:
- J/A+A/575/A80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Herschel (PACS and SPIRE) far-infrared (FIR) photometry of a complete sample of z>1 3CR sources, from the Herschel guaranteed time project The Herschel Legacy of distant radio-loud AGN. Combining these with existing Spitzer photometric data, we perform an infrared (IR) spectral energy distribution (SED) analysis of these landmark objects in extragalactic research to study the star formation in the hosts of some of the brightest active galactic nuclei (AGN) known at any epoch. Accounting for the contribution from an AGN-powered warm dust component to the IR SED, about 40% of our objects undergo episodes of prodigious, ULIRG-strength star formation, with rates of hundreds of solar masses per year, coeval with the growth of the central supermassive black hole. Median SEDs imply that the quasar and radio galaxy hosts have similar FIR properties, in agreement with the orientation-based unification for radio-loud AGN. The star-forming properties of the AGN hosts are similar to those of the general population of equally massive non-AGN galaxies at comparable redshifts, thus there is no strong evidence of universal quenching of star formation (negative feedback) within this sample. Massive galaxies at high redshift may be forming stars prodigiously, regardless of whether their supermassive black holes are accreting or not.
- ID:
- ivo://CDS.VizieR/J/ApJ/768/13
- Title:
- FIR properties of SDSS type 1 quasars
- Short Name:
- J/ApJ/768/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Spitzer Space Telescope Enhanced Imaging Products and the Spitzer Archival Far-InfraRed Extragalactic Survey to study the spectral energy distributions (SEDs) of spectroscopically confirmed type 1 quasars selected from the Sloan Digital Sky Survey (SDSS). By combining the Spitzer and SDSS data with the Two Micron All Sky Survey, we are able to construct a statistically robust rest-frame 0.1-100{mu}m type 1 quasar template. We find that the quasar population is well-described by a single power-law SED at wavelengths less than 20{mu}m, in good agreement with previous work. However, at longer wavelengths, we find a significant excess in infrared luminosity above an extrapolated power-law, along with significant object-to-object dispersion in the SED. The mean excess reaches a maximum of 0.8dex at rest-frame wavelengths near 100{mu}m.
- ID:
- ivo://CDS.VizieR/J/ApJ/811/58
- Title:
- FIR properties of SDSS 0.1<z<5 quasars
- Short Name:
- J/ApJ/811/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the public data from the Herschel wide-field surveys, we study the far-infrared properties of optical-selected quasars from the Sloan Digital Sky Survey. Within the common area of ~172deg^2^, we have identified the far-infrared counterparts for 354 quasars, among which 134 are highly secure detections in the Herschel 250um band (signal-to-noise ratios >=5). This sample is the largest far-infrared quasar sample of its kind, and spans a wide redshift range of 0.14<=z<=4.7. Their far-infrared spectral energy distributions, which are due to the cold-dust components within the host galaxies, are consistent with being heated by active star formation. In most cases (>~80%), their total infrared luminosities as inferred from only their far-infrared emissions (L_IR_^(cd)^) already exceed 10^12^L_{sun}_, and thus these objects qualify as ultra-luminous infrared galaxies. There is no correlation between L_IR_^(cd)^ and the absolute magnitudes, the black hole masses or the X-ray luminosities of the quasars, which further support that their far-infrared emissions are not due to their active galactic nuclei. A large fraction of these objects (>~50%-60%) have star-formation rates >~300M_{sun}_/yr. Such extreme starbursts among optical quasars, however, is only a few percent. This fraction varies with redshift, and peaks at around z~2. Among the entire sample, 136 objects have secure estimates of their cold-dust temperatures (T), and we find that there is a dramatic increasing trend of T with increasing L_IR_^(cd)^. We interpret this trend as the envelope of the general distribution of infrared galaxies on the (T, L_IR_^(cd)^) plane.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/19
- Title:
- FIR spectra of AGNs from Herschel
- Short Name:
- J/ApJS/226/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/Photoconductor Array Camera and Spectrometer (PACS) archive for a sample of 170 local active galactic nuclei (AGNs), plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published Spitzer/IRS and Herschel/SPIRE line fluxes are included to extend our database to the full 10-600{mu}m spectral range. The observations are compared to a set of Cloudy photoionization models to estimate the above physical quantities through different diagnostic diagrams. We confirm the presence of a stratification of gas density in the emission regions of the galaxies, which increases with the ionization potential of the emission lines. The new [OIV]_25.9um_/[OIII]_88um_ versus [NeIII]_15.6um_/[NeII]_12.8um_ diagram is proposed as the best diagnostic to separate (1) AGN activity from any kind of star formation and (2) low-metallicity dwarf galaxies from starburst galaxies. Current stellar atmosphere models fail to reproduce the observed [OIV]_25.9um_/[OIII]_88um_ ratios, which are much higher when compared to the predicted values. Finally, the ([NeIII]_15.6um_+[NeII]_12.8um_)/([SIV]_10.5um_+[SIII]_18.7um_) ratio is proposed as a promising metallicity tracer to be used in obscured objects, where optical lines fail to accurately measure the metallicity. The diagnostic power of mid- to far-infrared spectroscopy shown here for local galaxies will be of crucial importance to study galaxy evolution during the dust-obscured phase at the peak of the star formation and black hole accretion activity (1<z<4). This study will be addressed by future deep spectroscopic surveys with present and forthcoming facilities such as the James Webb Space Telescope, the Atacama Large Millimeter/submillimeter Array, and the Space Infrared telescope for Cosmology and Astrophysics.
- ID:
- ivo://CDS.VizieR/J/A+A/506/1563
- Title:
- First AGILE catalog of gamma-ray sources
- Short Name:
- J/A+A/506/1563
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first catalog of high-confidence {gamma}-ray sources detected by the AGILE satellite during observations performed from July 9, 2007 to June 30, 2008. Cataloged sources were detected by merging all the available data over the entire time period. AGILE, launched in April 2007, is an ASI mission devoted to {gamma}-ray observations in the 30MeV-50GeV energy range, with simultaneous X-ray imaging capability in the 18-60keV band. This catalog is based on Gamma-Ray Imaging Detector (GRID) data for energies greater than 100MeV. For the first AGILE catalog, we adopted a conservative analysis, with a high-quality event filter optimized to select {gamma}-ray events within the central zone of the instrument field of view (radius of 40{deg}). This is a significance-limited (4{sigma}) catalog, and it is not a complete flux-limited sample due to the non-uniform first-year AGILE sky coverage. The catalog includes 47 sources, 21 of which are associated with confirmed or candidate pulsars, 13 with blazars (7 FSRQ, 4 BL Lacs, 2 unknown type), 2 with HMXRBs, 2 with SNRs, 1 with a colliding-wind binary system, and 8 with unidentified sources.