- ID:
- ivo://CDS.VizieR/J/A+A/630/A153
- Title:
- Staked SEDs and templates of LBGs at z~3
- Short Name:
- J/A+A/630/A153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore, from a statistical point of view, the rest-frame far-ultraviolet (FUV) to far-infrared (FIR) emission of a population of Lyman-break galaxies (LBGs) at z~3 that cannot be individually detected from current FIR observations. We performed a stacking analysis over a sample of ~17000 LBGs at redshift 2.5<z<3.5 in the COSMOS field. The sample is binned as a function of UV luminosity (L_FUV_), UV continuum slope (beta_UV_), and stellar mass (M*), and then stacked at optical (BVriz bands), near-infrared (YJHKs bands), IRAC (3.6, 4.5, 5.6 and 8.0um), MIPS (24um), PACS (100 and 160 um), SPIRE (250, 350, and 500um), and AzTEC (1.1mm) observations. We obtained 30 rest-frame FUV-to-FIR spectral energy distributions (SEDs) of LBGs at z~3, and analyzed these with the CIGALE SED-fitting analysis code. We were able to derive fully consistent physical parameters, that is, M*, beta_UV_, L_FUV_, L_IR_, A_FUV_, star formation rate, and the slope of the dust attenuation law; we built a semiempirical library of 30 rest-frame FUV-to-FIR stacked LBG SEDs as functions of L_FUV_, beta_UV_, and M*. Additionally, We used the so-called IR-excess (IRX) to investigate the dust attenuation and the shape of the dust attenuation curve as a function of L_UV_, beta_UV_ and M*.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/468/1009
- Title:
- Star formation in Perseus. II.
- Short Name:
- J/A+A/468/1009
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hatchell et al. (2005, Cat. <J/A+A/440/151>, Paper I) published a submillimetre continuum map of the Perseus molecular cloud, detecting the starless and protostellar cores within it. The aim is to determine the evolutionary stage of each submm core in Perseus, and investigate the lifetimes of these phases.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A15
- Title:
- Star-forming galaxies in AKARI Deep Field-South
- Short Name:
- J/A+A/562/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The main aim of this work is the characterization of physical properties of galaxies detected in the far infrared (FIR) in the AKARI Deep Field-South (ADF-S) survey. Starting from a catalog of the brightest 1000 ADF-S sources in the WIDE-S (90um) AKARI band, we constructed a subsample of galaxies with spectral coverage from the ultraviolet to the far-infrared. Then, we analyzed the multiwavelength properties of this 90um-selected sample of galaxies. For galaxies without known spectroscopic redshifts we computed photometric redshifts using codes Le PHARE and CIGALE, tested these photometric redshifts using spectroscopic redshifts, and compared the performances of both codes. To test the reliability of parameters obtained by fitting Spectral Energy Distributions, a mock catalogue has been generated. We built a large multiwavelength catalog of more than 500 ADF-S galaxies. We successfully fitted Spectral Energy Distributions of 186 galaxies with {chi}^2^<4, and analyzed the output parameters of the fits. We conclude that our sample consists mostly of nearby actively star-forming galaxies, and all our galaxies have a relatively high metallicity. We estimated photometric redshifts for 113 galaxies from the whole ADF-S sample. Comparing the performance of Le PHARE and CIGALE, we found that CIGALE gives more reliable redshift estimates for our galaxies, which implies that including the IR photometry allows for substantial improvement of photometric redshift estimation.
- ID:
- ivo://CDS.VizieR/J/ApJ/692/556
- Title:
- Star forming galaxy templates
- Short Name:
- J/ApJ/692/556
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We show that measures of star formation rates (SFRs) for infrared galaxies using either single-band 24um or extinction-corrected Pa{alpha} luminosities are consistent in the total infrared luminosity =L(IR)~10^10^L_{{sun}}_ range. As a part of this work, we constructed spectral energy distribution templates for eleven luminous and ultraluminous purely star forming infrared galaxies and over the spectral range 0.4um to 30cm. We use these templates and the SINGS data to construct average templates from 5um to 30cm for infrared galaxies with L(IR)=5x10^9^ to 10^13^L_{{sun}}_.
- ID:
- ivo://CDS.VizieR/J/AJ/134/2398
- Title:
- Stellar SEDs in SDSS and 2MASS filters
- Short Name:
- J/AJ/134/2398
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sloan Digital Sky Survey (SDSS) and Two Micron All Sky Survey (2MASS) are rich resources for studying stellar astrophysics and the structure and formation history of the Galaxy. As new surveys and instruments adopt similar filter sets, it is increasingly important to understand the properties of the ugrizJHKs stellar locus, both to inform studies of "normal" main-sequence stars and enable robust searches for point sources with unusual colors. Using a sample of ~600000 point sources detected by SDSS and 2MASS, we tabulate the position and width of the ugrizJHKs stellar locus as a function of g-i color, and provide accurate polynomial fits. We map the Morgan-Keenan spectral type sequence to the median stellar locus by using synthetic photometry of spectral standards and by analyzing 3000 SDSS stellar spectra with a custom spectral typing pipeline, described in the Appendix to this paper. We develop an algorithm to calculate a point source's minimum separation from the stellar locus in a seven-dimensional color space, and use it to robustly identify objects with unusual colors, as well as spurious SDSS/2MASS matches.
- ID:
- ivo://CDS.VizieR/III/208
- Title:
- Sternberg Spectrophotometric Catalog
- Short Name:
- III/208
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains the energy distribution data of 866 stars of different spectral type and luminosity classes in the range 3225-7625{AA} with the step 50{AA}. The observations were made at the Crimean Station of the Sternberg Astronomical Institute during 1970-1984 using spectrophotometer installed at the 48-cm and 60-cm Zeiss reflectors. Standards are Beta Ari, Gamma Ori, Beta Tau, Alfa Leo, Eta UMa, Alfa Lyr, Alfa Aql and Alfa Peg. Energy distribution data in the spectra of standard Stars are based on the calibration of Vega published by Hayes (1985IAUS..111..225H). The average accuracy of the catalogue data is 3.2%. Monochromatic fluxes are in erg/(cm^2^.s.cm*10^-6^). Zero flux is expressed as E-12.
- ID:
- ivo://CDS.VizieR/J/ApJ/853/172
- Title:
- "Super-deblended" dust emission in galaxies. I.
- Short Name:
- J/ApJ/853/172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new technique to measure multi-wavelength "super-deblended" photometry from highly confused images, which we apply to Herschel and ground-based far-infrared (FIR) and (sub-)millimeter (mm) data in the northern field of the Great Observatories Origins Deep Survey (GOODS-N). There are two key novelties. First, starting with a large database of deep Spitzer 24{mu}m and VLA 20cm detections that are used to define prior positions for fitting the FIR/submm data, we perform an active selection of useful priors independently at each frequency band, moving from less to more confused bands. Exploiting knowledge of redshift and all available photometry, we identify hopelessly faint priors that we remove from the fitting pool. This approach significantly reduces blending degeneracies and allows reliable photometry to be obtained for galaxies in FIR+mm bands. Second, we obtain well-behaved, nearly Gaussian flux density uncertainties, individually tailored to all fitted priors for each band. This is done by exploiting extensive simulations that allow us to calibrate the conversion of formal fitting uncertainties to realistic uncertainties, depending on directly measurable quantities. We achieve deeper detection limits with high fidelity measurements and uncertainties at FIR+mm bands. As an illustration of the utility of these measurements, we identify 70 galaxies with z>=3 and reliable FIR+mm detections. We present new constraints on the cosmic star formation rate density at 3<z<6, finding a significant contribution from z>=3 dusty galaxies that are missed by optical-to-near-infrared color selection. Photometric measurements for 3306 priors, including more than 1000 FIR+mm detections, are released publicly with our catalog.
- ID:
- ivo://CDS.VizieR/J/A+A/488/867
- Title:
- Synchrotron peak frequency of 135 AGN
- Short Name:
- J/A+A/488/867
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The blazar sequence is a scenario in which the bolometric luminosity of the blazar governs the appearance of its spectral energy distribution. The most prominent result is the significant negative correlation between the synchrotron peak frequencies and the synchrotron peak luminosities of the blazar population. Observational studies of the blazar sequence have, in general, neglected the effect of Doppler boosting. We study the dependence of both the synchrotron peak frequency and luminosity with Doppler-corrected quantities. We determine the spectral energy distributions of 135 radio-bright AGN and find the best-fit parabolic function for the distribution to quantify their synchrotron emission. The corresponding measurements of synchrotron peak luminosities and frequencies are Doppler-corrected with a new set of Doppler factors calculated from variability data. The relevant correlations for the blazar sequence are determined for these intrinsic quantities.
- ID:
- ivo://CDS.VizieR/J/A+A/570/A29
- Title:
- TBOSS Survey I: Herschel/PACS
- Short Name:
- J/A+A/570/A29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With Herschel PACS 134 low mass members of the Taurus star-forming region spanning the M4-L0 spectral type range and covering the transition from low mass stars to brown dwarfs were observed. Combining the new Herschel results with other programs, a total of 150 of the 154 M4-L0 Taurus members members have observations with Herschel. Among the 150 targets, 70um flux densities were measured for 7 of the 7 Class I objects, 48 of the 67 Class II members, and 3 of the 76 Class III targets. For the detected Class II objects, the median 70um flux density level declines with spectral type, however, the distribution of excess relative to central object flux density does not change across the stellar/substellar boundary in the M4-L0 range. Connecting the 70um TBOSS values with the results from K0-M3 Class II members results in the first comprehensive census of far-IR emission across the full mass spectrum of the stellar and substellar population of a star-forming region, and the median flux density declines with spectral type in a trend analogous to the flux density decline expected for the central objects. Based on an initial exploration of the impact of different physical parameters; inclination, scale height and flaring have the largest influence on the PACS flux densities. From the 24um to 70um spectral index of the SEDs, 5 new candidate transition disks were identified. The steep 24um to 70um slope for a subset of 8 TBOSS targets may be an indication of truncated disks in these systems. Two examples of mixed pair systems that include secondaries with disks were measured. Finally, comparing the TBOSS results with a Herschel study of Ophiuchus brown dwarfs reveals a lower fraction of disks around the Taurus substellar population.
- ID:
- ivo://CDS.VizieR/J/MNRAS/493/2438
- Title:
- The 2BIGB gamma-ray blazars catalog
- Short Name:
- J/MNRAS/493/2438
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the results of a {gamma}-ray likelihood analysis over all the extreme and high synchrotron peak blazars (EHSP and HSP) from the 3HSP catalogue. We investigate 2013 multifrequency positions under the eyes of Fermi Large Area Telescope, considering 11yr of observations in the energy range between 500MeV and 500GeV, which results in 1160 {gamma}-ray signatures detected down to the TS=9 threshold. The detections include 235 additional sources concerning the Fermi Large Area Telescope Fourth Source Catalog (4FGL), all confirmed via high-energy TS (Test Statistic) maps, and represent an improvement of ~25% for the number of EHSP and HSP currently described in {gamma}-rays. We build the {gamma}-ray spectral energy distribution (SED) for all the 1160 2BIGB sources, plot the corresponding {gamma}-ray logN-logS, and measure their total contribution to the extragalactic gamma-ray background, which reaches up to ~33% at 100GeV. Also, we show that the {gamma}-ray detectability improves according to the synchrotron peak flux as represented by the figure of merit parameter, and note that the search for TeV peaked blazars may benefit from considering HSP and EHSP as a whole, instead of EHSPs only. The 2BIGB acronym stands for 'Second Brazil-ICRANet Gamma-ray Blazars' catalogue.
