- ID:
- ivo://CDS.VizieR/J/A+A/622/A132
- Title:
- Dust emission profiles of DustPedia galaxies
- Short Name:
- J/A+A/622/A132
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Most radiative transfer models assume that dust in spiral galaxies is distributed exponentially. In this paper our goal is to verify this assumption by analysing the two-dimensional large-scale distribution of dust in galaxies from the DustPedia sample. For this purpose, we have made use of Herschel imaging in five bands, from 100 to 500um, in which the cold dust constituent is primarily traced and makes up the bulk of the dust mass in spiral galaxies. For a subsample of 320 disc galaxies, we successfully performed a simultaneous fitting with a single Sersic model of the Herschel images in all five bands using the multi-band modelling code GALFITM. We report that the Sersic index n, which characterises the shape of the Sersic profile, lies systematically below 1 in all Herschel bands and is almost constant with wavelength. The average value at 250um is 0.67+/-0.37 (187 galaxies are fitted with n^250^<=0.75, 87 galaxies have 0.75<n^250^<=1.25, and 46 - with n^250^>1.25). Most observed profiles exhibit a depletion in the inner region (at r<0.3-0.4 of the optical radius r25) and are more or less exponential in the outer part. We also find breaks in the dust emission profiles at longer distances (0.5-0.6)r25 which are associated with the breaks in the optical and near-infrared. We assumed that the observed deficit of dust emission in the inner galaxy region is related to the depression in the radial profile of the HI surface density in the same region because the atomic gas reaches high enough surface densities there to be transformed into molecular gas. If a galaxy has a triggered star formation in the inner region (for example, because of a strong bar instability, which transfers the gas inwards to the centre, or a pseudobulge formation), no depletion or even an excess of dust emission in the centre is observed.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/800/51
- Title:
- DUSTiNGS II. Metal-poor dusty AGB stars
- Short Name:
- J/ApJ/800/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The DUSTiNGS survey (DUST in Nearby Galaxies with Spitzer) is a 3.6 and 4.5{mu}m imaging survey of 50 nearby dwarf galaxies designed to identify dust-producing asymptotic giant branch (AGB) stars and massive stars. Using two epochs, spaced approximately six months apart, we identify a total of 526 dusty variable AGB stars (sometimes called "extreme" or x-AGB stars; [3.6]-[4.5]>0.1mag). Of these, 111 are in galaxies with [Fe/H]<-1.5 and 12 are in galaxies with [Fe/H]<-2.0, making them the most metal-poor dust-producing AGB stars known. We compare these identifications to those in the literature and find that most are newly discovered large-amplitude variables, with the exception of {approx}30 stars in NGC185 and NGC147, 1 star in IC1613, and 1 star in Phoenix. The chemical abundances of the x-AGB variables are unknown, but the low metallicities suggest that they are more likely to be carbon-rich than oxygen-rich and comparisons with existing optical and near-IR photometry confirm that 70 of the x-AGB variables are confirmed or likely carbon stars. We see an increase in the pulsation amplitude with increased dust production, supporting previous studies suggesting that dust production and pulsation are linked. We find no strong evidence linking dust production with metallicity, indicating that dust can form in very metal-poor environments.
- ID:
- ivo://CDS.VizieR/J/ApJS/216/10
- Title:
- DUSTiNGS. I. The Good Source Catalog
- Short Name:
- J/ApJS/216/10
- Date:
- 22 Oct 2021
- Publisher:
- CDS
- Description:
- Nearby resolved dwarf galaxies provide excellent opportunities for studying the dust-producing late stages of stellar evolution over a wide range of metallicity (-2.7<~[Fe/H]<~-1.0). Here, we describe DUSTiNGS (DUST in Nearby Galaxies with Spitzer): a 3.6 and 4.5{mu}m post-cryogen Spitzer Space Telescope imaging survey of 50 dwarf galaxies within 1.5Mpc that is designed to identify dust-producing asymptotic giant branch (AGB) stars and massive stars. The survey includes 37 dwarf spheroidal, 8 dwarf irregular, and 5 transition-type galaxies. This near-complete sample allows for the building of statistics on these rare phases of stellar evolution over the full metallicity range. The photometry is >75% complete at the tip of the red giant branch for all targeted galaxies, with the exception of the crowded inner regions of IC 10, NGC 185, and NGC 147. This photometric depth ensures that the majority of the dust-producing stars, including the thermally pulsing AGB stars, are detected in each galaxy. The images map each galaxy to at least twice the half-light radius to ensure that the entire evolved star population is included and to facilitate the statistical subtraction of background and foreground contamination, which is severe at these wavelengths. In this overview, we describe the survey, the data products, and preliminary results. We show evidence for the presence of dust-producing AGB stars in eight of the targeted galaxies, with metallicities as low as [Fe/H]=-1.9, suggesting that dust production occurs even at low metallicity.
- ID:
- ivo://CDS.VizieR/J/ApJ/851/152
- Title:
- DUSTiNGS. IV. AGB spectral types with HST
- Short Name:
- J/ApJ/851/152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The survey for DUST in Nearby Galaxies with Spitzer (DUSTiNGS) identified several candidate Asymptotic Giant Branch (AGB) stars in nearby dwarf galaxies and showed that dust can form even in very metal-poor systems (Z~0.008Z_{sun}_). Here, we present a follow-up survey with WFC3/IR on the Hubble Space Telescope (HST), using filters that are capable of distinguishing carbon-rich (C-type) stars from oxygen-rich (M-type) stars: F127M, F139M, and F153M. We include six star-forming DUSTiNGS galaxies (NGC147, IC10, Pegasus dIrr, SextansB, SextansA, and Sag DIG), all more metal-poor than the Magellanic Clouds and spanning 1dex in metallicity. We double the number of dusty AGB stars known in these galaxies and find that most are carbon rich. We also find 26 dusty M-type stars, mostly in IC 10. Given the large dust excess and tight spatial distribution of these M-type stars, they are most likely on the upper end of the AGB mass range (stars undergoing Hot Bottom Burning). Theoretical models do not predict significant dust production in metal-poor M-type stars, but we see evidence for dust excess around M-type stars even in the most metal-poor galaxies in our sample (12+log(O/H)=7.26-7.50). The low metallicities and inferred high stellar masses (up to ~10M_{sun}_) suggest that AGB stars can produce dust very early in the evolution of galaxies (~30Myr after they form), and may contribute significantly to the dust reservoirs seen in high-redshift galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/877/49
- Title:
- DUSTiNGS. V. 3.6 and 4.5um light curves
- Short Name:
- J/ApJ/877/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The survey for DUST in Nearby Galaxies with Spitzer (DUSTiNGS) has identified hundreds of candidate dust-producing asymptotic giant branch (AGB) stars in several nearby metal-poor galaxies. We have obtained multi-epoch follow-up observations for these candidates with the Spitzer Space Telescope and measured their infrared (IR) light curves. This has allowed us to confirm their AGB nature and investigate pulsation behavior at very low metallicity. We have obtained high-confidence pulsation periods for 88 sources in seven galaxies. We have confirmed DUSTiNGS variable star candidates with a 20% success rate and determined the pulsation properties of 19 sources already identified as thermally pulsing AGB stars. We find that the AGB pulsation properties are similar in all galaxies surveyed here, with no discernible difference between the DUSTiNGS galaxies (down to 1.4% solar metallicity; [Fe/H]=-1.85) and the far more metal-rich Magellanic Clouds (up to 50% solar metallicity; [Fe/H]=-0.38). These results strengthen the link between dust production and pulsation in AGB stars and establish the IR period-luminosity relation as a reliable tool (+/-4%) for determining distances to galaxies, regardless of metallicity.
1706. Dust in Sb and Sc K-band
- ID:
- ivo://CDS.VizieR/J/A+AS/108/621
- Title:
- Dust in Sb and Sc K-band
- Short Name:
- J/A+AS/108/621
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJ/744/150
- Title:
- Dust-obscured galaxies (DOGs) at z=~2
- Short Name:
- J/ApJ/744/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer Space Telescope has identified a population of ultraluminous infrared galaxies (ULIRGs) at z~2 that may play an important role in the evolution of massive galaxies. We measure the stellar masses (M_*_) of two populations of Spitzer-selected ULIRGs that have extremely red R-[24] colors (dust-obscured galaxies, or DOGs) and compare our results with submillimeter-selected galaxies (SMGs). One set of 39 DOGs has a local maximum in their mid-infrared (mid-IR) spectral energy distribution (SED) at rest frame 1.6um associated with stellar emission ("bump DOGs"), while the other set of 51 DOGs have power-law mid-IR SEDs that are typical of obscured active galactic nuclei ("power-law DOGs"). We measure M_*_ by applying Charlot & Bruzual (1991ApJ...367..126C) stellar population synthesis models to broadband photometry in the rest-frame ultraviolet, optical, and near-infrared of each of these populations.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/116
- Title:
- Dust-obscured galaxies in the local universe
- Short Name:
- J/ApJ/769/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use Wide-field Infrared Survey Explorer (WISE), AKARI, and Galaxy Evolution Explorer (GALEX) data to select local analogs of high-redshift (z~2) dust obscured galaxies (DOGs). We identify 47 local DOGs with S_12{mu}m_/S_0.22{mu}m_>=892 and S_12{mu}m_>20mJy at 0.05<z<0.08 in the Sloan Digital Sky Survey data release 7. The infrared (IR) luminosities of these DOGs are in the range 3.4x10^10^(L_{sun}_)<~L_IR_<~7.0x10^11^(L_{sun}_) with a median L_IR_ of 2.1x10^11^(L_{sun}_). We compare the physical properties of local DOGs with a control sample of galaxies that have lower S_12{mu}m_/S_0.22{mu}m_ but have similar redshift, IR luminosity, and stellar mass distributions. Both WISE 12{mu}m and GALEX near-ultraviolet (NUV) flux densities of DOGs differ from the control sample of galaxies, but the difference is much larger in the NUV. Among the 47 DOGs, 36%+/-7% have small axis ratios in the optical (i.e., b/a<0.6), larger than the fraction among the control sample (17%+/-3%). There is no obvious sign of interaction for many local DOGs. No local DOGs have companions with comparable optical magnitudes closer than ~50kpc. The large- and small-scale environments of DOGs are similar to the control sample. Many physical properties of local DOGs are similar to those of high-z DOGs, even though the IR luminosities of local objects are an order of magnitude lower than for the high-z objects: the presence of two classes (active galactic nuclei- and star formation-dominated) of DOGs, abnormal faintness in the UV rather than extreme brightness in the mid-IR, and diverse optical morphology. These results suggest a common underlying physical origin of local and high-z DOGs. Both seem to represent the high-end tail of the dust obscuration distribution resulting from various physical mechanisms rather than a unique phase of galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/582/A121
- Title:
- Dust properties in galaxies
- Short Name:
- J/A+A/582/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we aim to provide a consistent analysis of the dust properties from metal-poor to metal-rich environments by linking them to fundamental galactic parameters. We consider two samples of galaxies: the Dwarf Galaxy Survey (DGS) and the Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel (KINGFISH), totalling 109 galaxies, spanning almost 2dex in metallicity. We collect infrared (IR) to submillimetre (submm) data for both samples and present the complete data set for the DGS sample. We model the observed spectral energy distributions (SED) with a physically-motivated dust model to access the dust properties: dust mass, total-IR luminosity, polycyclic aromatic hydrocarbon (PAH) mass fraction, dust temperature distribution, and dust-to-stellar mass ratio. Using a different SED model (modified black body), different dust composition (amorphous carbon in lieu of graphite), or a different wavelength coverage at submm wavelengths results in differences in the dust mass estimate of a factor two to three, showing that this parameter is subject to non-negligible systematic modelling uncertainties. We find half as much dust with the amorphous carbon dust composition. For eight galaxies in our sample, we find a rather small excess at 500{mu}m (<=1.5{sigma}). We find that the dust SED of low-metallicity galaxies is broader and peaks at shorter wavelengths compared to more metal-rich systems, a sign of a clumpier medium in dwarf galaxies. The PAH mass fraction and dust temperature distribution are found to be driven mostly by the specific star formation rate, sSFR, with secondary effects from metallicity. The correlations between metallicity and dust mass or total-IR luminosity are direct consequences of the stellar mass-metallicity relation. The dust-to-stellar mass ratios of metal-rich sources follow the well-studied trend of decreasing ratio for decreasing sSFR. The relation is more complex for low-metallicity galaxies with high sSFR, and depends on the chemical evolutionary stage of the source (i.e. gas-to-dust mass ratio). Dust growth processes in the ISM play a key role in the dust mass build-up with respect to the stellar content at high sSFR and low metallicity. We conclude that the evolution of the dust properties from metal-poor to metal-rich galaxies derives from a complex interplay between star formation activity, stellar mass, and metallicity.
- ID:
- ivo://CDS.VizieR/J/A+A/565/A128
- Title:
- Dust SED in HRS nearby galaxies
- Short Name:
- J/A+A/565/A128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Although it accounts only for a small fraction of the baryonic mass, dust has a profound impact on the physical processes at play in galaxies. Thus, to understand the evolution of galaxies, it is essential not only to characterize dust properties per se, but also in relation to global galaxy properties. To do so, we derive the dust properties of galaxies in a volume limited, K-band selected sample, the Herschel Reference Survey (HRS). We gather infrared photometric data from 8{mu}m to 500{mu}m from Spitzer, WISE, IRAS, and Herschel for all of the HRS galaxies. Draine & Li (2007ApJ...663..866D) models are fit to the data from which the stellar contribution has been carefully removed. We find that our photometric coverage is sufficient to constrain all of the parameters of the Draine & Li models and that a strong constraint on the 20-60{mu}m range is mandatory to estimate the relative contribution of the photo-dissociation regions to the infrared spectral energy distribution (SED). The SED models tend to systematically underestimate the observed 500{mu}m flux densities, especially for low-mass systems. We provide the output parameters for all of the galaxies, i.e., the minimum intensity of the interstellar radiation field, the fraction of polycyclic aromatic hydrocarbon (PAH), the relative contribution of PDR and evolved stellar population to the dust heating, the dust mass, and the infrared luminosity. For a subsample of gas-rich galaxies, we analyze the relations between these parameters and the main integrated properties of galaxies, such as stellar mass, star formation rate, infrared luminosity, metallicity, H{alpha} and H-band surface brightness, and the far-ultraviolet attenuation. A good correlation between the fraction of PAH and the metallicity is found, implying a weakening of the PAH emission in galaxies with low metallicities and, thus, low stellar masses. The intensity of the diffuse interstellar radiation field and the H-band and H{alpha} surface brightnesses are correlated, suggesting that the diffuse dust component is heated by both the young stars in star-forming regions and the diffuse evolved population. We use these results to provide a new set of infrared templates calibrated with Herschel observations on nearby galaxies and a mean SED template to provide the z=0 reference for cosmological studies. For the same purpose, we place our sample on the SFR-M_*_ diagram. The templates are compared to the most popular infrared SED libraries, enlightening a large discrepancy between all of them in the 20-100{mu}m range.
