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- ID:
- ivo://CDS.VizieR/J/MNRAS/417/2239
- Title:
- SPIRE (f250um>17.4mJy) GOODS-N galaxies
- Short Name:
- J/MNRAS/417/2239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the first time, we investigate the X-ray/infrared (IR) correlation for star-forming galaxies (SFGs) at z~1, using SPIRE submm data from the recently launched Herschel Space Observatory and deep X-ray data from the 2-Ms Chandra Deep Field-North survey. We examine the X-ray/IR correlation in the soft X-ray (SX; 0.5-2keV) and hard X-ray (HX; 2-10keV) bands by comparing our z~1 SPIRE-detected SFGs to equivalently IR-luminous (L_IR_>10^10^L_{sun}_) samples in the local/low-redshift Universe.
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/3335
- Title:
- SPIRE observations of Herschel-BAT sample
- Short Name:
- J/MNRAS/456/3335
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present far-infrared (FIR) and submillimetre photometry from the Herschel Space Observatory's Spectral and Photometric Imaging Receiver (SPIRE) for 313 nearby (z<0.05) active galactic nuclei (AGN). We selected AGN from the 58 month Swift Burst Alert Telescope (BAT) catalogue, the result of an all-sky survey in the 14-195keV energy band, allowing for a reduction in AGN selection effects due to obscuration and host galaxy contamination. We find 46 per cent (143/313) of our sample is detected at all three wavebands and combined with our Photoconductor Array Camera and Spectrometer (PACS) observations represents the most complete FIR spectral energy distributions of local, moderate-luminosity AGN. We find no correlation among the 250, 350, and 500{mu}m luminosities with 14-195keV luminosity, indicating the bulk of the FIR emission is not related to the AGN. However, Seyfert 1s do show a very weak correlation with X-ray luminosity compared to Seyfert 2s and we discuss possible explanations. We compare the SPIRE colours (F_250_/F_350_ and F_350_/F_500_) to a sample of normal star-forming galaxies, finding the two samples are statistically similar, especially after matching in stellar mass. But a colour-colour plot reveals a fraction of the Herschel-BAT AGN are displaced from the normal star-forming galaxies due to excess 500{mu}m emission (E_500_). Our analysis shows E_500_ is strongly correlated with the 14-195keV luminosity and 3.4/4.6{mu}m flux ratio, evidence the excess is related to the AGN. We speculate these sources are experiencing millimetre excess emission originating in the corona of the accretion disc.
- ID:
- ivo://CDS.VizieR/J/AJ/131/250
- Title:
- Spitzer 70 and 160um observations in xFLS
- Short Name:
- J/AJ/131/250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 70 and 160{mu}m observations from the Spitzer extragalactic First Look Survey (xFLS). The data reduction techniques and the methods for producing co-added mosaics and source catalogs are discussed. Currently, 26% of the 70{mu}m sample and 49% of the 160{mu}m-selected sources have redshifts. The majority of sources with redshifts are star-forming galaxies at z<0.5, while about 5% have infrared colors consistent with active galactic nuclei. The observed infrared colors agree with the spectral energy distributions (SEDs) of local galaxies previously determined from IRAS and Infrared Space Observatory data.
- ID:
- ivo://CDS.VizieR/J/ApJS/218/33
- Title:
- Spitzer-CANDELS catalog within 5 deep fields
- Short Name:
- J/ApJS/218/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer-Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (S-CANDELS; PI G.Fazio) is a Cycle 8 Exploration Program designed to detect galaxies at very high redshifts (z>5). To mitigate the effects of cosmic variance and also to take advantage of deep coextensive coverage in multiple bands by the Hubble Space Telescope (HST) Multi-cycle Treasury Program CANDELS, S-CANDELS was carried out within five widely separated extragalactic fields: the UKIDSS Ultra-deep Survey, the Extended Chandra Deep Field South, COSMOS, the HST Deep Field North, and the Extended Groth Strip. S-CANDELS builds upon the existing coverage of these fields from the Spitzer Extended Deep Survey (SEDS), a Cycle 6 Exploration Program, by increasing the integration time from SEDS' 12hr to a total of 50hr but within a smaller area, 0.16deg^2^. The additional depth significantly increases the survey completeness at faint magnitudes. This paper describes the S-CANDELS survey design, processing, and publicly available data products. We present Infrared Array Camera (IRAC) dual-band 3.6+4.5{mu}m catalogs reaching to a depth of 26.5 AB mag. Deep IRAC counts for the roughly 135000 galaxies detected by S-CANDELS are consistent with models based on known galaxy populations. The increase in depth beyond earlier Spitzer/IRAC surveys does not reveal a significant additional contribution from discrete sources to the diffuse Cosmic Infrared Background (CIB). Thus it remains true that only roughly half of the estimated CIB flux from COBE/DIRBE is resolved.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/30
- Title:
- Spitzer catalog of Herschel star-forming galaxies
- Short Name:
- J/ApJS/244/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The largest Herschel extragalactic surveys, H-ATLAS and HerMES, have selected a sample of "ultrared" dusty star-forming galaxies (DSFGs) with rising SPIRE flux densities (S_500_>S_350_>S_250_; the so-called "500{mu}m risers") as an efficient way for identifying DSFGs at higher redshift (z>4). In this paper, we present a large Spitzer follow-up program of 300 Herschel ultrared DSFGs. We have obtained high-resolution Atacama Large Millimeter/submillimeter Array, Northern Extended Millimeter Array, and SMA data for 63 of them, which allow us to securely identify the Spitzer/IRAC counterparts and classify them as gravitationally lensed or unlensed. Within the 63 ultrared sources with high-resolution data, ~65% appear to be unlensed and ~27% are resolved into multiple components. We focus on analyzing the unlensed sample by directly performing multiwavelength spectral energy distribution modeling to derive their physical properties and compare with the more numerous z~2 DSFG population. The ultrared sample has a median redshift of 3.3, stellar mass of 3.7x10^11^M_{sun}_, star formation rate (SFR) of 730M_{sun}_/yr, total dust luminosity of 9.0x10^12^L_{sun}_, dust mass of 2.8x10^9^M_{sun}_, and V-band extinction of 4.0, which are all higher than those of the ALESS DSFGs. Based on the space density, SFR density, and stellar mass density estimates, we conclude that our ultrared sample cannot account for the majority of the star-forming progenitors of the massive, quiescent galaxies found in infrared surveys. Our sample contains the rarer, intrinsically most dusty, luminous, and massive galaxies in the early universe that will help us understand the physical drivers of extreme star formation.
- ID:
- ivo://CDS.VizieR/J/ApJS/184/230
- Title:
- Spitzer high-resolution MIR spectral atlas
- Short Name:
- J/ApJS/184/230
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of Spitzer/IRS high-resolution (R~600) 10-37um spectra for 24 well known starburst galaxies. The spectra are dominated by fine-structure lines, molecular hydrogen lines, and emission bands of polycyclic aromatic hydrocarbons (PAHs). Six out of the eight objects with a known active galactic nucleus (AGN) component show emission of the high excitation [NeV] line. This line is also seen in one other object (NGC 4194) with, a priori, no known AGN component. In addition to strong PAH emission features in this wavelength range (11.3, 12.7, 16.4um), the spectra reveal other weak hydrocarbon features at 10.6, 13.5, 14.2um, and a previously unreported emission feature at 10.75um. An unidentified absorption feature at 13.7um is detected in many of the starbursts. We use the fine-structure lines to derive the abundance of neon and sulfur for 14 objects where the HI 7-6 line is detected. We further use the molecular hydrogen lines to sample the properties of the warm molecular gas. Several basic diagrams characterizing the properties of the sample are also shown. We have combined the spectra of all the pure starburst objects to create a high signal-to-noise ratio template, which is available to the community.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/80
- Title:
- Spitzer/IRAC observations of five deep fields
- Short Name:
- J/ApJ/769/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46deg^2^ to a depth of 26 AB mag (3{sigma}) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5{mu}m. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z=2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6+/-1.0 and 4.4+/-0.8nW/m2/sr at 3.6 and 4.5{mu}m to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.
- ID:
- ivo://CDS.VizieR/J/ApJS/193/13
- Title:
- Spitzer/IRAC sources in the EGS I. SEDs
- Short Name:
- J/ApJS/193/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an IRAC 3.6+4.5um selected catalog in the Extended Groth Strip (EGS) containing photometry from the ultraviolet to the far-infrared and stellar parameters derived from the analysis of the multi-wavelength data. In this paper, we describe the method used to build coherent spectral energy distributions (SEDs) for all the sources. In a forthcoming companion paper, we analyze those SEDs to obtain robust estimations of stellar parameters such as photometric redshifts, stellar masses, and star formation rates. The catalog comprises 76936 sources with [3.6]<=23.75mag (85% completeness level of the IRAC survey in the EGS) over 0.48deg^2^. For approximately 16% of this sample, we are able to deconvolve the IRAC data to obtain robust fluxes for the multiple counterparts found in ground-based optical images. Typically, the SEDs of the IRAC sources in our catalog count with more than 15 photometric data points, spanning from the ultraviolet wavelengths probed by GALEX to the far-infrared observed by Spitzer, and going through ground- and space-based optical and near-infrared data taken with 2-8m class telescopes. Approximately 95% and 90% of all IRAC sources are detected in the deepest optical and near-infrared bands. These fractions are reduced to 85% and 70% for S/N>5 detections in each band. Only 10% of the sources in the catalog have optical spectroscopy and redshift estimations. Almost 20% and 2% of the sources are detected by MIPS at 24 and 70um, respectively. We also cross-correlate our catalog with public X-ray and radio catalogs.
- ID:
- ivo://CDS.VizieR/J/A+A/626/A92
- Title:
- Spitzer/IRS analysis of the 30-micron sources
- Short Name:
- J/A+A/626/A92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis and comparison of the 30{mu}m dust features seen in the Spitzer Space Telescope spectra of 207 carbon-rich asymptotic giant branch (AGB) stars, post-AGB objects, and planetary nebulae (PNe) located in the Milky Way, the Magellanic Clouds (MCs), or the Sagittarius dwarf spheroidal galaxy (Sgr dSph), which are characterised by different average metallicities. We investigated whether the formation of the 30{mu}m feature carrier may be a function of the metallicity. Through this study we expect to better understand the late stages of stellar evolution of carbon-rich stars in these galaxies. Our analysis uses the "Manchester method" as a basis for estimating the temperature of dust for the carbon-rich AGB stars and the PNe in our sample. For post-AGB objects we changed the wavelength ranges used for temperature estimation, because of the presence of the 21{mu}m feature on the short wavelength edge of the 30{mu}m feature. We used a black-body function with a single temperature deduced from the Manchester method or its modification to approximate the continuum under the 30{mu}m feature. We find that the strength of the 30{mu}m feature increases until dust temperature drops below 400K. Below this temperature, the large loss of mass and probably the self-absorption effect reduces the strength of the feature. During the post-AGB phase, when the intense mass-loss has terminated, the optical depth of the circumstellar envelope is smaller, and the 30{um}m feature becomes visible again, showing variety of values for post-AGB objects and PNe, and being comparable with the strengths of AGB stars. In addition, the AGB stars and post-AGB objects show similar values of central wavelengths - usually between 28.5 and 29.5{mu}m. However, in case of PNe the shift of the central wavelength towards longer wavelengths is visible. The normalised median profiles for AGB stars look uniformly for various ranges of dust temperature, and different galaxies. We analysed the profiles of post-AGB objects and PNe only within one dust temperature range (below 200K), and they were also similar in different galaxies. In the spectra of 17 PNe and five post-AGB objects we found the broad 16-24{mu}m feature. Two objects among the PNe group are the new detections: SMP LMC 51, and SMP LMC 79, whereas in the case of post-AGBs the new detections are: IRAS 05370-7019, IRAS 05537-7015, and IRAS 21546+4721. In addition, in the spectra of nine PNe we found the new detections of 16-18{mu}m feature. We also find that the Galactic post-AGB object IRAS 11339-6004 has a 21{mu}m emission. Finally, we have produced online catalogues of photometric data and Spitzer IRS spectra for all objects that show the 30{mu}m feature. These resources are available online for use by the community. The most important conclusion of our work is the fact that the formation of the 30{mu}m feature is affected by metallicity. Specifically that, as opposed to more metal-poor samples of AGB stars in the MCs, the feature is seen at lower mass-loss rates, higher temperatures, and has seen to be more prominent in Galactic carbon stars. The averaged feature (profile) in the AGB, post-AGB objects, and PNe seems unaffected by metallicity at least between a fifth and solar metallicity, but in the case of PNe it is shifted to significantly longer wavelengths.