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- ID:
- ivo://CDS.VizieR/J/AJ/129/2074
- Title:
- Faint Chandra sources in SWIRE
- Short Name:
- J/AJ/129/2074
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We exploit deep combined observations with Spitzer and Chandra of the Spitzer Wide-Area Infrared Extragalactic Survey (SWIRE) in the ELAIS N1 region to investigate the nature of the faint X-ray and IR sources in common, to identify active galactic nucleus (AGN)/starburst diagnostics, and to study the sources of the X-ray and IR cosmic backgrounds (XRB and CIRB).
- ID:
- ivo://CDS.VizieR/J/PASJ/60/209
- Title:
- Faint companions around YSOs in TMC
- Short Name:
- J/PASJ/60/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted near-infrared spectroscopy of 26 faint objects around young stellar objects in the Taurus molecular cloud. These objects were detected during a course of near-infrared coronagraphic searches for companions around 72 young stellar objects with the Subaru Telescope and the near-infrared coronagraph CIAO (coronagraphic imager with adaptive optics). A comparison of the Subaru and HST archive images revealed that three central stars and faint companions share common proper motions, suggesting that they are physically associated with each other. None of the 26 sources show deep water absorption bands at near-infrared, except for DH Tau B. This result indicates that all of them, but DH Tau B, have a high photospheric temperature or a large amount of excess from circumstellar materials.
- ID:
- ivo://CDS.VizieR/J/ApJ/405/94
- Title:
- Far-infrared emission from 5 galaxy clusters
- Short Name:
- J/ApJ/405/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have analyzed IRAS image data using a random position, multiple-aperture photometry method to study diffuse far-infrared emission for a sample of 56 clusters of galaxies at 60 and 100um. Five of the clusters in the sample exhibit excess far-infrared emission, but at low levels of significance. For A496 (Perseus) and MKW 1, this emission appears to be associated with a strong point source: in A2344, the observed excess is probably due to a foreground cirrus cloud. Two clusters, A262 and A2670, show evidence for extended diffuse emission. This emission is unlikely to be due to point sources associated with the clusters. In these two clusters, the diffuse emission shows evidence of being extended along the cluster's major axis. Far-infrared maps at 60 and 100um are presented for these five clusters. We find that contamination due to diffuse Galactic cirrus represents the major source of uncertainty in the measurement of far-infrared emission. The mean cluster fluxes for the sample as a whole are 44 and 107mJy for a 4' diameter aperture at 60 and 100um, respectively. The corresponding fluxes for a 10' diameter aperture are 138 and 253mJy at 60 and 100um. Photometry for the entire sample shows statistical evidence for excess emission at 60um associated with clusters in apertures 4' and 10' in diameter. This result is unlikely to be caused by random sampling errors. The flux distributions are analyzed for evidence that excess far-infrared radiation correlates with cluster environmental characteristics. Although we find evidence that poorer X-ray clusters are stronger far-infrared emitters, this result is tentative owing to the small sample sizes involved. The far-infrared luminosities, dust temperatures, and dust masses which these results imply are also presented. Finally, the origin and possible heating mechanism for dust in the intracluster medium is discussed.
- ID:
- ivo://CDS.VizieR/J/A+A/418/131
- Title:
- Far-infrared loops in the 2nd Galactic Quadrant
- Short Name:
- J/A+A/418/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an investigation of the large structure of the diffuse interstellar medium in the 2nd Galactic Quadrant (90{deg}<=l<=180{deg}). 145 loops were identified on IRAS based on far-infrared maps. Our catalogue lists their basic physical properties. The distribution clearly suggests that there is an efficient process that can generate loop-like features at high galactic latitudes. Distances are provided for 30 loops. We also give an observational estimate on the volume filling factor of the hot gas in the Local Arm, 4.6%<=f_2nd_<6.4%.
- ID:
- ivo://CDS.VizieR/J/ApJ/869/4
- Title:
- Far-infrared SED measurements of massive galaxies
- Short Name:
- J/ApJ/869/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Massive Population II galaxies undergoing the first phase of vigorous star formation after the initial Population III stage should have high energy densities and silicate-rich interstellar dust. We have modeled the resulting far-infrared spectral energy distributions (SEDs), demonstrating that they are shifted substantially to bluer ("warmer") wavelengths relative to the best fitting ones at z~3, and with strong outputs in the 10-40{mu}m range. When combined with a low level of emission by carbon dust, their SEDs match that of Haro 11, a local moderately low-metallicity galaxy undergoing a very young and vigorous starburst that is likely to approximate the relevant conditions in young Population II galaxies. We expect to see similar SEDs at high redshifts (z>~5) given the youth of galaxies at this epoch. In fact, we find a progression with redshift in observed galaxy SEDs, from those resembling local ones at 2<~z<4 to a closer resemblance with Haro 11 at 5<~z<7. In addition to the insight on conditions in high-redshift galaxies, this result implies that estimates of the total infrared luminosities at z~6 based on measurements near {lambda}~1mm can vary by factors of 2-4, depending on the SED template used. Currently popular modified blackbodies or local templates can result in significant underestimates compared with the preferred template based on the SED of Haro 11.
- ID:
- ivo://CDS.VizieR/J/other/PBeiO/18.7
- Title:
- Far infrared Seyfert galaxies
- Short Name:
- J/other/PBeiO/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Confusing sources of Seyfert and HII galaxies in IRAS point source catalogue may be caused by companion objects of those galaxies. Comparison between confused galaxies and non-confused galaxies have been made. The preliminary comparison shows that confused galaxies are fainter than nonconfused galaxies generally, and colour diagrams illustrate that confused Seyferts are separated from nonconfused Seyferts obviously.
- ID:
- ivo://CDS.VizieR/J/A+A/594/A59
- Title:
- Far-IR lines in YSOs Herschel-PACS
- Short Name:
- J/A+A/594/A59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Gas plays a major role in the dynamical evolution of young stellar objects (YSOs). Its interaction with the dust is the key to our understanding planet formation later on in the protoplanetary disc stage. Studying the gas content is therefore a crucial step towards understanding YSO and planet formation. Such a study can be made through spectroscopic observations of emission lines in the far-infrared, where some of the most important gas coolants emit, such as the [OI] ^3^P_1_-^3^P_2_ transition at 63.18 microns. We provide a compilation of observations of far-IR lines in 362 young stellar objects covering all evolutionary stages, from Class 0 to Class III with debris discs. In the present paper we focus on [OI] and o-H_2_O emission at 63 microns. We have retrieved all the available Herschel-PACS spectroscopic observations at 63 microns that used the dominant observing mode, the chop-nod technique. We provide measurements of line fluxes for the [OI] ^3^P_1_-^3^P_2_ and o-H_2_O 8_08_-7_17_ transitions at 63 microns computed using different methods. Taking advantage of the PACS IFU, we check for spatially extended emission and further study the presence of multiple dynamical components in line emission. The final compilation consists of line and continuum fluxes at 63 microns for a total of 362 young stellar objects (YSOs). We detected [OI] line emission at 63 microns in 194 sources out of 362, and line absorption in another five sources. o-H_2_O was detected in 42 sources. We find evidence of extended [OI] emission in 77 sources, and detect 3sigma residual emission in 71 of them. The number of sources showing extended emission decays from Class 0 to Class II. We also looked for different components contributing to the line emission, and found evidence for multiple components in 30 sources. We explored correlations between line emission and continuum emission and find a clear correlation between WISE fluxes from 4.6 to 22 microns and [OI] line emission. We conclude that the observed emission is typically a combination of disc/envelope and jet emission.
- ID:
- ivo://CDS.VizieR/J/ApJ/714/1256
- Title:
- Far-IR star formation rate indicators
- Short Name:
- J/ApJ/714/1256
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spitzer data at 24, 70, and 160um and ground-based H{alpha} images are analyzed for a sample of 189 nearby star-forming and starburst galaxies to investigate whether reliable star formation rate (SFR) indicators can be defined using the monochromatic infrared dust emission centered at 70 and 160um. We compare recently published recipes for SFR measures using combinations of the 24um and observed H{alpha} luminosities with those using 24um luminosity alone. From these comparisons, we derive a reference SFR indicator for use in our analysis. Linear correlations between SFR and the 70um and 160um luminosity are found for L(70)>~1.4x10^42^erg/s and L(160)>~2x10^42^erg/s, corresponding to SFR>~0.1-0.3M_{sun}_/yr, and calibrations of SFRs based on L(70) and L(160) are proposed. Below those two luminosity limits, the relation between SFR and 70um (160um) luminosity is nonlinear and SFR calibrations become problematic. A more important limitation is the dispersion of the data around the mean trend, which increases for increasing wavelength.
- ID:
- ivo://CDS.VizieR/J/A+A/413/843
- Title:
- Far IR survey in the Lockman Hole
- Short Name:
- J/A+A/413/843
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalogs and source counts for the C_90_ (reference wavelength of 90um) and C_160_ (170um) bands, which were extracted from our analysis of an ISO deep far-infrared survey conducted as part of the Japan/UH ISO cosmology project. The total survey area is ~0.9deg^2^ in two fields within the Lockman Hole. The analysis consists of source extraction using the IRAF DAOPHOT package and simulations carried out by adding artificial sources to the maps to estimate the detection rate, the flux bias, the positional accuracy, and the noise.