- ID:
- ivo://CDS.VizieR/J/A+A/597/A51
- Title:
- Physical properties of Spitzer/IRS galaxies
- Short Name:
- J/A+A/597/A51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide the basic integrated physical properties of all the galaxies contained in the full Cornell Atlas of Spitzer/IRS Sources (CASSIS) with available broad-band photometry from UV to 22 microns. We have collected broad-band photometric measurements in 14 wavelengths from available public surveys in order to study the spectral energy distribution (SED) of each galaxy in CASSIS, thus constructing a final sample of 1146 galaxies in the redshift range 0<z<2.5. The SEDs are modelled with the CIGALE code which relies on the energy balance between the absorbed stellar and the dust emission while taking into account the possible contribution due to the presence of an active galactic nucleus (AGN). We split the galaxies in three groups, a low-redshift (z<0.1), a mid-redshift (0.1=<z<0.5) and a high-redshift (z>=0.5) sub-sample and find that the vast majority of the Spitzer/IRS galaxies are star-forming and lie on or above the star-forming main sequence of the corresponding redshift. Moreover, the emission of Spitzer/IRS galaxies with z<0.1 is mostly dominated by star-formation, galaxies in the mid-redshift bin are a mixture of star forming and AGN galaxies, while half of the galaxies with z>=0.5 show moderate or high AGN activity. Additionally, using rest-frame NUV-r colour, Sersic indices, optical [OIII] and [NII] emission lines we explore the nature of these galaxies by investigating further their structure as well as their star-formation and AGN activity. Using a colour magnitude diagram we confirm that 97% of the galaxies with redshift smaller than 0.5 have experienced a recent star-formation episode. For a sub-sample of galaxies with available structural information and redshift smaller than 0.3 we find that early-type galaxies are placed below the main sequence, while late-type galaxies are found on the main- sequence as expected. Finally, for all the galaxies with redshift smaller than 0.5 and available optical spectral line measurements we compare the ability of CIGALE to detect the presence of an AGN in contrast to the optical spectra classification. We find that galaxies with high AGN luminosity, as calculated by CIGALE, are most likely to be classified as composite or AGNs by optical spectral lines.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/736/119
- Title:
- Pioneer 10/11 IPP sky brightness maps
- Short Name:
- J/ApJ/736/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the new constraints on the cosmic optical background (COB) obtained from an analysis of the Pioneer 10/11 Imaging Photopolarimeter (IPP) data. After careful examination of data quality, the usable measurements free from the zodiacal light are integrated into sky maps at the blue (~0.44um) and red (~0.64um) band. Accurate starlight subtraction is achieved by referring to all-sky star catalogs and a Galactic stellar population synthesis model down to 32.0mag. We find that the residual light is separated into two components: one component shows a clear correlation with thermal 100um brightness, while another betrays a constant level in the lowest 100um brightness region. The presence of the second component is significant after all the uncertainties and possible residual light in the Galaxy are taken into account, and thus it most likely has the extragalactic origin (i.e., the COB).
- ID:
- ivo://CDS.VizieR/J/A+A/626/A90
- Title:
- Pismis 18 photometry and radial velocities
- Short Name:
- J/A+A/626/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Pismis 18 is a moderately populated, intermediate-age open cluster located within the solar circle at a Galactocentric distance of about seven kpc. Few open clusters have been studied in detail in the inner disc region before the Gaia-ESO Survey. New data from the Gaia-ESO Survey allowed us to conduct an extended radial velocity membership study as well as spectroscopic metallicity and detailed chemical abundance measurements for this cluster. Gaia-ESO Survey data for 142 potential members, lying on the upper main sequence and on the red clump, yielded radial velocity measurements, which, together with proper motion measurements from the Gaia Second Data Release (Gaia DR2), were used to determine the systemic velocity of the cluster and membership of individual stars. Photometry from Gaia DR2 was used to re-determine cluster parameters based on high confidence member stars only. Cluster abundance measurements of six radial-velocity member stars with UVES high-resolution spectroscopy are presented for 23 elements. The average radial velocity of 26 high confidence members is -27.5+/-2.5(std)km/s with an average proper motion of pmra=-5.65+/-0.08(std)mas/yr and pmdec=-2.29+/-0.11(std)mas/yr. According to the new estimates, based on high confidence members, Pismis 18 has an age of {tau}=700^+40^_-50_Myr, interstellar reddening of E(B-V)=0.562^+0.012^_-0.026_mag and a de-reddened distance modulus of DM_0_=11.96^+0.10^_-0.24_mag. The median metallicity of the cluster (using the six UVES stars) is [Fe/H]=+0.23+/-0.05dex, with [{alpha}/Fe]=0.07+/-0.13 and a slight enhancement of s- and r- neutron-capture elements. With the present work, we fully characterized the open cluster Pismis 18.We confirmed its present location in the inner disc. We estimated a younger age than the previous literature values and we gave, for the first time, its metallicity and its detailed abundances. Its [{alpha}/Fe] and [s-process/Fe], both slightly super-solar, are in agreement with other inner-disc open clusters observed by the Gaia-ESO survey.
- ID:
- ivo://CDS.VizieR/J/A+A/539/A119
- Title:
- Pismis 24 stars with X-ray emission
- Short Name:
- J/A+A/539/A119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Circumstellar disks are expected to evolve quickly in massive young clusters harboring many OB-type stars. Two processes have been proposed to drive the disk evolution in such cruel environments: (1) gravitational interaction between circumstellar disks and nearby passing stars (stellar encounters), and (2) photoevaporation by UV photons from massive stars. The relative importance of both mechanisms is not well understood. Studies of massive young star clusters can provide observational constraints on the processes of driving disk evolution. We investigate the properties of young stars and their disks in the NGC 6357 complex, concentrating on the most massive star cluster within the complex: Pismis 24.
- ID:
- ivo://CDS.VizieR/J/AJ/141/137
- Title:
- Pittsburgh SDSS Mg II QSO catalog
- Short Name:
- J/AJ/141/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of intervening Mg II quasar absorption-line systems in the redshift interval 0.36<=z<=2.28. The catalog was built from Sloan Digital Sky Survey Data Release Four (SDSS DR4, Cat. II/267) quasar spectra. Currently, the catalog contains ~17000 measured Mg II doublets. We also present data on the ~44600 quasar spectra which were searched to construct the catalog, including redshift and magnitude information, continuum-normalized spectra, and corresponding arrays of redshift-dependent minimum rest equivalent widths detectable at our confidence threshold. The catalog is available online. A careful second search of 500 random spectra indicated that, for every 100 spectra searched, approximately one significant Mg II system was accidentally rejected. Current plans to expand the catalog beyond DR4 quasars are discussed. Many Mg II absorbers are known to be associated with galaxies. Therefore, the combination of large size and well understood statistics makes this catalog ideal for precision studies of the low-ionization and neutral gas regions associated with galaxies at low to moderate redshift. An analysis of the statistics of Mg II absorbers using this catalog will be presented in a subsequent paper.
- ID:
- ivo://CDS.VizieR/J/MNRAS/433/1709
- Title:
- PKS 0558-504 UVOT and XRT monitoring
- Short Name:
- J/MNRAS/433/1709
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- PKS 0558-504 is a highly-variable, X-ray-bright, radio-loud, narrow-line Seyfert 1 galaxy with super-Eddington accretion rate and extended jets that do not dominate the emission beyond the radio band. Therefore, this source represents an ideal laboratory to shed some light on the central engine in highly accreting systems and specifically on the link between accretion disc and corona. Here we present the results from a 1.5-year monitoring with Swift-XRT and Swift-UVOT. The simultaneous coverage at several wavelengths confirms that PKS 0558-504 is highly variable in any band from the optical to ultraviolet (UV) and X-rays, with the latter showing the largest amplitude changes but with the UV emission dominating the radiative output. A cross-correlation analysis reveals a tight link between the emission in the optical and UV bands and provides suggestive evidence in favour of a scenario where the variability originates in the outer part of the accretion flow and propagates inwards before triggering the activity of the X-ray-emitting corona. Finally, a positive correlation between the soft-X-ray flux and the hard photon index suggests that in PKS 0558-504 the seed photons are provided to the corona by the soft-excess component.
- ID:
- ivo://CDS.VizieR/J/A+A/604/A65
- Title:
- Planck and Herschel images combination
- Short Name:
- J/A+A/604/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Herschel has revolutionized our ability to measure column densities (N_H_) and temperatures (T) of molecular clouds thanks to its far infrared multiwavelength coverage. However, the lack of a well defined background intensity level in the Herschel data limits the accuracy of the NH and T maps. We aim to provide a method that corrects the missing Herschel background intensity levels using the Planck model for foreground Galactic thermal dust emission. For the Herschel/PACS data, both the constant-offset as well as the spatial dependence of the missing background must be addressed. For the Herschel/SPIRE data, the constant-offset correction has already been applied to the archival data so we are primarily concerned with the spatial dependence, which is most important at 250um. We present a Fourier method that combines the publicly available Planck model on large angular scales with the Herschel images on smaller angular scales. We have applied our method to two regions spanning a range of Galactic environments: Perseus and the Galactic plane region around l=11{deg} (HiGal-11). We post-processed the combined dust continuum emission images to generate column density and temperature maps. We compared these to previously adopted constant-offset corrections. We find significant differences (>~20%) over significant (~15%) areas of the maps, at low column densities (N_H_<~10^22^cm^-2^) and relatively high temperatures (T>~20K). We have also applied our method to synthetic observations of a simulated molecular cloud to validate our method. Our method successfully corrects the Herschel images, including both the constant-offset intensity level and the scale-dependent background variations measured by Planck. Our method improves the previous constant-offset corrections, which did not account for variations in the background emission levels.
- ID:
- ivo://CDS.VizieR/J/ApJ/864/154
- Title:
- Planck cold clump G108.37-01.06 YSO candidates
- Short Name:
- J/ApJ/864/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Planck Galactic Cold Clumps (PGCCs) are possible representations of the initial conditions and very early stages of star formation. With the objective of understanding better the star and star cluster formation, we probe the molecular cloud associated with PGCC G108.37-01.06 (hereafter PG108.3), which can be traced in a velocity range of -57 to -51km/s. The INT Photometric H{alpha} Survey images reveal H{alpha} emission at various locations around PG108.3, and optical spectroscopy of the bright sources in those zones of H{alpha} emission discloses two massive ionizing sources with spectral type O8-O9V and B1V. Using the radio continuum, we estimate ionizing gas parameters and find the dynamical ages of HII regions associated with the massive stars in the range of 0.5-0.75Myr. Based on the stellar surface density map constructed from the deep near-infrared Canada-France-Hawaii Telescope observations, we find two prominent star clusters in PG108.3; of these, the cluster associated with H ii region S148 is moderately massive (~240M_{sun}_). A careful inspection of James Clerk Maxwell telescope ^13^CO (3-2) molecular data exhibits that the massive cluster is associated with a number of filamentary structures. Several embedded young stellar objects (YSOs) are also identified in PG108.3 along the length and junction of filaments. We find evidence of a velocity gradient along the length of the filaments. Along with kinematics of the filaments and the distribution of ionized, molecular gas and YSOs, we suggest that the cluster formation is most likely due to the longitudinal collapse of the most massive filament in PG108.3.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A106
- Title:
- Planck submillimetre sources in Virgo Cluster
- Short Name:
- J/A+A/562/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We cross-correlate the Planck Catalogue of Compact Sources (PCCS) with the fully sampled 84deg^2^ Herschel Virgo Cluster Survey (HeViCS) fields. We search for and identify the 857 and 545GHz PCCS sources in the HeViCS fields by studying their FIR/submm and optical counterparts. We find 84 and 48 compact Planck sources in the HeViCS fields at 857 and 545GHz, respectively. Almost all sources correspond to individual bright Virgo Cluster galaxies. The vast majority of the Planck detected galaxies are late-type spirals, with the Sc class dominating the numbers, while early-type galaxies are virtually absent from the sample, especially at 545GHz. We compare the HeViCS SPIRE flux densities for the detected galaxies with the four different PCCS flux density estimators and find an excellent correlation with the aperture photometry flux densities, even at the highest flux density levels. We find only seven PCCS sources in the HeViCS fields without a nearby galaxy as obvious counterpart, and conclude that all of these are dominated by Galactic cirrus features or are spurious detections. No Planck sources in the HeViCS fields seem to be associated to high-redshift proto-clusters of dusty galaxies or strongly lensed submm sources. Finally, our study is the first empirical confirmation of the simulation-based estimated completeness of the PCCS, and provides a strong support of the internal PCCS validation procedure.
- ID:
- ivo://CDS.VizieR/J/AJ/156/22
- Title:
- Planetary candidates from K2 Campaign 16
- Short Name:
- J/AJ/156/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Given that Campaign 16 of the K2 mission is one of just two K2 campaigns observed so far in "forward-facing" mode, which enables immediate follow-up observations from the ground, we present a catalog of interesting targets identified through photometry alone. Our catalog includes 30 high-quality planet candidates (showing no signs of being non-planetary in nature), 48 more ambiguous events that may be either planets or false positives, 164 eclipsing binaries, and 231 other regularly periodic variable sources. We have released light curves for all targets in C16 and have also released system parameters and transit vetting plots for all interesting candidates identified in this paper. Of particular interest is a candidate planet orbiting the bright F dwarf HD 73344 (V=6.9, K=5.6) with an orbital period of 15 days. If confirmed, this object would correspond to a 2.56+/-0.18 R_{Earth}_ planet and would likely be a favorable target for radial velocity characterization. This paper is intended as a rapid release of planet candidates, eclipsing binaries, and other interesting periodic variables to maximize the scientific yield of this campaign, and as a test run for the upcoming TESS mission, whose frequent data releases call for similarly rapid candidate identification and efficient follow up.