- ID:
- ivo://CDS.VizieR/J/A+A/638/A84
- Title:
- PACS observations of large main-belt asteroids
- Short Name:
- J/A+A/638/A84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Non-resolved thermal infrared observations enable studies of thermal and physical properties of asteroid surfaces provided the shape and rotational properties of the target are well determined via thermo-physical models. We used calibration-programme Herschel PACS data (70, 100, 160 microns) and state-of-the-art shape models derived from adaptive-optics observations and/or optical light curves to constrain for the first time the thermal inertia of twelve large main-belt asteroids. We also modelled previously well-characterised targets such as (1) Ceres or (4) Vesta as they constitute important benchmarks. Using the scale as a free parameter, most targets required a re-scaling ~5% consistent with what would be expected given the absolute calibration error bars. This constitutes a good cross-validation of the scaled shape models, although some targets required larger re-scaling to reproduce the IR data. We obtained low thermal inertias typical of large main belt asteroids studied before, which continues to give support to the notion that these surfaces are covered by fine-grained insulating regolith. Although the wavelengths at which PACS observed are longwards of the emission peak for main-belt asteroids, they proved to be extremely valuable to constrain size and thermal inertia and not too sensitive to surface roughness. Finally, we also propose a graphical approach to help examine how different values of the exponent used for scaling the thermal inertia as a function of heliocentric distance (i.e. temperature) affect our interpretation of the results.
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- ID:
- ivo://CDS.VizieR/J/A+A/613/A40
- Title:
- PACS photometry of FIR faint stars
- Short Name:
- J/A+A/613/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our aims are to determine flux densities and their photometric accuracy for a set of seventeen stars that range in flux from intermediately bright (<~2.5Jy) to faint (>~5mJy) in the far-infrared (FIR). We also aim to derive signal-to-noise dependence with flux and time, and compare the results with predictions from the Herschel exposure-time calculation tool. We obtain aperture photometry from Herschel-PACS high-pass-filtered scan maps and chop/nod observations of the faint stars. The issues of detection limits and sky confusion noise are addressed by comparison of the field-of-view at different wavelengths, by multi-aperture photometry, by special processing of the maps to preserve extended emission, and with the help of large-scale absolute sky brightness maps from AKARI. This photometry is compared with flux-density predictions based on photospheric models for these stars. We obtain a robust noise estimate by fitting the flux distribution per map pixel histogram for the area around the stars, scaling it for the applied aperture size and correcting for noise correlation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/727
- Title:
- Padova-Millennium Galaxy and Group Catalogue
- Short Name:
- J/MNRAS/416/727
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the construction and describe the properties of the Padova-Millennium Galaxy and Group Catalogue (PM2GC), a galaxy catalogue representative of the general field population in the local Universe. We characterize galaxy environments by identifying galaxy groups at 0.04<=z<=0.1 with a Friends-of-Friends (FoF) algorithm using a complete sample of 3210 galaxies brighter than M_B_=-18.7 taken from the Millennium Galaxy Catalogue (MGC, Liske et al., 2003, Cat. VII/240), a 38deg^2^ image photometric and spectroscopic equatorial survey. We identified 176 groups with at least three members, comprising in total 1057 galaxies and representing ~43 per cent of the general field population in that redshift range.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/2006
- Title:
- PAH in extragalactic star-forming complexes
- Short Name:
- J/MNRAS/431/2006
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The abundance of polycyclic aromatic hydrocarbons (PAHs) in low- and high-metallicity galaxies has been widely discussed since the time when detailed infrared data for extragalactic objects were first obtained. On the scales of entire galaxies, a smaller PAH abundance in lower metallicity galaxies is often observed. We study this relationship for star-forming regions in nearby galaxies, for a sample containing more than 200 HII complexes, using spatially resolved observations from the Herschel Space Observatory and Spitzer Space Telescope. We use a model for the dust emission to estimate the physical parameters (PAH abundance, metallicity, ultraviolet radiation field, etc.) of these complexes. The same correlation of PAH abundance with metallicity, as seen for entire galaxies, is apparently preserved at smaller scales, at least when the Kobulnicky and Kewley metallicity calibration is used. We discuss possible reasons for this correlation, noting that traces of less effective PAH formation in low-metallicity asymptotic giant branch stars should be smeared out by radial mixing in galactic discs. Effective destruction by the harder and more intensive ultraviolet field in low-metallicity environments is qualitatively consistent with our data, as the ultraviolet field intensity, derived from the infrared photometry, is indeed smaller in HII complexes with lower metallicity.
- ID:
- ivo://CDS.VizieR/J/A+A/514/A5
- Title:
- PAH luminous galaxies at z~1
- Short Name:
- J/A+A/514/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The NEP-deep survey, an extragalactic AKARI survey towards the north ecliptic pole (NEP), provides a comprehensive wavelength coverage from 2 to 24um using all 9 photometric bands of the infrared camera (IRC). It allows us to photometrically identify galaxies whose mid-IR emission is clearly dominated by PAHs. We propose a single-colour selection method to identify such galaxies, using two mid-IR flux ratios at 11-to-7um and 15-to-9um (PAH-to-continuum flux ratio in the rest frame), which are useful for identifying starburst galaxies at z~0.5 and 1, respectively. We perform a fitting of the spectral energy distributions (SEDs) from optical to mid-IR wavelengths, using an evolutionary starburst model with a proper treatment of radiative transfer (SBURT), in order to investigate their nature.
- ID:
- ivo://CDS.VizieR/J/PASJ/65/103
- Title:
- PAH3.3um/IR luminosity for infrared galaxies
- Short Name:
- J/PASJ/65/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For star-forming galaxies, we investigated a global relation between the polycyclic aromatic hydrocarbon (PAH) emission luminosity at 3.3um, L_PAH3.3_, and the infrared (8-1000um) luminosity, L_IR_, to understand how the PAH 3.3um feature relates to star-formation activity. With AKARI, we performed near-infrared (2.5-5um) spectroscopy of 184 galaxies having L_IR_~10^8^-10^13^L_{sun}_. We classified the samples into infrared galaxies (IRGs: L_IR_<10^11^L_{sun}_), luminous infrared galaxies (LIRGs: L_IR_~10^11^-10^12^L_{sun}_ and ultra-luminous infrared galaxies (ULIRGs: L_IR_>10^12^L_{sun}_). We excluded sources likely to be contaminated by AGN activity, based on the rest-frame equivalent width of the PAH emission feature (<40nm) and the power-law index, representing the slope of continuum emission ({Gamma}>; F{nu}{prop.to}{lambda}^{Gamma}). Of these samples, 13 IRGs, 67 LIRGs, and 20 ULIRGs show the PAH emission feature at {lambda}_rest_=3.3um in their spectra. We find that the L_PAH3.3_/L_IR_ ratio considerably decreases toward the luminous end. Utilizing the mass and temperature of dust grains as well as the Br{alpha} emission for the galaxies, we discuss the cause of the relative decrease in the PAH emission with L_IR_.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/347.365
- Title:
- Paired galaxies and their supernovae
- Short Name:
- J/other/ApSS/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the influence of close neighbor galaxies on the properties of supernovae (SNe) and their host galaxies using 56 SNe located in pairs of galaxies with different levels of star formation (SF) and nuclear activity. The statistical study of SN hosts shows that there is no significant difference between morphologies of hosts in our sample and the larger general sample of SN hosts in the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). The mean distance of type II SNe from nuclei of hosts is greater by about a factor of 2 than that of type Ibc SNe. The distributions and mean distances of SNe are consistent with previous results compiled with the larger sample. For the first time it is shown that SNe Ibc are located in pairs with significantly smaller difference of radial velocities between components than pairs containing SNe Ia and II. We consider this as a result of higher star formation rate (SFR) of these closer systems of galaxies. SN types are not correlated with the luminosity ratio of host and neighbor galaxies in pairs. The orientation of SNe with respect to the preferred direction toward neighbor galaxy is found to be isotropic and independent of kinematical properties of the galaxy pair.
4838. Pairs of QSO in SDSS-DR4
- ID:
- ivo://CDS.VizieR/J/ApJ/658/99
- Title:
- Pairs of QSO in SDSS-DR4
- Short Name:
- J/ApJ/658/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study quasar clustering on small scales, modeling clustering amplitudes using halo-driven dark matter descriptions. From 91 pairs n scales <35h^-1^kpc, we detect only a slight excess in quasar clustering over our best-fit large-scale model. Integrated across all redshifts, the implied quasar bias is bQ=4.21+/-0.98 (bQ=3.93+/-0.71) at ~18h^-1^kpc (~28h^-1^kpc).
- ID:
- ivo://CDS.VizieR/J/AJ/128/3019
- Title:
- Pal 13 blue stragglers and main-sequence binaries
- Short Name:
- J/AJ/128/3019
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-precision VI photometry of stars from the middle of the giant branch to about 5mag below the main-sequence turnoff in the globular cluster Palomar 13 based on images obtained with the Keck II 10m telescope. We tabulate a complete sample of blue stragglers in the cluster out to about 18 core radii.
- ID:
- ivo://CDS.VizieR/II/207A
- Title:
- Palomar-Green catalog UV-excess stellar objects
- Short Name:
- II/207A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Palomar-Green Catalogue of UV-excess stellar objects provides positions accurate to about 8arcsec in each coordinate, photographic B-magnitudes accurate to 0.29mag, spectral types, some cross-references, and photoelectric broad-band, multichannel, and Stroemgren colors when available. Of the 1874 objects in the catalogue as published in 1986 (1878 in this version), 1715 comprise a statistically complete sample covering 10714 square degrees from 266 fields taken on the Palomar 18-inch Schmidt telescope. Limiting magnitudes vary from field to field, ranging from 15.49 to 16.67. The overall completeness is estimated to be 84%, but that figure and the relative contributions of magnitude, color, and accidental errors vary depending on the magnitude and color distribution of the spectroscopic subsample.
