- ID:
- ivo://CDS.VizieR/J/AJ/104/704
- Title:
- A VLA Search for Young Galactic Supernova Remnants
- Short Name:
- J/AJ/104/704
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the attempt to identify very young galactic supernova remnants (SNRs), 290 known compact (<2') galactic plane radio sources were observed at 20cm using the VLA in its 36 km configuration. The VLA observations described could detect supernovae with diameters between 5 and 20"; these would have an age of between 25 and 100 yr. Compact structure was detected in 168 (58%) of the 290 different sources observed; 73 sources (25%) were unresolved or slightly resolved point sources, 21 (7%) were single-well resolved, 56 (19%) were double, 18 (6%) were triple or complex. The large scale structure was completely resolved out for 122 (42%) of sources. Additional observations at 6cm with the VLA in the 11 km configuration were made of 14 sources with apparent shell structures that might have been characteristic of young SNRs. Low resolution observations were made at 20cm of 62 fields where the source was completely resolved out in the high resolution images. Only one source, G25.5+0.2, is a possible very young SNR. New H66_alpha recombination line observations place severe constrains on any thermal interpretation for this object.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/154/252
- Title:
- A VLA survey of magnetic CVs. I. The data
- Short Name:
- J/AJ/154/252
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Jansky Very Large Array was used to observe 121 magnetic cataclysmic variables (MCVs). We report radio detections of 18 stars. Thirteen are new radio sources, increasing the number of MCVs that are radio sources by more than twofold, from 8 to 21. Most detections are at 8.7 GHz (X-band) with a lesser number at 5.4 and 21.1 GHz (C- and K-bands). With the exception of AE Aqr, whose flux density is typically >5 mJy, the flux densities are in the range of 24-780 {mu}Jy. Thirteen of the detections show highly circularly polarized emission, which is characteristic of electron-cyclotron maser emission. The data suggest that MCVs could possibly be divided into two classes of radio emitters: those dominated by weakly polarized gyrosynchrotron emission and those by highly polarized electron-cyclotron maser emission.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A145
- Title:
- A WISE view on extreme AGB stars
- Short Name:
- J/A+A/659/A145
- Date:
- 18 Mar 2022 08:25:03
- Publisher:
- CDS
- Description:
- Variability is a key property of stars on the asymptotic giant branch (AGB). Their pulsation period is related to the luminosity and mass-loss rate (MLR) of the star. Long-period variables (LPVs) and Mira variables are the most prominent of all types of variability of evolved stars. However, the reddest, most obscured AGB stars are too faint in the optical and have eluded large variability surveys. Our goal is to obtain a sample of LPVs with large MLRs by analysing WISE W1 and W2 light curves (LCs) for about 2000 sources, photometrically selected to include known C-stars with the 11.3 micron silicon carbide dust feature in absorption, and Galactic O-stars with periods longer than 1000 days. Epoch photometry was retrieved from the AllWISE and NEOWISE database and fitted with a sinus curve. Photometry from other variability surveys was also downloaded and fitted. For a subset of 316 of the reddest stars, spectral energy distributions (SEDs) were constructed, and, together with mid-infrared (MIR) spectra when available, fitted with a dust radiative transfer programme in order to derive MLRs. WISE based LCs and fits to the data are presented for all stars. Periods from the literature and periods from refitting other literature data are presented. The results of the spatial correlation with several (IR) databases is presented. About one-third of the sources are found to be not real, but it appears that these cannot be easily filtered out by using WISE flags. Some are clones of extremely bright sources, and in some cases the LCs show the known pulsation period. Inspired by a recent paper, a number of non-variable OH/IRs are identified. Based on a selection on amplitude, a sample of about 750 (candidate) LPVs is selected of which 145 have periods beyond 1000 days, many of them being new. For the subset of the stars with the colours of C-rich extremely red objects (EROs) the fitting of the SEDs (and available MIR spectra) separates them into C- and O-rich objects. Interestingly, the fitting of MIR spectra of mass-losing C-stars is shown to be a powerful tracer of interstellar reddening when AV larger than 2 mag. The number of Galactic EROs appears to be complete up to about 5 kpc and a total dust return rate in the solar neighbourhood for this class is determined. In the LMC 12 additional EROs are identified. Although this represents only about 0.15% of the total known LMC C-star population adding their MLRs increases the previously estimated dust return by 8%. Based on the EROs in the Magellanic Clouds, a bolometric period luminosity is derived. It is pointed out that due to their faintness, EROs and similar O-rich objects are ideal targets for a NIR version of Gaia to obtain distances, observing in the K-band or, even more efficiently, in the L-band.
1154. AWM 7 radial velocities
- ID:
- ivo://CDS.VizieR/J/AJ/116/2108
- Title:
- AWM 7 radial velocities
- Short Name:
- J/AJ/116/2108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured redshifts and Kron-Cousins R-band magnitudes for a sample of galaxies in the poor cluster AWM 7. We have measured redshifts for 172 galaxies; 106 of these are cluster members. We determine the luminosity function (LF) from a photometric survey of the central 1.2x1.2h^-1^Mpc. The LF has a bump at the bright end and a faint-end slope of {alpha}=-1.37+/-0.16, populated almost exclusively by absorption-line galaxies. The cluster velocity dispersion is lower in the core (~530km/s) than at the outskirts (~680km/s), consistent with the cooling flow seen in the X-ray. The cold core extends ~150h^-1^kpc from the cluster center. The Kron-Cousins R-band mass-to-light ratio of the system is 650+/-170hM_{sun}_/L_{sun}_, substantially lower than previous optical determinations, but consistent with most previous X-ray determinations. We adopt H_0_=100hkm/s/Mpc throughout this paper; at the mean cluster redshift (5247+/-76km/s), 1h^-1^Mpc subtends 65.5'.
- ID:
- ivo://CDS.VizieR/J/ApJS/187/388
- Title:
- A XMM-Newton survey of the SXRB
- Short Name:
- J/ApJS/187/388
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present measurements of the soft X-ray background (SXRB) OVII and OVIII intensity between l=120{deg} and l=240{deg}, the first results of a survey of the SXRB using archival XMM-Newton observations. We do not restrict ourselves to blank-sky observations, but instead use as many observations as possible, removing bright or extended sources by hand if necessary. In an attempt to minimize contamination from near-Earth solar wind charge exchange (SWCX) emission, we remove times of high solar wind proton flux from the data. Without this filtering we are able to extract measurements from 586 XMM-Newton observations. With this filtering, ~1/2 of the observations are rendered unusable, and we are able to extract measurements from 303 observations. The oxygen intensities are typically ~0.5-10 photons/cm^2^/s/sr (line units, L.U.) for OVII and ~0-5L.U. for OVIII. The proton flux filtering does not systematically reduce the oxygen intensities measured from a given observation. However, the filtering does preferentially remove the observations with higher oxygen intensities. Our data set includes 69 directions with multiple observations, whose oxygen intensity variations can be used to constrain SWCX models. After removing observations likely to be contaminated by heliospheric SWCX emission, we use our results to examine the Galactic halo.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A121
- Title:
- Azimuthal anistropy of stellar galactic disks
- Short Name:
- J/A+A/618/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ellipsoid of stellar random motions is a fundamental ingredient of galaxy dynamics. Yet it has long been difficult to constrain this component in disks others than the Milky Way. This article presents the modeling of the azimuthal-to-radial axis ratio of the velocity ellipsoid of galactic disks from stellar dispersion maps using integral field spectroscopy data of the CALIFA survey. The measured azimuthal anisotropy is shown to be not strongly dependent on the assumed vertical-to-radial dispersion ratio of the ellipsoid. The anisotropy distribution shows a large diversity in the orbital structure of disk galaxies from tangential to radial stellar orbits. Globally, the orbits are isotropic in inner disk regions and become more radial as a function of radius, although this picture tends to depend on galaxy morphology and luminosity. The Milky Way orbital anisotropy profile measured from the Second Gaia Data Release is consistent with those of CALIFA galaxies. A new correlation is evidenced, linking the absolute magnitude or stellar mass of the disks to the azimuthal anisotropy. More luminous disks have more radial orbits and less luminous disks have isotropic and somewhat tangential orbits. This correlation is consistent with the picture in galaxy evolution in which orbits become more radial as the mass grows and is redistributed as a function of time. With the help of circular velocity curves, it is also shown that the epicycle theory fails to reproduce the diversity of the azimuthal anisotropy of stellar random motions, as it predicts only nearly radial orbits in the presence of flat curves. The origin of this conflict is yet to be identified. It also questions the validity of the vertical-to-radial axis ratio of the velocity ellipsoid derived by many studies in the framework of the epicyclic approximation.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/24
- Title:
- A z=0 Multiwavelength Galaxy Synthesis (z0MGS). I.
- Short Name:
- J/ApJS/244/24
- Date:
- 14 Mar 2022 07:45:54
- Publisher:
- CDS
- Description:
- We present an atlas of ultraviolet and infrared images of ~15750 local (d<~50Mpc) galaxies, as observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX) missions. These maps have matched resolution (FWHM 7.5" and 15"), matched astrometry, and a common procedure for background removal. We demonstrate that they agree well with resolved intensity measurements and integrated photometry from previous surveys. This atlas represents the first part of a program (the z=0 Multiwavelength Galaxy Synthesis) to create a large, uniform database of resolved measurements of gas and dust in nearby galaxies. This atlas allows us estimate local and integrated star formation rates (SFRs) and stellar masses (M_*_) across the local galaxy population in a uniform way. In the appendix, we use the population synthesis fits of Salim+ (2016ApJS..227....2S and 2018ApJ...859...11S) to calibrate integrated M_*_ and SFR estimators based on GALEX and WISE. Because they leverage a Sloan Digital Sky Survey (SDSS)-based training set of >100000 galaxies, these calibrations have high precision and allow us to rigorously compare local galaxies to SDSS results. We provide these SFR and M_*_ estimates for all galaxies in our sample and show that our results yield a "main sequence" of star-forming galaxies comparable to previous work. We also show the distribution of intensities from resolved galaxies in NUV-to-WISE1 versus WISE1-to-WISE3 space, which captures much of the key physics accessed by these bands.
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/102
- Title:
- AzTEC/ASTE 1.1mm observations in the ADF-S
- Short Name:
- J/MNRAS/411/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a 1.1-mm deep survey of the AKARI Deep Field South (ADF-S) with AzTEC mounted on the Atacama Submillimetre Telescope Experiment (ASTE). We obtained a map of 0.25-deg^2^ area with an rms noise level of 0.32-0.71mJy. This is one of the deepest and widest maps thus far at millimetre and submillimetre wavelengths. We uncovered 198 sources with a significance of 3.5{sigma}-15.6{sigma}, providing the largest catalogue of 1.1-mm sources in a contiguous region. Most of the sources are not detected in the far-infrared bands of the AKARI satellite, suggesting that they are mostly at z>=1.5 given the detection limits. We constructed differential and cumulative number counts in the ADF-S, the Subaru/XMM-Newton Deep Field and the SSA 22 field surveyed by AzTEC/ASTE, which provide currently the tightest constraints on the faint end.
- ID:
- ivo://CDS.VizieR/J/MNRAS/440/3462
- Title:
- AzTEC/ASTE 1.1mm survey of SSA22
- Short Name:
- J/MNRAS/440/3462
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from a 1.1-mm imaging survey of the SSA22 field, known for having an overdensity of z=3.1 Lyman{alpha} emitting galaxies (LAEs), taken with the astronomical thermal emission camera (AzTEC) on the Atacama Submillimeter Telescope Experiment (ASTE). We imaged a 950-arcmin2 field down to a 1{sigma} sensitivity of 0.7-1.3mJy/beam to find 125 submillimetre galaxies (SMGs) with a signal-to-noise ratio >=3.5. Counterpart identification using radio and near/mid-infrared data was performed and one or more counterpart candidates were found for 59 SMGs. Photometric redshifts based on optical to near-infrared images were evaluated for 45 of these SMGs with Spitzer/IRAC data and the median value is found to be z=2.4. By combining these estimations with estimates from the literature, we determined that 10 SMGs might lie within the large-scale structure at z=3.1. The two-point angular cross-correlation function between LAEs and SMGs indicates that the positions of the SMGs are correlated with the z=3.1 protocluster. These results suggest that the SMGs were formed and evolved selectively in the high dense environment of the high-redshift Universe. This picture is consistent with the predictions of the standard model of hierarchical structure formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/415/3831
- Title:
- AzTEC/ASTE source catalogue
- Short Name:
- J/MNRAS/415/3831
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 0.72deg^2^ contiguous 1.1-mm survey in the central area of the Cosmological Evolution Survey field carried out to a 1{sigma}~1.26mJy/beam depth with the AzTEC camera mounted on the 10-m Atacama Submillimeter Telescope Experiment. We have uncovered 189 candidate sources at a signal-to-noise ratio (S/N)>=3.5, out of which 129, with S/N>=4, can be considered to have little chance of being spurious (<~2 per cent). We present the number counts derived with this survey, which show a significant excess of sources when compared to the number counts derived from the ~0.5deg^2^ area sampled at similar depths in the Submillimetre Common-User Bolometer Array (SCUBA) HAlf Degree Extragalactic Survey (SHADES).
