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11. A CO survey of young planetary nebulae
ID:
ivo://CDS.VizieR/J/ApJS/160/272
Title:
A CO survey of young planetary nebulae
Short Name:
J/ApJS/160/272
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of a sensitive survey of young planetary nebulae in the CO J=2-1 line that significantly increases the available data on warm, dense, molecular gas in the early phases of planetary nebula formation. The observations were made using the IRAM 30m telescope with the 3x3 pixel Heterodyne Receiver Array (HERA). The array provides an effective means of discriminating the CO emission of planetary nebulae in the Galactic plane from contaminating emission of interstellar clouds along the line of sight. A total of 110 planetary nebulae were observed in the survey, and 40 were detected. The results increase the number of young planetary nebulae with known CO emission by approximately a factor of 2. The CO spectra yield radial velocities for the detected nebulae, about half of which have uncertain or no velocity measurements at optical wavelengths. The CO profiles range from parabolic to double-peaked, tracing the evolution of structure in the molecular gas. The line widths are significantly larger than on the asymptotic giant branch, and many of the lines show extended wings, which probably result from the effects on the envelopes of high-velocity jets.
12. ACS Fornax Cluster Survey. I.
ID:
ivo://CDS.VizieR/J/ApJS/169/213
Title:
ACS Fornax Cluster Survey. I.
Short Name:
J/ApJS/169/213
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Fornax Cluster is a conspicuous cluster of galaxies in the southern hemisphere and the second largest collection of early-type galaxies within 20Mpc after the Virgo Cluster. In this paper, we present a brief introduction to the ACS Fornax Cluster Survey - a program to image, in the F475W (g_475_) and F850LP (z_850_) bandpasses, 43 early-type galaxies in Fornax using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. Combined with a companion survey of Virgo, the ACS Virgo Cluster Survey, this represents the most comprehensive imaging survey to date of early-type galaxies in cluster environments in terms of depth, spatial resolution, sample size, and homogeneity. We describe the selection of the program galaxies, their basic properties, and the main science objectives of the survey, which include the measurement of luminosities, colors, and structural parameters for globular clusters associated with these galaxies, an analysis of their isophotal properties and surface brightness profiles, and an accurate calibration of the surface brightness fluctuation distance indicator. Finally, we discuss the data reduction procedures adopted for the survey.
13. ACS Virgo Cluster Survey. I.
ID:
ivo://CDS.VizieR/J/ApJS/153/223
Title:
ACS Virgo Cluster Survey. I.
Short Name:
J/ApJS/153/223
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Virgo Cluster is the dominant mass concentration in the Local Supercluster and the largest collection of elliptical and lenticular galaxies in the nearby universe. In this paper, we present an introduction to the ACS (Advanced Camera for Surveys) Virgo Cluster Survey: a program to image, in the F475W and F850LP bandpasses (~Sloan g and z), 100 early-type galaxies in the Virgo Cluster using the Advanced Camera for Surveys on the Hubble Space Telescope.
14. ACS Virgo Cluster Survey. II.
ID:
ivo://CDS.VizieR/J/ApJS/154/509
Title:
ACS Virgo Cluster Survey. II.
Short Name:
J/ApJS/154/509
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ACS Virgo Cluster Survey is a large program to carry out multicolor imaging of 100 early-type members of the Virgo Cluster using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. Deep F475W and F850LP images (~SDSS g and z) are being used to study the central regions of the program galaxies, their globular cluster systems, and the three-dimensional structure of Virgo itself. In this paper, we describe in detail the data reduction procedures used for the survey, including image registration, drizzling strategies, the computation of weight images, object detection, the identification of globular cluster candidates, and the measurement of their photometric and structural parameters.
15. ACS Virgo Cluster Survey. III. M87
ID:
ivo://CDS.VizieR/J/ApJ/613/279
Title:
ACS Virgo Cluster Survey. III. M87
Short Name:
J/ApJ/613/279
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ACIS instrument on board the Chandra X-Ray Observatory has been used to carry out the first systematic study of low-mass X-ray binaries (LMXBs) in M87, the giant elliptical galaxy near the dynamical center of the Virgo Cluster. These images - with a total exposure time of 154 ks - are the deepest X-ray observations yet obtained of M87. We identify 174 X-ray point sources, of which 150 are likely LMXBs.
16. ACT high significance 148 and 218GHz sources
ID:
ivo://CDS.VizieR/J/MNRAS/439/1556
Title:
ACT high significance 148 and 218GHz sources
Short Name:
J/MNRAS/439/1556
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 191 extragalactic sources detected by the Atacama Cosmology Telescope (ACT) at 148 and/or 218GHz in the 2008 Southern survey. Flux densities span 14 -1700mJy, and we use source spectral indices derived using ACT-only data to divide our sources into two subpopulations: 167 radio galaxies powered by central active galactic nuclei (AGN) and 24 dusty star-forming galaxies (DSFGs). We cross-identify 97 percent of our sources (166 of the AGN and 19 of the DSFGs) with those in currently available catalogues. When combined with flux densities from the Australia Telescope 20GHz survey and follow-up observations with the Australia Telescope Compact Array, the synchrotron-dominated population is seen to exhibit a steepening of the slope of the spectral energy distribution from 20 to 148GHz, with the trend continuing to 218GHz. The ACT dust-dominated source population has a median spectral index, {alpha}_148-218_, of 3.7^+0.62^_-0.86_, and includes both local galaxies and sources with redshift around 6. Dusty sources with no counterpart in existing catalogues likely belong to a recently discovered subpopulation of DSFGs lensed by foreground galaxies or galaxy groups.
17. Active deep learning in large spectros. surveys
ID:
ivo://CDS.VizieR/J/A+A/643/A122
Title:
Active deep learning in large spectros. surveys
Short Name:
J/A+A/643/A122
Date:
21 Oct 2021
Publisher:
CDS
Description:
Current archives of the LAMOST telescope contain millions of pipeline-processed spectra that have probably never been seen by human eyes. Most of the rare objects with interesting physical properties, however, can only be identified by visual analysis of their characteristic spectral features. A proper combination of interactive visualisation with modern machine learning techniques opens new ways to discover such objects. We apply active learning classification methods supported by deep convolutional neural networks to automatically identify complex emission-line shapes in multi-million spectra archives. We used the pool-based uncertainty sampling active learning method driven by a custom-designed deep convolutional neural network with 12 layers. The architecture of the network was inspired by VGGNet, AlexNet, and ZFNet, but it was adapted for operating on one-dimensional feature vectors. The unlabelled pool set is represented by 4.1 million spectra from the LAMOST data release 2 survey. The initial training of the network was performed on a labelled set of about 13000 spectra obtained in the 400{AA} wide region around H{alpha} by the 2m Perek telescope of the Ondrejov observatory, which mostly contains spectra of Be and related early-type stars. The differences between the Ondrejov intermediate-resolution and the LAMOST low-resolution spectrographs were compensated for by Gaussian blurring and wavelength conversion. After several iterations, the network was able to successfully identify emission-line stars with an error smaller than 6.5%. Using the technology of the Virtual Observatory to visualise the results, we discovered 1013 spectra of 948 new candidates of emission-line objects in addition to 664 spectra of 549 objects that are listed in SIMBAD and 2644 spectra of 2291 objects identified in an earlier paper of a Chinese group led by Wen Hou. The most interesting objects with unusual spectral properties are discussed in detail.
18. A Database of Circumstellar OH Masers
ID:
ivo://org.gavo.dc/ohmaser/q/scs
Title:
A Database of Circumstellar OH Masers
Short Name:
engels ohmasers
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").
19. A Database of Circumstellar OH Masers: Interferometric Followups
ID:
ivo://org.gavo.dc/ohmaser/q/mapscs
Title:
A Database of Circumstellar OH Masers: Interferometric Followups
Short Name:
engels oh maps
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").
20. A Database of Circumstellar OH Masers: Monitoring Programs
ID:
ivo://org.gavo.dc/ohmaser/q/monscs
Title:
A Database of Circumstellar OH Masers: Monitoring Programs
Short Name:
engels oh mon
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").

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