- ID:
- ivo://CDS.VizieR/J/ApJ/663/218
- Title:
- Optical Spectroscopy of WIYN Hydra FLS sources
- Short Name:
- J/ApJ/663/218
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectroscopic survey of 24um and 1.4GHz sources, detected in the Spitzer extragalactic First Look Survey (FLS), using the multifiber spectrograph, Hydra, on the WIYN telescope. We have obtained spectra for 772 sources, with flux densities above 0.15mJy in the infrared and 0.09mJy in the radio. The redshifts measured in this survey are mostly in the range 0<z<0.4, with a distribution peaking at z~0.2.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AN/340/437
- Title:
- Optical variability of blazars
- Short Name:
- J/AN/340/437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The analysis of blazars' parameters from BZCAT leads to a conclusion that they do not have the same properties. The preliminary criterion to include an object in the catalog was the strong radio emission; however, two type of radio sources were selected: BL Lacertae (BLL) objects and Flat Spectrum Radio Quasars (FSRQ). As a number of properties are typical of blazars (strong radio emission, optical variability, continuum optical spectra, polarization, high luminosity, etc.), using the optical data, we investigate them to clarify which property plays the most significant role in their classification as blazars. We found that 60% of blazars have optical variability. We use a technique developed based on POSS1 and POSS2 photometry and group the variability into extreme, strong, medium, and low classes. In the optical range, 51 blazars have powerful variability (extreme variables), and 126 are high variables. In addition, 63% of blazars have detected radiation in X-ray and 28% have detected radiation in gamma rays. We give the average statistical characteristics of blazars based on our analysis and calculations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/L107
- Title:
- Outbursts of GX339-4 at 5.5 and 9.0GHz fluxes
- Short Name:
- J/MNRAS/431/L107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galactic black hole binaries produce powerful outflows which emit over almost the entire electromagnetic spectrum. Here, we report the first detection with the Herschel observatory of a variable far-infrared source associated with the compact jets of the black hole transient GX 339-4 during the decay of its recent 2010-2011 outburst, after the transition to the hard state. We also outline the results of very sensitive radio observations conducted with the Australia Telescope Compact Array, along with a series of near-infrared, optical (OIR) and X-ray observations, allowing for the first time the re-ignition of the compact jets to be observed over a wide range of wavelengths. The compact jets first turn on at radio frequencies with an optically thin spectrum that later evolves to an optically thick synchrotron emission. An OIR reflare is observed about 10d after the onset of radio and hard X-ray emission, likely reflecting the necessary time to build up enough density, as well as to have acceleration (e.g. through shocks) along an extended region in the jets. The Herschel measurements are consistent with an extrapolation of the radio inverted power-law spectrum, but they highlight a more complex radio to OIR spectral energy distribution for the jets.
- ID:
- ivo://CDS.VizieR/J/A+A/399/1083
- Title:
- Outer Galaxy IRAS sources and 12CO emission
- Short Name:
- J/A+A/399/1083
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examined all of the IRAS sources within the Five College Radio Astronomy Observatory (FCRAO) Outer Galaxy Survey (OGS) region for associated ^12^CO emission (as accounted for in the Brunt, Kerton, and Pomerleau (2003, in press) catalogue of ^12^CO emission in the OGS). Table 1 provides a ranked listing of IRAS-CO associations and Table 2 provides a listing of those IRAS sources with no CO associations. In order to rank the various IRAS-CO associations we examined the association of random lines of sight with CO emission in the OGS. The resulting expectation numbers are provided to the reader in Table A1.
- ID:
- ivo://CDS.VizieR/J/AJ/92/787
- Title:
- Outer galaxy VLA survey
- Short Name:
- J/AJ/92/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VLA has been used to make a "snapshot" survey of all radio continuum sources stronger than 0.3Jy at 21cm, smaller than 2arcmin, and in the area in the sky defined by l=93{deg} to 163{deg}, b=-4{deg} to +4{deg}. These objects were observed at 6 cm with a resolution of 4 arcsec and a sensitivity of 1mJy. A second set of observations were carried out to determine the spectral indices of all objects not resolved in the 6 cm survey. These objects were observed at a wavelength of 2cm with resolution and sensitivity similar to the 6cm survey. The purpose of this study was to identify objects within the disk of the outer parts of our galaxy. It is shown that the current lists of identified H II regions in this area are better than ~70% complete for H II regions in the Perseus arm or closer. The only supernova remnants remaining to be discovered in this field are either extremely young, and therefore possibly radio quiet, or they are among those objects too extended to be observed at the VLA in this survey (i.e., greater than 2arcmin in diameter).
- ID:
- ivo://CDS.VizieR/J/ApJ/899/55
- Title:
- Parameters of protoplanetary disks in 5 SFRs
- Short Name:
- J/ApJ/899/55
- Date:
- 14 Mar 2022 07:11:43
- Publisher:
- CDS
- Description:
- Spatial correlations among protoplanetary disk orientations carry unique information on physics of multiple-star formation processes. We select five nearby star-forming regions that comprise a number of protoplanetary disks with spatially resolved images with ALMA and Hubble Space Telescope, and we search for the mutual alignment of the disk axes. Specifically, we apply the Kuiper test to examine the statistical uniformity of the position angle (PA: the angle of the major axis of the projected disk ellipse measured counterclockwise from the north) distribution. The disks located in the star-forming regions, except the Lupus clouds, do not show any signature of the alignment, supporting the random orientation. Rotational axes of 16 disks with spectroscopic measurement of PA in the LupusIII cloud, a subregion of the Lupus field, however, exhibit a weak and possible departure from the random distribution at a 2{sigma} level, and the inclination angles of the 16 disks are not uniform as well. Furthermore, the mean direction of the disk PAs in the LupusIII cloud is parallel to the direction of its filament structure and approximately perpendicular to the magnetic field direction. We also confirm the robustness of the estimated PAs in the Lupus clouds by comparing the different observations and estimators based on three different methods, including sparse modeling. The absence of the significant alignment of the disk orientation is consistent with the turbulent origin of the disk angular momentum. Further observations are required to confirm/falsify the possible disk alignment in the Lupus III cloud.
- ID:
- ivo://CDS.VizieR/J/ApJ/801/L26
- Title:
- Parameters of radio sources near Sgr A*
- Short Name:
- J/ApJ/801/L26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radio images within 30" of Sgr A* based on recent VLA observations at 34 GHz with 7.8 {mu}Jy sensitivity and resolution of ~88x46 mas. We report 44 partially resolved compact sources clustered in two regions in the E arm of ionized gas that orbits Sgr A*. These sources have size scales ranging between ~50 and 200 mas (400-1600 AUs), and a bow-shock appearance facing the direction of Sgr A*. Unlike the bow-shock sources previously identified in the near-IR but associated with massive stars, these 34 GHz sources do not appear to have near-IR counterparts at 3.8 {mu}m. We interpret these sources as a candidate population of photoevaporative protoplanetary disks (proplyds) that are associated with newly formed low mass stars with mass loss rates ~10^-7^-10^-6^ M_{sun}_/yr and are located at the edge of a molecular cloud outlined by ionized gas. The disks are externally illuminated by strong Lyman continuum radiation from the ~100 OB and WR massive stars distributed within 10" of Sgr A*. The presence of proplyds implies current in situ star formation activity near Sgr A* and opens a window for the first time to study low mass star, planetary, and brown dwarf formations near a supermassive black hole. The video abstract was created from a WorldWide Telescope tour file, which is available for download. Viewing the file requires a Windows PC with the WorldWide Telescope desktop client available at worldwidetelescope.org.
- ID:
- ivo://CDS.VizieR/VIII/34
- Title:
- Parkes Half-Jansky Flat-Spectrum Sample
- Short Name:
- VIII/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new sample of Parkes half-Jansky flat-spectrum radio sources having made a particular effort to find any previously unidentified sources. The sample contains 323 sources selected according to a flux limit of 0.5 Jy at 2.7 GHz, a spectral index measured between 2.7 and 5.0 GHz of {alpha}(2.7/5.0) > -0.5, where S(f) is proportional to f^alpha^, Galactic latitude |b| > 20{deg} and -45{deg} < Declination(B1950) < +10{deg}. The sample was selected from a region 3.90 steradians in area. We have obtained accurate radio positions for all the unresolved sources in this sample and combined these with accurate optical positions from digitised photographic sky survey data to check all the optical identifications. We report new identifications based on R- and Kn-band imaging and new spectroscopic measurements of many of the sources. We present a catalogue of the 323 sources of which 321 now have identified optical counterparts and 277 have measured spectral redshifts.
- ID:
- ivo://CDS.VizieR/VIII/8A
- Title:
- Parkes High-Latitude H I Survey
- Short Name:
- VIII/8A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This survey consists of HI 21-cm spectra covering the southern sky with absolute galactic latitude |b|>=10 degrees and declination dec<=-30 degrees. The observations were made with the Parkes Radio Observatory (CSIRO) 60-foot telescope. The receiver back end was the Parkes 64-channel spectrometer. The velocity resolution was 7km/s (33kHz) and the beamwidth (HPBW) was 48arcmin. Drift scans at constant declination were used with continuous integration in right ascension for -80<=declination<=-30 degrees. For declination<-80 degrees a grid of positions spaced 1 degree apart in declination and one beam-width apart in right ascension were observed. The survey was made in two parts. Part 1 included b>=-25 degrees, |b|>=10 degrees and declination dec<=-30 degrees. Part 2 included b<=-25 degrees and dec<=-30 degrees. The scans in Part 1 were spaced at 1 degree intervals in declination and the velocity coverage was from -148 to +300km/s. The scans in Part 2 were spaced at 2 degrees and the velocity coverage was from -230 to +218km/s. Each spectrum or record consists of a header followed by 64 antenna temperatures. The header contains the galactic longitude, galactic latitude, right ascension, declination, central velocity (LSR), and quality factor. The catalog contains a total of 9891 spectra.
- ID:
- ivo://CDS.VizieR/J/MNRAS/335/275
- Title:
- Parkes Multi-Beam Pulsar Survey new PSR
- Short Name:
- J/MNRAS/335/275
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Parkes Multibeam Pulsar Survey is a sensitive survey of a strip of the Galactic plane with |b|<5{deg} and 260{deg}<l<50{deg} at 1374MHz. Here we report the discovery of 120 new pulsars and subsequent timing observations, primarily using the 76-m Lovell radio telescope at Jodrell Bank. The main features of the sample of 370 published pulsars discovered during the multibeam survey are described. Furthermore, we highlight two pulsars: PSR J1734-3333, a young pulsar with the second highest surface magnetic field strength among the known radio pulsars, B_S_=5.4x10^13^G, and PSR J1830-1135, he second slowest radio pulsar known, with a 6-s period.
