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- ID:
- ivo://CDS.VizieR/J/ApJ/720/679
- Title:
- Optical spectroscopy in Cygnus X region
- Short Name:
- J/ApJ/720/679
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new images and photometry of the massive star-forming complex Cygnus X obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope. A combination of IRAC, MIPS, UKIRT Deep Infrared Sky Survey, and Two Micron All Sky Survey data are used to identify and classify young stellar objects (YSOs). Of the 8231 sources detected exhibiting infrared excess in Cygnus X North, 670 are classified as class I and 7249 are classified as class II. Using spectra from the FAST Spectrograph at the Fred L. Whipple Observatory and Hectospec on the MMT, we spectrally typed 536 sources in the Cygnus X complex to identify the massive stars. We find that YSOs tend to be grouped in the neighborhoods of massive B stars (spectral types B0 to B9).
- ID:
- ivo://CDS.VizieR/J/A+A/458/173
- Title:
- Optical spectroscopy of 253 IRAS sources
- Short Name:
- J/A+A/458/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the optical spectral properties of a sample of stars showing far infrared colours similar to those of well-known planetary nebulae. The large majority of them were unidentified sources or poorly known in the literature at the time when this spectroscopic survey started, some 15 years ago. We present low-resolution optical spectroscopy, finding charts and improved astrometric coordinates of a sample of 253 IRAS sources.
- ID:
- ivo://CDS.VizieR/J/AJ/133/186
- Title:
- Optical spectroscopy of 77 luminous AGNs and QSOs
- Short Name:
- J/AJ/133/186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy of a sample of 77 luminous active galactic nuclei (AGNs) and quasars selected on the basis of their mid-infrared colors. Our objects are selected from the Spitzer Extragalactic First Look Survey and the SWIRE XMM-Newton Large-Scale Structure Survey (XMM-LSS) fields, with a typical 24um flux density of 5mJy. The median redshift is 0.6, with a range of ~0.05-4. Only 33% (25 out of 77) of these objects are normal type 1 quasars, with no obscuration. Forty-four percent (34 out of 77) are type 2 objects, with high-ionization, narrow emission lines, and 14% (11 out of 77) are dust-reddened type 1 quasars, showing broad lines but a dust-reddened or unusually weak quasar continuum.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJS/78/239
- Title:
- Orion stars CO-added IRAS fluxes catalog
- Short Name:
- J/ApJS/78/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog of co-added IRAS fluxes for the pre-main-sequence objects in the Herbig-Bell catalog (HBC) is presented. This catalog doubles the number of HBC stars with detected IRAS fluxes and provides improved flux values for the previously known sources. Noise levels are given for all HBC fields in each band, permitting upper limits to be estimated for all undetected sources.
- 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/ApJS/219/20
- Title:
- Outflows and bubbles in Taurus
- Short Name:
- J/ApJS/219/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified outflows and bubbles in the Taurus molecular cloud based on the ~100deg^2^ Five College Radio Astronomy Observatory ^12^CO(1-0) and ^13^CO(1-0) maps and the Spitzer young stellar object catalogs. In the main 44deg^2^ area of Taurus, we found 55 outflows, of which 31 were previously unknown. We also found 37 bubbles in the entire 100deg^2^ area of Taurus, none of which had been found previously. The total kinetic energy of the identified outflows is estimated to be ~3.9x10^45^erg, which is 1% of the cloud turbulent energy. The total kinetic energy of the detected bubbles is estimated to be ~9.2x10^46^erg, which is 29% of the turbulent energy of Taurus. The energy injection rate from the outflows is ~1.3x10^33^erg/s, which is 0.4-2 times the dissipation rate of the cloud turbulence. The energy injection rate from bubbles is ~6.4x10^33^erg/s, which is 2-10 times the turbulent dissipation rate of the cloud. The gravitational binding energy of the cloud is ~1.5x10^48^erg, that is, 385 and 16 times the energy of outflows and bubbles, respectively. We conclude that neither outflows nor bubbles can provide sufficient energy to balance the overall gravitational binding energy and the turbulent energy of Taurus. However, in the current epoch, stellar feedback is sufficient to maintain the observed turbulence in Taurus.
- ID:
- ivo://CDS.VizieR/J/MNRAS/469/4565
- Title:
- Overdensities of submm-galaxies around AGNs
- Short Name:
- J/MNRAS/469/4565
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate extremely luminous dusty galaxies in the environments around Wide-field Infrared Survey Explorer (WISE)-selected hot dust-obscured galaxies (Hot DOGs) and WISE/radio-selected active galactic nuclei (AGNs) at average redshifts of z=2.7 and 1.7, respectively. Previous observations have detected overdensities of companion submillimetre-selected sources around 10 Hot DOGs and 30 WISE/radio AGNs, with overdensities of ~2-3 and ~5-6, respectively. We find that the space densities in both samples to be overdense compared to normal star-forming galaxies and submillimetre galaxies (SMGs) in the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) Cosmology Legacy Survey (S2CLS). Both samples of companion sources have consistent mid-infrared (mid-IR) colours and mid-IR to submm ratios as SMGs. The brighter population around WISE/radio AGNs could be responsible for the higher overdensity reported. We also find that the star formation rate densities are higher than the field, but consistent with clusters of dusty galaxies. WISE-selected AGNs appear to be good signposts for protoclusters at high redshift on arcmin scales. The results reported here provide an upper limit to the strength of angular clustering using the two-point correlation function. Monte Carlo simulations show no angular correlation, which could indicate protoclusters on scales larger than the SCUBA-2 1.5-arcmin scale maps.
- ID:
- ivo://CDS.VizieR/J/ApJ/805/121
- Title:
- Overdensities of 0<z<3 COSMOS galaxies
- Short Name:
- J/ApJ/805/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is well-known that a galaxy's environment has a fundamental influence in shaping its properties. We study the environmental effects on galaxy evolution, with an emphasis on the environment defined as the local number density of galaxies. The density field is estimated with different estimators (weighted adaptive kernel smoothing, 10th and 5th nearest neighbors, Voronoi and Delaunay tessellation) for a K_s_<24 sample of ~190000 galaxies in the COSMOS field at 0.1<z<3.1. The performance of each estimator is evaluated with extensive simulations. We show that overall there is a good agreement between the estimated density fields using different methods over ~2dex in overdensity values. However, our simulations show that adaptive kernel and Voronoi tessellation outperform other methods. Using the Voronoi tessellation method, we assign surface densities to a mass complete sample of quiescent and star-forming galaxies out to z~3. We show that at a fixed stellar mass, the median color of quiescent galaxies does not depend on their host environment out to z~3. We find that the number and stellar mass density of massive (>10^11^M_{sun}_) star-forming galaxies have not significantly changed since z~3, regardless of their environment. However, for massive quiescent systems at lower redshifts (z<~1.3), we find a significant evolution in the number and stellar mass densities in denser environments compared to lower density regions. Our results suggest that the relation between stellar mass and local density is more fundamental than the color-density relation and that environment plays a significant role in quenching star-formation activity in galaxies at z<~1.
