- ID:
- ivo://CDS.VizieR/J/AJ/137/4436
- Title:
- Coma cluster VLA survey
- Short Name:
- J/AJ/137/4436
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep 1.4GHz Very Large Array radio continuum observations of two ~0.5{deg}^2^ fields in the Coma cluster of galaxies. The two fields, "Coma 1" and "Coma 3", correspond to the cluster core and southwest infall region and were selected on account of abundant preexisting multiwavelength data. In their most sensitive regions the radio data reach 22uJy rms per 4.4" beam, sufficient to detect (at 5{sigma}) Coma member galaxies with L_1.4GHz_=1.3x10^20^W/Hz. The full catalog of radio detections is presented herein and consists of 1030 sources detected at >=5{sigma}, 628 of which are within the combined Coma 1 and Coma 3 area. We also provide optical identifications of the radio sources using data from the Sloan Digital Sky Survey. The depth of the radio observations allows us to detect active galactic nucleus in cluster elliptical galaxies with M_r_<-20.5 (AB magnitudes), including radio detections for all cluster ellipticals with M_r_<-21.8. At fainter optical magnitudes (-20.5<M_r_~<-19), the radio sources are associated with star-forming galaxies with star formation rates as low as 0.1M_{sun}_/yr.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/499/175
- Title:
- ^12^CO(2-1) map of NGC 2264-C
- Short Name:
- J/A+A/499/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The role played by protostellar feedback in clustered star formation is still a matter of debate. In particular, protostellar outflows have been proposed as a source of turbulence in cluster-forming clumps, which may provide support against global collapse for several free-fall times. Here, we seek to test the above hypothesis in the case of the well-documented NGC 2264-C protocluster, by quantifying the amount of turbulence and support injected in the surrounding medium by protostellar outflows. Using the HERA heterodyne array on the IRAM 30m telescope, we carried out an extensive mapping of NGC 2264-C in the three molecular line transitions ^12^CO(2-1), ^13^CO(2-1), and C^18^O(2-1). We found widespread high-velocity 12 CO emission, testifying to the presence of eleven outflow lobes, closely linked to the compact millimeter continuum sources previously detected in the protocluster. We carried out a detailed analysis of the dynamical parameters of these outflows, including a quantitative evaluation of the overall momentum flux injected in the cluster-forming clump. These dynamical parameters were compared to the gravitational and turbulent properties of the clump. We show that the population of protostellar outflows identified in NGC 2264-C is likely to contribute a significant fraction of the observed turbulence but cannot efficiently support the protocluster against global collapse. Gravity appears to largely dominate the dynamics of the NGC 2264-C clump at the present time ; however it is possible that an increase in the star formation rate during the later evolution of the protocluster will trigger enough outflows to finally halt the contraction of the cloud.
- ID:
- ivo://CDS.VizieR/J/A+A/510/A98
- Title:
- ^12^C^18^O(3-2) map of rho Oph A
- Short Name:
- J/A+A/510/A98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The large submillimetre map of rho Oph A in the ^12^C^18^O(3-2) line, obtained with the APEX 12m telescope, covers 10' in RA by 5' in DE, sampled on a rectangular grid, aligned with the equatorial coordinate system and with regular 20" spacings (548 spectra). An inner ^12^C^18^O(3-2) map, extending over 200" by 200" (462 spectra) is sampled at the Nyqvist frequency.
314. CO maps in Serpens
- ID:
- ivo://CDS.VizieR/J/A+A/519/A27
- Title:
- CO maps in Serpens
- Short Name:
- J/A+A/519/A27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Serpens North cluster is a nearby low mass star forming region which is part of the Gould belt. It contains a range of young stars thought to correspond to two different bursts of star formation and provides the opportunity to study different stages of cluster formation. This work aims to study the molecular gas in the Serpens North cluster to probe the origin of the most recent burst of star formation in Serpens. Transitions of the C^17^O and C^18^O observed with the IRAM 30m telescope and JCMT are used to study the mass and velocity structure of the region while the physical properties of the gas are derived using LTE and non-LTE analyses of the three lowest transitions of C^18^O.
- ID:
- ivo://CDS.VizieR/J/A+A/489/217
- Title:
- CO maps of diffuse Galactic gas towards NRAO 150
- Short Name:
- J/A+A/489/217
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To understand the environment and extended structure of the host galactic gas whose molecular absorption line chemistry, we previously observed along the microscopic line of sight to the blazar/radio-continuum source NRAO 150 (aka B0355+508). We used the IRAM 30m Telescope and Plateau de Bure Interferometer to make two series of images of the host gas: i) 22.5" resolution single-dish maps of ^12^CO J=1-0 and 2-1 emission over a 220" by 220" field; ii) a hybrid (interferometer+singledish) aperture synthesis mosaic of ^12^CO J=1-0 emission at 5.8" resolution over a 90"-diameter region. At 22.5" resolution, the CO J=1-0 emission toward NRAO 150 is 30-100% brighter at some velocities than seen previously with 1' resolution, and there are some modest systematic velocity gradients over the 220" field. Of the five CO components seen in the absorption spectra, the weakest ones are absent in emission toward NRAO 150 but appear more strongly at the edges of the region mapped in emission. The overall spatial variations in the strongly emitting gas have Poisson statistics with rms fluctuations about equal to the mean emission level in the line wings and much of the line cores. The J=2-1/J=1-0 line ratios calculated pixel-by-pixel cluster around 0.7. At 6" resolution, disparity between the absorption and emission profiles of the stronger components has been largely ameliorated. The ^12^CO J=1-0 emission exhibits i) remarkably bright peaks, Tmb=12-13K, even as 4" from NRAO 150; ii) smaller relative levels of spatial fluctuation in the line cores, but a very broad range of possible intensities at every velocity; and iii) striking kinematics whereby the monotonic velocity shifts and supersonically broadened lines in 22.5" spectra are decomposed into much stronger velocity gradients and abrupt velocity reversals of intense but narrow, probably subsonic, line cores. CO components that are observed in absorption at a moderate optical depth (0.5) and are undetected in emission at 1' resolution toward NRAO 150 remain undetected at 6" resolution. This implies that they are not a previously-hidden large-scale molecular component revealed in absorption, but they do highlight the robustness of the chemistry into regions where the density and column density are too low to produce much rotational excitation, even in CO. Bright CO lines around NRAO 150 most probably reflect the variation of a chemical process, i.e. the C+-CO conversion. However, the ultimate cause of the variations of this chemical process in such a limited field of view remains uncertain.
- ID:
- ivo://CDS.VizieR/J/A+A/510/A5
- Title:
- CO(2-1) maps of IRAS 00117+6412
- Short Name:
- J/A+A/510/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our main aim is to study the influence of the initial conditions of a cloud in the intermediate/high-mass star formation process. We observed with the VLA, PdBI, and SMA the centimeter and millimeter continuum, N_2_H^+^ (1-0), and CO (2-1) emission associated with a dusty cloud harboring a nascent cluster with intermediate-mass protostars.
- ID:
- ivo://CDS.VizieR/J/A+A/496/45
- Title:
- CO maps of three lensed submillimetre galaxies
- Short Name:
- J/A+A/496/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Submillimetre galaxies (SMGs) are distant, dusty galaxies undergoing star formation at prodigious rates. Recently there has been major progress in understanding the nature of the bright SMGs (i.e. S_850um_>5mJy). The samples for the fainter SMGs are small and are currently in a phase of being built up through identification studies. We study the molecular gas content in the two SMGs, SMMJ163555 and SMMJ163541, at redshifts z=1.034 and z=3.187 with unlensed submillimetre fluxes of 0.4mJy and 6.0mJy. Both SMGs are gravitationally lensed by the foreground cluster Abell 2218. We used the IRAM Plateau de Bure Interferometer to obtain observations at 3mm of the lines CO(2-1) for SMMJ163555 and CO(3-2) for SMMJ163541. Additionally, we obtained CO(4-3) observations for the candidate z=4.048 SMMJ163556 with an unlensed submillimetre flux of 2.7mJy. Results: The CO(2-1) line was detected for SMMJ163555 at redshift 1.0313 with an integrated line intensity of 1.2+/-0.2Jy.km/s and a line width of 410+/-120km/s. From this a gas mass of 1.6x10^9^M_{sun}_ is derived and a star formation efficiency of 440L_{sun}_/M_{sun}_ estimated. The CO(3-2) line was detected for SMMJ163541 at redshift 3.1824, possibly with a second component at redshift 3.1883, with an integrated line intensity of 1.0+/-0.1Jy.km/s and a line width of 280+/-50km/s. From this a gas mass of 2.2x10^10^M_{sun}_ is derived and a star formation efficiency of 1000L_{sun}_/M_{sun}_ is estimated. For SMMJ163556, the CO(4-3) is undetected within the redshift range 4.035-4.082 down to a sensitivity of 0.15Jy.km/s.
- ID:
- ivo://CDS.VizieR/J/MNRAS/390/819
- Title:
- Combined NVSS-FIRST Galaxies (CoNFIG) sample
- Short Name:
- J/MNRAS/390/819
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The CoNFIG (Combined NVSS-FIRST Galaxies) sample is a new sample of 274 bright radio sources at 1.4GHz. It was defined by selecting all sources with S1.4GHz-1.3Jy from the NRAO Very Large Array (VLA) Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty centimetres (FIRST) survey. New radio observations obtained with the VLA for 31 of the sources are presented. The sample has complete Fanaroff-Riley (FRI)/FRII morphology identification; optical identifications and redshifts are available for 80 and 89 per cent of the sample, respectively, yielding a mean redshift of ~0.71. One of the goals of this survey is to get better definitions of luminosity distributions and source counts of FRI/FRII sources separately, in order to determine the evolution of the luminosity function for each type of source. We present a preliminary analysis, showing that these data are an important step towards examining various evolutionary schemes for these objects and to confirm or correct the dual population unified scheme for radio active galactic nuclei (AGN). Improving our understanding of radio galaxy evolution will give better insight into the role of AGN feedback in galaxy formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/404/1719
- Title:
- Combined NVSS-FIRST galaxies (CoNFIG) sample II
- Short Name:
- J/MNRAS/404/1719
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper focuses on a comparison of the space densities of Fanaroff-Riley type I (FR I) and FR II sources at different epochs, with a particular focus on FR I sources. First, we present the concluding steps in constructing the Combined NVSS-FIRST Galaxies (CoNFIG) catalogue, including new Very Large Array observations, optical identifications and redshift estimates. The final catalogue consists of 859 sources over four samples (CoNFIG-1, -2, -3 and -4 with flux density limits of S1.4GHz=1.3, 0.8, 0.2 and 0.05Jy, respectively). It is 95.7 per cent complete in radio morphology classification and 74.3 per cent of the sources have redshift data. Combining CoNFIG with complementary samples, the distribution and evolution of FR I and FR II sources are investigated. We find that FR I sources undergo mild evolution and that, at the same radio luminosity, FR I and FR II sources show similar space density enhancements in various redshift ranges, possibly implying a common evolution.
- ID:
- ivo://CDS.VizieR/J/ApJ/744/84
- Title:
- Combined sample of radio-loud AGNs at 408MHz
- Short Name:
- J/ApJ/744/84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The work in this paper aims at determining the evolution and possible co-evolution of radio-loud active galactic nuclei (AGNs) and their cores via their radio luminosity functions (i.e., total and core RLFs, respectively). Using a large combined sample of 1063 radio-loud AGNs selected at low radio frequency, we investigate the RLF (radio luminosity function) at 408MHz of steep-spectrum radio sources. Our results support a luminosity-dependent evolution. Using core flux density data of the complete sample 3CRR (Laing et al., 1983, Cat. J/MNRAS/204/151; see also Cat. VIII/1), we investigate the core RLF at 5.0GHz. Based on the combined sample with incomplete core flux data, we also estimate the core RLF using a modified factor of completeness. Both results are consistent and show that the comoving number density of radio cores displays a persistent decline with redshift, implying a negative density evolution. We find that the core RLF is obviously different from the total RLF at the 408 MHz band which is mainly contributed by extended lobes, implying that the cores and extended lobes could not be co-evolving at radio emission.