- ID:
- ivo://CDS.VizieR/J/A+A/564/A65
- Title:
- Cold gas properties of Herschel Reference Survey
- Short Name:
- J/A+A/564/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new ^12^CO(1-0) observations of 59 late-type galaxies belonging to the Herschel Reference Survey (HRS), a complete K-band-selected, volume-limited (15<=D<=25Mpc) sample of nearby galaxies spanning a wide range in morphological type and luminosity. We studied different recipes to correct single-beam observations of nearby galaxies of different sizes and inclinations for aperture effects. This was done by comparing single-beam and multiple-beam observations along the major axis, which were corrected for aperture effects using different empirical or analytical prescriptions, to integrated maps of several nearby galaxies, including edge-on systems observed by different surveys. The resulting recipe is an analytical function determined by assuming that late-type galaxies are 3D exponentially declining discs with a characteristic scale length r_CO_=0.2r_24.5_, where r_24.5_ is the optical, g- (or B-) band isophotal radius at the 24.5mag/arcsec^2^ (25mag/arcsec^2^), as well as a scale height z_CO_=1/100r_24.5_. Our new CO data are then combined with those available in the literature to produce the most updated catalogue of CO observations for the HRS, now including 225 out of the 322 galaxies of the complete sample. The 3D exponential disc integration is applied to all the galaxies of the sample to measure their total CO fluxes, which are later transformed into molecular gas masses using a constant and a luminosity-dependent X_CO_ conversion factor. We also collect HI data for 315 HRS galaxies from the literature and present it in a homogenised form.
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- ID:
- ivo://CDS.VizieR/J/A+A/550/A41
- Title:
- CO line survey in 0.2<z<1 of galaxies
- Short Name:
- J/A+A/550/A41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- After new observations of 39 galaxies at z=0.6-1.0 obtained at the IRAM 30m telescope, we present our full CO line survey covering the redshift range 0.2<z<1. Our aim is to determine the driving factors accounting for the steep decline in the star formation rate during this epoch. We study both the gas fraction, defined as Mgas/(Mgas+Mstar), and the star formation efficiency (SFE) defined by the ratio between far-infrared luminosity and molecular gas mass (L_FIR_/M(H_2_), i.e. a measure for the inverse of the gas depletion time. The sources are selected to be ultra-luminous infrared galaxies (ULIRGs), with L_FIR_ greater than 10^12^L_{sun}_, and experiencing starbursts. When we adopt a standard ULIRG CO-to-H_2_ conversion factor, their molecular gas depletion time is less than 100Myr. Our full survey has now filled the gap of CO observations in the 0.2<z<1 range covering almost half of cosmic history. The detection rate in the 0.6<z<1 interval is 38% (15 galaxies out of 39), compared to 60% for the 0.2<z<0.6 interval. The average CO luminosity is L'_CO_=1.8x10^10^K.km/s.pc^2^, corresponding to an average H_2_ mass of 1.45x10^10^M_{sun}_. From observation of 7 galaxies in both CO(2-1) and CO(4-3), a high gas excitation has been derived; together with the dust mass estimation, this supports the choice of our low ULIRG conversion factor between CO luminosity and H_2_ for our sample sources. We find that both the gas fraction and the SFE significantly increase with redshift, by factors of 3+/-1 from z=0 to 1, and therefore both quantities play an important role and complement each other in cosmic star formation evolution.
- 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/ApJ/867/165
- Title:
- CO molecular clumps in Henize 2-10 dwarf galaxy
- Short Name:
- J/ApJ/867/165
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Atacama Large Millimeter/Submillimeter Array CO(3-2) observations at 0.3" resolution of He 2-10, a starburst dwarf galaxy and possible high-z galaxy analog. The warm dense gas traced by CO(3-2) is found in clumpy filaments that are kinematically and spatially distinct. The filaments have no preferred orientation or direction; this may indicate that the galaxy is not evolving into a disk galaxy. Filaments appear to be feeding the active starburst; the velocity field in one filament suggests acceleration onto an embedded star cluster. The relative strengths of CO(3-2) and radio continuum vary strongly on decaparsec scales in the starburst. There is no CO(3-2) clump coincident with the nonthermal radio source that has been suggested to be an AGN, nor unusual kinematics. The kinematics of the molecular gas show significant activity that is apparently unrelated to the current starburst. The longest filament, east of the starburst, has a pronounced shear of FWHM ~40km/s across its ~50pc width over its entire ~0.5kpc length. The cause of the shear is not clear. This filament is close in projection to a "dynamically distinct" CO feature previously seen in CO(1-0). The most complex region and the most highly disturbed gas velocities are in a region 200pc south of the starburst. The CO(3-2) emission there reveals a molecular outflow, of line width FWZI~120-140km/s, requiring an energy >~10^53^erg/s. There is at present no candidate for the driving source of this outflow.
- ID:
- ivo://CDS.VizieR/J/ApJS/166/526
- Title:
- Compact extragalactic radio sources
- Short Name:
- J/ApJS/166/526
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Very Large Array to search for compact milliarcsecond-size radio sources near methanol masers in high-mass star-forming regions. Such sources are required for very long baseline Interferometry phase-referencing observations. We conducted pointed observations of 234 compact sources found in the NVSS survey and find 92 sources with unresolved components and synchrotron spectral indexes. These sources are likely the cores of AGNs and, thus, are good candidates for astrometric calibrators.
- ID:
- ivo://CDS.VizieR/J/MNRAS/268/602
- Title:
- Compact radio cores in radio galaxies.
- Short Name:
- J/MNRAS/268/602
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains compact core fluxes for a list of 175 southern radio galaxies, measured with the Parkes-Tidbinbilla Interferometer (PTI, Norris et al. 1988ApJS...67...85N) on a single 275 km baseline at 2.3 GHz and 8.4 GHz. The sample consists of large angular size ( > 0.5 arcmin) steep spectrum sources from Jones & McAdam (1992ApJS...80..137J) observed to determine the fraction of flux contained in compact (VLBI-scale) cores. Of the 172 sources observed at 2.3 GHz (100 milliarcsec fringe spacing), 63 had cores detected and upper limits were determined for the remaining 109. Of the 88 sources observed at 8.4 GHz (30 milliarcsec fringe spacing), 38 had cores detected and 50 have upper limits. A comparison of the detections and upper limits at the two frequencies shows that the cores have flat or inverted spectra. The core fluxes quoted here may vary by around 20 % if there is structure on the scale of the fringe spacing and the cores are probably intrinsically variable.
- ID:
- ivo://CDS.VizieR/J/ApJ/511/612
- Title:
- Comparison of Radio-loud and Quiet Quasars
- Short Name:
- J/ApJ/511/612
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have made radio observations of 87 optically selected quasars at 5 GHz with the VLA in order to measure the radio power for these objects and hence determine how the fraction of radio-loud quasars varies with redshift and optical luminosity. The sample has been selected from the recently completed Edinburgh Quasar Survey and covers a redshift range of 0.3{<=}z{<=}1.5 and an optical absolute magnitude range of (-26.5){<=}M_B_{<=}(-23.5) (h=1/2, q_o_=1/2). We have also matched other existing surveys with the Faint Images of the Radio Sky at Twenty Centimeters and NRAO VLA Sky Survey radio catalogs and combined these data so that the optical luminosity-redshift plane is now far better sampled than before. We have fitted a model to the probability of a quasar being radio-loud as a function of absolute magnitude and redshift, and from this model we infer the radio-loud and radio-quiet optical luminosity functions. The radio-loud optical luminosity function is featureless and flatter than the radio-quiet one. It evolves at a marginally slower rate if quasars evolve by density evolution, but the difference in the rate of evolutions of the two different classes is much less than was previously thought.
- ID:
- ivo://CDS.VizieR/VIII/56
- Title:
- Compendium of Radio Measurements of Bright Galaxies
- Short Name:
- VIII/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains all radio measurements of optically bright 'normal' galaxies available up until publication of this compendium in 1975. The compendium was originally intended to simplify statistical analysis of radio properties of these normal galaxies. No data processing was carried out (except to bring the data into a consistent format) and no identification was attempted. These data were originally published as Haynes R.F., Huchtmeier W.K.H., Siegman B., and Wright A.E., CSIRO Publication, 1975. The electronic version of this catalog has made small changes to the original version in an attempt to better identify positions with their source names. Where there was no entry on a line for the source name or position in the published version, data from the previous line was repeated.
- ID:
- ivo://CDS.VizieR/J/MNRAS/430/3086
- Title:
- CoNFIG AGN sample
- Short Name:
- J/MNRAS/430/3086
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The goal of this work is to determine the nature of the relation between morphology and accretion mode in radio galaxies, including environmental parameters. The CoNFIG extended catalogue (improved by new K_S_-band identifications and estimated redshifts from UKIRT Infrared Deep Sky Survey (UKIDSS), and spectral index measurements from new GMRT observations) is used to select a sub-sample of 206 radio galaxies with z<=0.3 over a wide range of radio luminosity, which are morphology-classified using the Fanaroff-Riley (FR) classification of extended radio sources. For each galaxy, spectroscopic data are retrieved to determine the high/low excitation status of the source, related to its accretion mode. Environmental factors, such as the host galaxy luminosity and a richness factor, are also computed, generally using the Sloan Digital Sky Survey data.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A128
- Title:
- Continuum and CO maps of 3C 293
- Short Name:
- J/A+A/564/A128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Powerful radio galaxies show evidence of ongoing active galactic nuclei (AGN) feedback, mainly in the form of fast, massive outflows. But it is not clear how these outflows affect the star formation of their hosts. We investigate the different manifestations of AGN feedback in the evolved, powerful radio source 3C 293 and their impact on the molecular gas of its host galaxy, which harbors young star-forming regions and fast outflows of H i and ionized gas. We study the distribution and kinematics of the molecular gas of 3C 293 using high spatial resolution observations of the ^12^CO(1-0) and ^12^CO(2-1) lines, and the 3mm and 1 continuum taken with the IRAM Plateau de Bure interferometer. We mapped the molecular gas of 3C 293 and compared it with the dust and star-formation images of the host. We searched for signatures of outflow motions in the CO kinematics, and re-examined the evidence of outflowing gas in the HI spectra. We also derived the star formation rate (SFR) and star formation efficiency (SFE) of the host with all available SFR tracers from the literature, and compared them with the SFE of young and evolved radio galaxies and normal star-forming galaxies. The ^12^CO(1-0) emission line shows that the molecular gas in 3C 293 is distributed along a massive (M(H_2_)~2.2x10^10^M_{sun}_) ~24" (21kpc) diameter warped disk, that rotates around the AGN. Our data show that the dust and the star formation are clearly associated with the CO disk. The ^12^CO(2-1) emission is located in the inner 7kpc (diameter) region around the AGN, coincident with the inner part of the ^12^CO(1-0) disk. Both the ^12^CO(1-0) and ^12^CO(2-1) spectra reveal the presence of an absorber against the central regions of 3C 293 that is associated with the disk. We do not detect any fast (500km/s) outflow motions in the cold molecular gas. The host of 3C 293 shows an SFE consistent with the Kennicutt-Schmidt law of normal galaxies and young radio galaxies, and it is 10-50 times higher than the SFE estimated with the 7.7um PAH emission of evolved radio galaxies. Our results suggest that the apparently low SFE of evolved radio galaxies may be caused by an underestimation of the SFR and/or an overestimation of the molecular gas densities in these sources. The molecular gas of 3C 293, while not incompatible with a mild AGN-triggered flow, does not reach the high velocities (500km/s) observed in the HI spectrum. We find no signatures of AGN feedback in the molecular gas of 3C 293.
