- 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.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/2439
- Title:
- Coma Treasury Survey. Structural parameters
- Short Name:
- J/MNRAS/411/2439
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of structural parameters for 8814 galaxies in the 25 fields of the Hubble Space Telescope/ACS Coma Treasury Survey. Parameters from Sersic fits to the two-dimensional surface brightness distributions are given for all galaxies from our published Coma photometric catalogue with mean effective surface brightness brighter than 26.0mag/arcsec^2^ and brighter than 24.5mag (equivalent to absolute magnitude -10.5), as given by the fits, all in F814W(AB). The sample comprises a mixture of Coma members and background objects; 424 galaxies have redshifts and of these 163 are confirmed members. The fits were carried out using both the GIM2D and GALFIT codes.
- 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/ApJ/675/1459
- Title:
- Compact Binary Coalescence Galaxy Catalog
- Short Name:
- J/ApJ/675/1459
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An up-to-date catalog of nearby galaxies considered to be hosts of binary compact objects is provided, with complete information about sky position, distance, extinction-corrected blue luminosity, and error estimates. With our current understanding of binary evolution, rates of formation and coalescence for binary compact objects scale with massive-star formation, and hence the (extinction-corrected) blue luminosity of host galaxies. Coalescence events in binary compact objects are among the most promising gravitational-wave sources for ground-based gravitational-wave detectors such as LIGO. Our catalog and associated error estimates are important for the interpretation of analyses carried out for LIGO, in constraining the rates of compact binary coalescence, given an astrophysical population model for the sources considered.
- ID:
- ivo://CDS.VizieR/J/A+A/578/A134
- Title:
- Compact early-type galaxies in SDSS
- Short Name:
- J/A+A/578/A134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Passive galaxies at high redshift are much smaller than equally massive early types today. If this size evolution is caused by stochastic merging processes, then a small fraction of the compact galaxies should persist until today. Up to now it has not been possible to systematically identify the existence of such objects in Sloan Digital Sky Survey (SDSS). We aim at finding potential survivors of these compact galaxies in SDSS, as targets for more detailed follow-up observations. From the virial theorem, it is expected that for a given mass, compact galaxies have stellar velocity dispersion higher than the mean owing to their smaller sizes. Therefore velocity dispersion, coupled with size (or mass), is an appropriate method of selecting relics, independent of the stellar population properties. Based on these considerations, we designed a set of criteria the use the distribution of early-type galaxies from SDSS on the log_10_(R_0_)-log_10_({sigma}_0_) plane to find the most extreme objects on it. We thus selected compact massive galaxy candidates by restricting them to high velocity dispersions {sigma}_0_>323.2km/s and small sizes R_0_<2.18kpc. We find 76 galaxies at 0.05<z<0.2, which have properties that are similar to the typical quiescent galaxies at high redshift. We discuss how these galaxies relate to average present-day early-type galaxies. We study how well these galaxies fit on well-known local universe relations of early-type galaxies, such as the fundamental plane, the red sequence, or mass-size relations. As expected from the selection criteria, the candidates are located in an extreme corner of the mass-size plane. However, they do not extend as deeply into the so-called zone of exclusion as some of the red nuggets found at high redshift, since they are a factor 2-3 less massive on a given intrinsic scale size. Several of our candidates are close to the size resolution limit of SDSS, but are not so small that they are classified as point sources. We find that our candidates are systematically offset on a scaling relation compared to the average early-type galaxies, but still within the general range of other early-type galaxies. Furthermore, our candidates are similar to the mass-size range expected for passive evolution of the red nuggets from their high redshift to the present. The 76 selected candidates form an appropriate set of objects for further follow-up observations. They do not constitute a separate population of peculiar galaxies, but form the extreme tail of a continuous distribution of early-type galaxies. We argue that selecting a high-velocity dispersion is the best way to find analogues of compact high redshift galaxies in the local universe.
- 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/441/224
- Title:
- Compact FIR-bright sources in M33
- Short Name:
- J/MNRAS/441/224
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multiwavelength study of a sample of far-infrared (FIR) sources detected on the Herschel broad-band maps of the nearby galaxy M33. We perform source photometry on the FIR maps as well as mid-infrared (MIR), H{alpha}, far-ultraviolet and integrated Hi and CO line emission maps. By fitting MIR/FIR dust emission spectra, the source dust masses, temperatures and luminosities are inferred. The sources are classified based on their H{alpha} morphology (sub-structured versus not-substructured) and on whether they have a significant CO detection (S/N>3{sigma}). We find that the sources have dust masses in the range 10^2^-10^4^M_{sun}_ and that they present significant differences in their inferred dust/star formation/gas parameters depending on their H{alpha} morphology and CO detection classification. The results suggests differences in the evolutionary states or in the number of embedded HII regions between the sub-samples. The source background-subtracted dust emission seems to be predominantly powered by local star formation, as indicated by a strong correlation between the dust luminosity and the dust-corrected H{alpha} luminosity and the fact that the extrapolated young stellar luminosity is high enough to account for the observed dust emission. Finally, we do not find a strong correlation between the dust-corrected H{alpha} luminosity and the dust mass of the sources, consistent with previous results on the breakdown of simple scaling relations at sub-kpc scales. However, the scatter in the relation is significantly reduced by correcting the H{alpha} luminosity for the age of the young stellar populations in the star-forming regions.
- ID:
- ivo://CDS.VizieR/J/ApJ/720/723
- Title:
- Compact galaxies in the local universe
- Short Name:
- J/ApJ/720/723
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We set out to test the claim that the recently identified population of compact, massive, and quiescent galaxies at z~2.3 must undergo significant size evolution to match the properties of galaxies found in the local universe. Using data from the Sloan Digital Sky Survey (SDSS; Data Release 7), we have conducted a search for local red sequence galaxies with sizes and masses comparable to those found at z~2.3. The SDSS spectroscopic target selection algorithm excludes high surface brightness objects; we show that this makes incompleteness a concern for such massive, compact galaxies, particularly for low redshifts (z<~0.05). We have identified 63 M_*_>10^10.7^M_{sun}_ (~5x10^10^M_{sun}_) red sequence galaxies at 0.066<z_spec_<0.12 which are smaller than the median size-mass relation by a factor of 2 or more. Consistent with expectations from the virial theorem, the median offset from the mass-velocity dispersion relation for these galaxies is 0.12 dex. We do not, however, find any galaxies with sizes and masses comparable to those observed at z~2.3, implying a decrease in the comoving number density of these galaxies, at fixed size and mass, by a factor of >~5000. This result cannot be explained by incompleteness: in the 0.066<z<0.12 interval, we estimate that the SDSS spectroscopic sample should typically be >~75% complete for galaxies with the sizes and masses seen at high redshift, although for the very smallest galaxies it may be as low as ~20%. In order to confirm that the absence of such compact massive galaxies in SDSS is not produced by spectroscopic selection effects, we have also looked for such galaxies in the basic SDSS photometric catalog, using photometric redshifts. While we do find signs of a slight bias against massive, compact galaxies, this analysis suggests that the SDSS spectroscopic sample is missing at most a few objects in the regime we consider.
- ID:
- ivo://CDS.VizieR/J/A+A/391/35
- Title:
- Compact Groups in the UZC galaxy sample
- Short Name:
- J/A+A/391/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Applying an automatic neighbour search algorithm to the 3D UZC galaxy catalogue (Falco et al., 1999, Cat. <J/PASP/111/438>) we have identified 291 compact groups (CGs) with radial velocity between 1000 and 10000km/s. The sample is analysed to investigate whether Triplets display kinematical and morphological characteristics similar to higher order CGs (Multiplets). It is found that Triplets constitute low velocity dispersion structures, have a gas-rich galaxy population and are typically retrieved in sparse environments. Conversely Multiplets show higher velocity dispersion, include few gas-rich members and are generally embedded structures. Evidence hence emerges indicating that Triplets and Multiplets, though sharing a common scale, correspond to different galaxy systems. Triplets are typically field structures whilst Multiplets are mainly subclumps (either temporarily projected or collapsing) within larger structures. Simulations show that selection effects can only partially account for differences, but significant contamination of Triplets by field galaxy interlopers could eventually induce the observed dependences on multiplicity.
- ID:
- ivo://CDS.VizieR/VII/89B
- Title:
- Compact groups of compact galaxies
- Short Name:
- VII/89B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a compilation of ten published lists of compact groups of compact galaxies found on the Palomar Sky Survey red charts. The catalog contains 377 groups of compact galaxies and includes identifications, equatorial coordinates, numbers of constituent galaxies, magnitudes of the brightest member, sizes of the groups as a whole, and coefficients of relative compactness.
