- ID:
- ivo://CDS.VizieR/J/ApJS/122/221
- Title:
- A mid-IR survey of Proto-PNs Candidates
- Short Name:
- J/ApJS/122/221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the data from a mid-infrared (MIR) imaging survey of 66 proto-planetary nebula candidates using two MIR cameras (MIRAC2 and Berkcam) at the NASA Infrared Telescope Facility and the United Kingdom Infrared Telescope. The goal of this survey is to determine the size, flux, and morphology of the MIR emission regions, which sample the inner regions of the circumstellar dust shells of protoplanetary nebulae. We imaged these protoplanetary nebulae with narrowband filters({delta}{lambda}/{lambda}{=~}10%) at wavelengths of notable dust features. With our typical angular resolution of 1'', we resolve 17 sources, find 48 objects unresolved, and do not detect one source. For several sources we checked optical and infrared associations and positions of the sources. In table format, we list the size and flux measurements for all of the detected objects and show figures of all of the resolved sources. The proto-planetary nebula candidate sample includes, in addition to the predominant proto-planetary nebulae, extreme asymptotic giant branch stars, young planetary nebulae, a supergiant, and a luminous blue variable. We find that dust shells that are cooler (T{=~}150 K) and brighter in the infrared are more easily resolved. Eleven of the seventeen resolved sources are extended and fall into one of two types of MIR morphological classes: core/elliptical or toroidal. Core/elliptical structures show unresolved cores with lower surface brightness elliptical nebulae. Toroidal structures show limb-brightened peaks suggesting equatorial density enhancements. We argue that core/ellipticals have denser dust shells than toroidals.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/434/325
- Title:
- 452 AMIGA galaxies physical parameters
- Short Name:
- J/MNRAS/434/325
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Disentangling processes governing the formation and evolution of galaxies is a fundamental challenge in extragalactic research. In this sense the current belief that galaxies grow by the action of minor mergers makes the study of the stellar mass-size relation in different environments an important tool for distinguishing effects of internal and external processes. The aim of this work is to study the effects of environment on the growth in size of galaxies. As part of AMIGA project (Analysis of the Interstellar Medium of Isolated GAlaxies), we examine the stellar mass-size relation for a sample of the most isolated galaxies in the local Universe interpreted as stellar systems where evolution has been mainly governed by internal processes. Effects of environment on the stellar mass-size relation are evaluated by comparing our results with samples of less isolated early- and late-type galaxies, as well as, for the first time, different spiral subtypes. Stellar masses in our sample were derived by fitting the SED of each galaxy with kcorrect. We used two different size estimators, the half-light radius obtained with SExtractor and the effective radius calculated by fitting a Sersic profile to the i-band image of each galaxy using GALFIT.We found good agreement between those size estimators when the Sersic index fell in the range 2.5<n<4.5 and 0.5<n<2.5 for (visually classified) early- and late-type galaxies respectively.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/L39
- Title:
- AMIGA galaxies structural parameters
- Short Name:
- J/ApJ/788/L39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present structural parameters and (g-i) bulge/disk colors for a large sample (189) of isolated AMIGA galaxies. The structural parameters of bulges were derived from the two-dimensional bulge/disk/bar decomposition of Sloan Digital Sky Survey i-band images using GALFIT. Galaxies were separated between classical bulges (n_b_>2.5) and pseudobulges (n_b_<2.5), resulting in a dominant pseudobulge population (94%) with only 12 classical bulges. In the <{mu}_e_>-R_e_plane, pseudobulges are distributed below the elliptical relation (smaller R_e_ and fainter {mu}_e_), with the closest region to the Kormendy relation populated by those pseudobulges with larger values of B/T. We derived (g-i) bulge colors using aperture photometry and find that pseudobulges show median colors (g-i)_b_~1.06, while their associated disks are much bluer, (g-i)_d_~0.77. Moreover, 64% (113/177) of pseudobulges follow the red sequence of early-type galaxies. Bluer pseudobulges tend to be located in galaxies with the highest likelihood of tidal perturbation. The red bulge colors and low B/T values for AMIGA isolated galaxies are consistent with an early formation epoch and not much subsequent growth. Properties of bulges in isolated galaxies contrast with a picture where pseudobulges grow continuously via star formation. They also suggest that environment could be playing a role in rejuvenating the pseudobulges.
914. AMIGA III. IRAS data
- ID:
- ivo://CDS.VizieR/J/A+A/462/507
- Title:
- AMIGA III. IRAS data
- Short Name:
- J/A+A/462/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the mid- (MIR) and far- (FIR) infrared properties of a large (~1000) sample of the most isolated galaxies in the local Universe. This sample is intended as a "nurture-free" zero point against which more environmentally influenced samples can be compared. We reprocess IRAS MIR/FIR survey data using the ADDSCAN/SCANPI utility for 1030 out of 1050 galaxies from the Catalogue of Isolated Galaxies (CIG, Cat. <VII/82>) as part of the AMIGA survey. We focus on diagnostics (FIR luminosity LFIR , R=log(LFIR/LB) and IRAS colours) thought to be sensitive to effects of environment or interaction.
- ID:
- ivo://CDS.VizieR/J/A+A/449/937
- Title:
- AMIGA. II. Morphological refinement
- Short Name:
- J/A+A/449/937
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a refinement of the optical morphologies for galaxies in the Catalog of Isolated Galaxies (Karachentseva et al., 1973, Cat. <VII/82>) that forms the basis of the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) project. Uniform reclassification using the digitized POSS II data benefited from the high resolution and dynamic range of that sky survey. Comparison with independent classifications made for an SDSS overlap sample of more than 200 galaxies confirms the reliability of the early vs. late-type discrimination and the accuracy of spiral subtypes within {Delta}T=1-2. CCD images taken at the Observatorio de Sierra Nevada (OSN) were also used to solve ambiguities in early versus late-type classifications. A considerable number of galaxies in the catalog (n=193) are flagged for the presence of nearby companions or signs of distortion likely due to interaction. This most isolated sample of galaxies in the local Universe is dominated by two populations: 1) 82% are spirals (Sa-Sd) with the bulk being luminous systems with small bulges (63% between types Sb-Sc) and 2) a significant population of early-type E-S0 galaxies (14%).
- ID:
- ivo://CDS.VizieR/J/A+A/436/443
- Title:
- AMIGA. I. Velocities of CIG galaxies
- Short Name:
- J/A+A/436/443
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AMIGA project (Analysis of the Interstellar Medium of Isolated Galaxies) is compiling a multiwavelength database of isolated galaxies that includes optical (B and H{alpha}), infrared (FIR and NIR) and radio (continuum plus HI and CO lines) properties. It involves a refinement of the pioneering Catalog of Isolated Galaxies (<VII/82>). This paper is the first in a series and begins with analysis of the global properties of the nearly redshift-complete Catalog of Isolated Galaxies (CIG) with emphasis on the Optical Luminosity Function (OLF) which we compare with other recent estimates of the OLF for a variety of environments. The CIG redshift distribution for n=956 galaxies re-enforces the evidence for a bimodal structure seen earlier in smaller samples. The peaks at redshift near 1500 and 6000km/s correspond respectively to galaxies in the local supercluster and those in more distant large-scale components (particularly Perseus- Pisces). The two peaks in the redshift distribution are superimposed on 50% or more of the sample that is distributed in a much more homogeneous way. The CIG probably represents the most homogeneous local field example that has ever been compiled. Our derivation of the CIG OLF is consistent with other studies of the OLF for lower density environments. This comparison via the Schechter parameter formalization shows that: 1) M* increases with galaxy surface density on the sky and 2) {alpha} shows a weaker tendency to do the same. The CIG represents the largest and most complete foundation for studies of isolated galaxies and is likely as close as we can come to a field sample.
- ID:
- ivo://CDS.VizieR/J/A+A/470/505
- Title:
- AMIGA IV. Neighbours around CIG galaxies
- Short Name:
- J/A+A/470/505
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Studies of the effects of environment on galaxy properties and evolution require well defined control samples. Such isolated galaxy samples have up to now been small or poorly defined. The AMIGA project (Analysis of the interstellar Medium of Isolated GAlaxies) represents an attempt to define a statistically useful sample of the most isolated galaxies in the local (z<0.05) Universe. A suitable large sample for the AMIGA project already exists, the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973; 1050 galaxies, Cat. VII/82), and we use this sample as a starting point to refine and perform a better quantification of its isolation properties. Digitised POSS-I E images were analysed out to a minimum projected radius R<0.5Mpc around 950 CIG galaxies (those within Vr=1500km/s were excluded). We identified all galaxy candidates in each field brighter than B=17.5 with a high degree of confidence using the LMORPHO software. We generated a catalogue of approximately 54000 potential neighbours (redshifts exist for 30% of this sample). 666 galaxies pass and 284 fail the original CIG isolation criterion. The available redshift data confirm that our catalogue involves a largely background population rather than physically associated neighbours. We find that the exclusion of neighbours within a factor of 4 in size around each CIG galaxy, employed in the original isolation criterion, corresponds to {Delta}Vr~18000km/s indicating that it was a conservative limit. Galaxies in the CIG have been found to show different degrees of isolation. We conclude that a quantitative measure of this is mandatory. It will be the subject of future work based on the catalogue of neighbours obtained here.
- ID:
- ivo://CDS.VizieR/J/A+A/534/A102
- Title:
- AMIGA IX. Molecular gas properties
- Short Name:
- J/A+A/534/A102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We characterize the molecular gas content (ISM cold phase) using CO emission of a redshift-limited subsample of isolated galaxies from the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) project in order to provide a comparison sample for studies of galaxies in different environments. We present the ^12^CO(1-0) data for 273 AMIGA galaxies, most of them (n=186) from our own observations with the IRAM 30m and the FCRAO 14m telescopes and the rest from the literature. We constructed a redshift-limited sample containing galaxies with 1500km/s<v<5000km/s and excluded objects with morphological evidence of possible interaction. This sample (n=173) is the basis for our statistical analysis. It contains galaxies with molecular gas masses, MH2, in the range of ~10^8^-10^10^M_{sun}_. It is dominated, both in absolute number and in detection rate, by spiral galaxies of type T=3-5 (Sb-Sc). Most galaxies were observed with a single pointing towards their centers. Therefore, we performed an extrapolation to the total molecular gas mass expected in the entire disk based on the assumption of an exponential distribution. We then studied the relationships between MH2 and other galactic properties.
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/3330
- Title:
- AMI Galactic Plane Survey at 16GHz. I.
- Short Name:
- J/MNRAS/429/3330
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AMI Galactic Plane survey is being made with the Arcminute Microkelvin Imager (AMI) Small Array at 15.7GHz and with resolution of approximately 3arcmin. This is the first data release, covering ~868deg^2^ of the Northern Galactic plane between |b|~+/-5{deg} and above {delta}=40{deg} with a noise level of ~3mJy/beam away from bright sources. The source catalogue contains a total of 3503 sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/1396
- Title:
- AMI Galactic Plane Survey at 16GHz. II.
- Short Name:
- J/MNRAS/453/1396
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Arcminute Microkelvin Imager Galactic Plane Survey (AMIGPS) provides mJy-sensitivity, arcminute-resolution interferometric images of the northern Galactic plane at ~16GHz. The first data release covered 76{deg}<=l<=170{deg} between latitudes of |b|<=5{deg}; here we present a second data release, extending the coverage to 53{deg}<=l<=193{deg} and including high-latitude extensions to cover the Taurus and California giant molecular cloud regions, and the recently discovered large supernova remnant G159.6+7.3. The total coverage is now 1777{deg}^2^ and the catalogue contains 6509 sources. We also describe the improvements to the data processing pipeline which improves the positional and flux density accuracies of the survey.
