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4091. Warm molecular hydrogen in ULIRGs
ID:
ivo://CDS.VizieR/J/MNRAS/439/2701
Title:
Warm molecular hydrogen in ULIRGs
Short Name:
J/MNRAS/439/2701
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ultraluminous infrared galaxies (ULIRGs) show on average three times more emission in the rotational transitions of molecular hydrogen than expected based on their star formation rates. Using Spitzer archival data, we investigate the origin of excess warm H_2_ emission in 115 ULIRGs of the IRAS 1Jy sample. We find a strong correlation between H_2_ and [FeII] line luminosities, suggesting that excess H_2_ is produced in shocks propagating within neutral or partially ionized medium. This view is supported by the correlations between H_2_ and optical line ratios diagnostic of such shocks. The galaxies powered by star formation and those powered by active nuclei follow the same relationship between H_2_ and [FeII], with emission line width being the major difference between these classes (~500 and ~1000km/s, respectively). We conclude that excess H_2_ emission is produced as the supernovae and active nuclei drive outflows into the neutral interstellar medium of the ULIRGs. A weak positive correlation between H_2_ and the length of the tidal tails indicates that these outflows are more likely to be encountered in more advanced mergers, but there is no evidence for excess H_2_ produced as a result of the collision shocks during the final coalescence.
4092. Warped disks in spiral galaxies
ID:
ivo://CDS.VizieR/J/other/NewA/11.293
Title:
Warped disks in spiral galaxies
Short Name:
J/other/NewA/11.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have analyzed the disk morphologies of 325 edge-on galaxies to derive the warp statistics in spiral galaxies using Digital Sky Survey. Galaxies were included in our study if their isophotal diameter (D25) satisfied logD25>1, and if their major-to-minor axis ratio was in the range a/b>9.5. We found that 236 out of the 325 sample galaxies (73%) had warps: 165 S-shaped (51%) and 71 U-shaped (22%). We additionally found that the warp properties (warp angles, warp radius, and warp asymmetry) as well as the warp frequency did not depend on galaxy morphology. A quite tight anticorrelation was observed between warp radius and warp amplitude, and a positive correlation was found between warp asymmetry and warp amplitude. A detailed analysis of the relations between warp parameters and galaxy properties revealed that strong warps are mostly caused by tidal interactions, whereas weak warps are formed by a variety of mechanisms including gas accretion. The present results indicate that the fractional warp radius coupled with warp angles representing the warp amplitude and warp curvature provide useful diagnostic indicators of the origin of warps.
4093. Warps in southern hemisphere galaxies
ID:
ivo://CDS.VizieR/J/A+A/399/457
Title:
Warps in southern hemisphere galaxies
Short Name:
J/A+A/399/457
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalog of optical warps of galaxies is presented. This can be considered complementary to that reported by Sanchez-Saavedra et al. (1990MNRAS.246..458S), with 42 galaxies in the northern hemisphere, and to that by Reshetnikov & Combes (1999A&AS..138..101R), with 60 optical warps. The limits of the present catalog are: logr_25_>0.60, B_1_<14.5, DE(2000)<0{deg}, -2.5<t.7. Therefore, lenticular galaxies have also been considered. This catalog lists 150 warped galaxies out of a sample of 276 edge-on galaxies and covers the whole southern hemisphere, except the Avoidance Zone. It is therefore very suitable for statistical studies of warps. It also provides a source guide for detailed particular observations. We confirm the large frequency of warped spirals: nearly all galaxies are warped. The frequency and warp angle do not present important differences for the different types of spirals. However, no lenticular warped galaxy has been found within the specified limits. This finding constitutes an important restriction for theoretical models.
4094. Warps of galaxies
ID:
ivo://CDS.VizieR/J/A+A/391/519
Title:
Warps of galaxies
Short Name:
J/A+A/391/519
Date:
21 Oct 2021
Publisher:
CDS
Description:
From a comparison of the different parameters of warped galaxies in the radio, and especially in the visible, we find that: a) No large galaxy (large mass or radius) has been found to have high amplitude in the warp, and there is no correlation of size/mass with the degree of asymmetry of the warp. b) The disc density and the ratio of dark to luminous mass show an opposing trend: smaller values give more asymmetric warps in the inner radii (optical warps) but show no correlation with the amplitude of the warp; however, in the external radii is there no correlation with asymmetry. c) A third anticorrelation appears in a comparison of the amplitude and degree of asymmetry in the warped galaxies. Hence, it seems that very massive dark matter haloes have nothing to do with the formation of warps but only with the degree of symmetry in the inner radii, and are unrelated to the warp shape for the outermost radii. Denser discs show the same dependence.
4095. Washington photometry of Bootes I stars
ID:
ivo://CDS.VizieR/J/AJ/136/2321
Title:
Washington photometry of Bootes I stars
Short Name:
J/AJ/136/2321
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Washington CT_1_T_2_ photometry of a field central to the Bootes I dwarf spheroidal galaxy, which was discovered as a stellar overdensity in the Sloan Digital Sky Survey (DR5). We show that the Washington filters are much more effective than the Sloan filters in separating the metal-poor turn-off stars in the dwarf galaxy from the foreground stars. We detect 165 objects in the field, and statistically determine that just over 40% of the objects are nonmembers. Our statistical analysis mostly agrees with radial velocity measurements of the brighter stars. We find that there is a distinct main-sequence turn-off and subgiant branch, where there is some evidence of a spread in chemical abundance.
4096. Water masers in M31. II. Multiwavelength data
ID:
ivo://CDS.VizieR/J/ApJ/826/136
Title:
Water masers in M31. II. Multiwavelength data
Short Name:
J/ApJ/826/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a comparative multiwavelength analysis of water-maser-emitting regions and non-maser-emitting luminous 24{mu}m star-forming regions in the Andromeda Galaxy (M31) to identify the sites most likely to produce luminous water masers useful for astrometry and proper motion studies. Included in the analysis are Spitzer 24{mu}m photometry, Herschel 70 and 160{mu}m photometry, H{alpha} emission, dust temperature, and star-formation rate. We find significant differences between the maser-emitting and non-maser-emitting regions: water-maser-emitting regions tend to be more infrared-luminous and show higher star-formation rates. The five water masers in M31 are consistent with being analogs of water masers in Galactic star-forming regions and represent the high-luminosity tail of a larger (and as yet undetected) population. Most regions likely to produce water masers bright enough for proper motion measurements using current facilities have already been surveyed, but we suggest three ways to detect additional water masers in M31: (1) reobserve the most luminous mid- or far-infrared sources with higher sensitivity than was used in the Green Bank Telescope survey; (2) observe early-stage star-forming regions selected by millimeter continuum that have not already been selected by their 24{mu}m emission, and (3) reobserve the most luminous mid- or far-infrared sources and rely on maser variability for new detections.
4097. WeCAPP Survey. M31 variables
ID:
ivo://CDS.VizieR/J/A+A/445/423
Title:
WeCAPP Survey. M31 variables
Short Name:
J/A+A/445/423
Date:
21 Oct 2021
Publisher:
CDS
Description:
The observations in the WeCAPP microlensing survey towards the Andromeda galaxy (M31) for a period of three years (2000-2003) resulted in a database with unprecedented time coverage for an extragalactic variable star study. We have monitored a 16.1' x 16.6' field centered on the nucleus of M31 in two optical bands (R and I) using the 0.8-m telescope at Wendelstein, Germany and the 1.2-m telescope at Calar Alto, Spain. Using the difference imaging method we detected 23781 variable sources for which we calculated the periods and variation amplitudes. We classified the variables according to their position in the R-band period-amplitude plane. Three groups can be distinguished; while the first two groups can be mainly associated with Cepheid-like variables (population I Cepheids in group I; type II Cepheids and RV Tauri stars in group II), the third one consists of Long Period Variables (LPVs). We detected 37 RV Tauri stars and 11 RV Tauri candidates, which makes this catalogue one of the largest collections of this class of stars to date. The classification scheme is supported by Fourier decomposition of the light curves. The catalogue of variable stars contains the positions, the periods in R and I, the significance of the assigned periods, and the variation amplitudes in the R and I bands.
4098. WERGS. II. SED fitting with optical, IR & radio data
ID:
ivo://CDS.VizieR/J/ApJS/243/15
Title:
WERGS. II. SED fitting with optical, IR & radio data
Short Name:
J/ApJS/243/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present physical properties of radio galaxies (RGs) with f_1.4GHz_>1mJy discovered by Subaru Hyper Suprime-Cam (HSC) and Very Large Array Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. For 1056 FIRST RGs at 0<z<=1.7 with HSC counterparts in about 100deg^2^, we compiled multi-wavelength data of optical, near-infrared (IR), mid-IR, far-IR, and radio (150MHz). We derived their color excess (E(B-V)_*_), stellar mass, star formation rate (SFR), IR luminosity, the ratio of IR and radio luminosity (q_IR_), and radio spectral index ({alpha}_radio_) that are derived from the spectral energy distribution (SED) fitting with CIGALE. We also estimated Eddington ratio based on stellar mass and integration of the best-fit SEDs of active galactic nucleus (AGN) component. We found that E(B-V)_*_, SFR, and IR luminosity clearly depend on redshift while stellar mass, q_IR_, and {alpha}_radio_ do not significantly depend on redshift. Since optically faint (i_AB_>=21.3) RGs that are newly discovered by our RG survey tend to be high redshift, they tend to not only have a large dust extinction and low stellar mass but also have high SFR and AGN luminosity, high IR luminosity, and high Eddington ratio compared with optically bright ones. The physical properties of a fraction of RGs in our sample seem to differ from a classical view of RGs with massive stellar mass, low SFR, and low Eddington ratio, demonstrating that our RG survey with HSC and FIRST provides us curious RGs among entire RG population.
4099. Wide-Angle-Tailed radio galaxies redshifts
ID:
ivo://CDS.VizieR/J/AJ/120/2269
Title:
Wide-Angle-Tailed radio galaxies redshifts
Short Name:
J/AJ/120/2269
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new redshifts and positions for 635 galaxies in nine rich clusters containing wide-angle tailed (WAT) radio galaxies. Combined with existing data, we now have a sample of 18 WAT-containing clusters with more than 10 redshifts. This sample contains a substantial portion of the WAT clusters in the VLA 20 cm survey of Abell clusters, including 75% of WAT clusters in the complete survey (z<=0.09), and 20% of WAT clusters with z>0.09. It is a representative sample, which should not contain biases other than selection by radio morphology. We graphically present the new data using histograms and sky maps. A semiautomated procedure is used to search for emission lines in the spectra in order to add and verify galaxy redshifts. We find that the average apparent fraction of emission-line galaxies is about 9% in both the clusters and the field. We investigate the magnitude completeness of our redshift surveys with CCD data for a test case, Abell 690. This case indicates that our galaxy target lists are deeper than the detection limit of a typical MX exposure, and they are 82% complete down to R=19.0. The importance of the uniformity of the placement of fibers on targets is posited, and we evaluate this in our data sets. We find some cases of nonuniformities which may influence dynamical analyses. A second paper will use this database to look for correlations between the WAT radio morphology and the cluster's dynamical state.
4100. Wide field imagers ground-based astrometry. V.
ID:
ivo://CDS.VizieR/J/A+A/563/A80
Title:
Wide field imagers ground-based astrometry. V.
Short Name:
J/A+A/563/A80
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-precision astrometry requires accurate point-spread function modeling and accurate geometric-distortion corrections. This paper demonstrates that it is possible to achieve both requirements with data collected at the High Acuity Wide-field K-band Imager (HAWK-I); a wide-field imager installed at the Nasmyth focus of UT4/VLT ESO 8m telescope. Our final astrometric precision reaches ~3mas per coordinate for a well exposed star in a single image, with a systematic error less than 0.1mas. We constructed calibrated astro-photometric catalogs and atlases of 7 fields: the Baade's window, NGC 6656, NGC 6121, NGC 6822, NGC 6388, NGC 104, and the James Webb Space Telescope calibration field (in the LMC). We make these catalogs and images electronically available to the community. Furthermore, as a demonstration of the efficacy of our approach, combining archival material taken with the optical wide-field imager at the MPI/ESO 2.2m with HAWK-I observations, we are able to achieve an excellent separation between cluster members and field objects for NGC 6656 and NGC 6121 with a time base-line of about 8 years. Using both HST and HAWK-I data, we also study the radial distribution of the SGB populations in NGC 6656 and conclude that the radial trend is flat, within our uncertains. We also provide membership probabilities for most of the stars in NGC 6656 and NGC 6121 catalogs and estimate membership for the published variable stars in these two fields.