- ID:
- ivo://CDS.VizieR/J/A+A/611/A38
- Title:
- Hints for a bar in M31 kinematics and morphology
- Short Name:
- J/A+A/611/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As the nearest large spiral galaxy, M 31 provides a unique opportunity to study the structure and evolutionary history of this galaxy type in great detail. Among the many observing programs aimed at M 31 are microlensing studies, which require good three-dimensional models of the stellar mass distribution. Possible non-axisymmetric structures like a bar need to be taken into account. Due to M 31's high inclination, the bar is difficult to detect in photometry alone. Therefore, detailed kinematic measurements are needed to constrain the possible existence and position of a bar in M 31. We obtained ~=220 separate fields with the optical integral-field unit spectrograph VIRUS-W, covering the whole bulge region of M 31 and parts of the disk. We derived stellar line-of-sight velocity distributions from the stellar absorption lines, as well as velocity distributions and line fluxes of the emission lines H{beta}, [OIII] and [NI]. Our data supersede any previous study in terms of spatial coverage and spectral resolution. We find several features that are indicative of a bar in the kinematics of the stars, we see intermediate plateaus in the velocity and the velocity dispersion, and correlation between the higher moment h3 and the velocity. The gas kinematics is highly irregular, but is consistent with non-triaxial streaming motions caused by a bar. The morphology of the gas shows a spiral pattern, with seemingly lower inclination than the stellar disk. We also look at the ionization mechanisms of the gas, which happens mostly through shocks and not through starbursts.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/112/429
- Title:
- HI observations in Her Supercluster
- Short Name:
- J/A+AS/112/429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This part of the HI redshift survey in the region of the Hercules Supercluster presents HI spectra of 84 galaxies selected from the UGC and CGCG with extends in the previously begun survey of late-type spiral galaxies in that region. Measured HI parameters from the spectra are given.
- ID:
- ivo://CDS.VizieR/J/PAZh/31/563
- Title:
- HI observations of flat galaxies
- Short Name:
- J/PAZh/31/563
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of HI observations with the 100-m Effelsberg radio telescope are presented for 94 edge-on spiral galaxies from the Revised Flat Galaxy Catalog (Karachentsev et al., 1999, Cat. <VII/219>) and 14 galaxies from the 2MASS-selected Flat Galaxy Catalog (Mitronova et al., 2004, Bull. Spec. Astron. Obs. Russ. Acad. Sci. 57, 5). The HI line fluxes, heliocentric radial velocities and the HI line widths are given for 65 detected galaxies. Their HI profiles are shown as a mosaic. We calculated some global parameters of the galaxies and discuss linear correlations between them. Total (indicative) mass-to-luminosity ratio for the sample galaxies is ranked within 0.4-8.2 with the mean value 3.8 (M_{sun}_/L_{sun}_), and the mean fraction of hydrogen mass is 0.13. For 43 undetected objects their rms noise is also given.
- ID:
- ivo://CDS.VizieR/J/A+A/365/1
- Title:
- HI observations of LSB galaxies
- Short Name:
- J/A+A/365/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Nancay Radio Telescope to obtain new global HI data for 16 giant low surface brightness (LSB) galaxies. Our targets have optical luminosities and disk scale lengths at the high end for spiral galaxies (L_B_~10^10^L_{sun}_ and h_r_>6kpc for H_0_=75km/s/Mpc), but they have diffuse stellar disks, with mean disk surface brightnesses >1 magnitude fainter than normal giant spirals. Thirteen of the galaxies previously had been detected in HI by other workers, but the published HI observations were either confused, resolved by the telescope beam, of low signal-to-noise, or showed significant discrepancies between different authors. For the other 3 galaxies, no HI data were previously available. Several of the galaxies were resolved by the Nancay 3.6' E-W beam, so global parameters were derived from multiple-point mapping observations. Typical HI masses for our sample are >10^10^M_{sun}_, with M_HI_/L_B_=0.3-1.7 (in solar units). All of the observed galaxies have published optical surface photometry, and we have compiled key optical measurements for these objects from the literature. We frequently find significant variations among physical parameters of giant LSB galaxies reported by various workers.
- ID:
- ivo://CDS.VizieR/J/A+A/366/428
- Title:
- HI observations of nearby dwarf galaxies
- Short Name:
- J/A+A/366/428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out a systematic search for nearby dwarf galaxies in the northern sky based on POSS-II film copies. As a result we present a list of 101 nearby dwarf galaxy candidates mainly of low surface brightness which have angular diameters a>0.5'. About two thirds of the objects are new discoveries. This sample is considered as a supplement to the 163 northern dwarf galaxy candidates (1998, Cat., <J/A+AS/127/409>) which have been detected in the same declination range around the known Local Volume galaxies and to the 78 dwarf galaxy candidates (1999A&AS..135..221K) in the Local Void region. All the galaxies were observed in HI with the 100-m Effelsberg radio telescope with a detection rate of 46%. The sample of detected galaxies has the following median parameters: radial velocity V_LG_=+770km/s, HI line width W_50_=46km/s, absolute blue magnitude M_B_=-13.8mag, linear diameter A_0_=2.7kpc, hydrogen mass-to-luminosity ratio M_HI_/L_B_=1.2M_{sun}_/L_{sun}_, and the HI mass-to-total mass ratio M_HI_/M_t_=0.28.
- ID:
- ivo://CDS.VizieR/J/A+A/442/137
- Title:
- HI observations of WHISP disk galaxies
- Short Name:
- J/A+A/442/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present HI observations of 68 early-type disk galaxies from the WHISP survey. They have morphological types between S0 and Sab and absolute B-band magnitudes between -14 and -22. These galaxies form the massive, high surface-brightness extreme of the disk galaxy population, few of which have been imaged in HI before. The HI properties of the galaxies in our sample span a large range; the average values of MHI/LB and DHI/D25 are comparable to the ones found in later-type spirals, but the dispersions around the mean are larger. No significant differences are found between the S0/S0a and the Sa/Sab galaxies.
- ID:
- ivo://CDS.VizieR/VIII/73
- Title:
- HI Parkes All Sky Survey Catalogue (HIPASS)
- Short Name:
- VIII/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The HI Parkes All-Sky Survey (HIPASS) Catalogue forms the largest uniform catalogue of HI sources compiled to date, with 4315 sources identified purely by their HI content. The catalogue data comprise the southern region DE<+2{deg} of HIPASS, the first blind HI survey to cover the entire southern sky. RMS noise for this survey is 13mJy/beam and the velocity range is -1280 to 12700km/s. Data search, verification and parametrization methods are discussed along with a description of measured quantities. Full catalogue data is made available to the astronomical community including positions, velocities, velocity widths, integrated fluxes and peak flux densities. Also available are on-sky moment maps, position- velocity moment maps and spectra of catalogue sources. A number of local large-scale features are observed in the space distribution of sources including the Super-Galactic plane and the Local Void. Notably, large-scale structure is seen at low Galactic latitudes, a region normally obscured at optical wavelengths.
- ID:
- ivo://CDS.VizieR/J/AJ/129/220
- Title:
- HI Parkes Zone of Avoidance Survey
- Short Name:
- J/AJ/129/220
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the Northern extension of the HI Parkes Zone of Avoidance Survey, a blind HI survey utilizing the multibeam receiver on the Parkes 64m telescope. In the two regions studied here, l=36{deg}-52{deg} and l=196{deg}-212{deg}, |b|<=5{deg}, we have detected 77 HI galaxies, 20 of which have been previously detected in HI. The survey has a median rms noise of 6.0mJy/beam and is complete to a mean flux density of 22mJy. We have searched for multiwavelength counterparts to the 77 galaxies detected here: 19, 27, and 11 have a likely optical, 2MASS (Cat. <VII/233>), and IRAS (Cat. <II/125>) cataloged counterpart, respectively.
679. HIPASS in Fornax
- ID:
- ivo://CDS.VizieR/J/MNRAS/337/641
- Title:
- HIPASS in Fornax
- Short Name:
- J/MNRAS/337/641
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using data from the HI Parkes All Sky Survey (HIPASS), we have searched for neutral hydrogen in galaxies in a region <25x25{deg}^2^ centred on NGC 1399, the nominal centre of the Fornax cluster. Within a velocity search range of 300-3700km/s and to a 3 lower flux limit of ~40mJy, 110 galaxies with HI emission were detected, one of which is previously uncatalogued. None of the detections has early-type morphology. Previously unknown velocities for 14 galaxies have been determined, with a further four velocity measurements being significantly dissimilar to published values. Identification of an optical counterpart is relatively unambiguous for more than ~90 per cent of our HI galaxies. The galaxies appear to be embedded in a sheet at the cluster velocity which extends for more than 30across the search area. At the nominal cluster distance of ~20Mpc, this corresponds to an elongated structure more than 10Mpc in extent. A velocity gradient across the structure is detected, with radial velocities increasing by ~500km/s from south-east to north-west. The clustering of galaxies evident in optical surveys is only weakly suggested in the spatial distribution of our HI detections. Of 62 HI detections within a 10{deg} projected radius of the cluster centre, only two are within the core region (projected radius <1{deg}) and less than 30 per cent are within 3.5{deg}, suggesting a considerable deficit of HI-rich galaxies in the centre of the cluster. However, relative to the field, there is a 3(+/-1)-fold excess of HI-rich galaxies in the outer parts of the cluster where galaxies may be infalling towards the cluster for the first time.
- ID:
- ivo://CDS.VizieR/J/A+A/464/377
- Title:
- HIP binaries with radial velocities
- Short Name:
- J/A+A/464/377
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The comparison of the proper motions constructed from positions spanning a short (Hipparcos) or long time (Tycho-2) makes it possible to uncover binaries with periods of the order of or somewhat larger than the short time span (in this case, the 3 yr duration of the Hipparcos mission), since the unrecognised orbital motion will then add to the proper motion. A list of candidate proper motion binaries is constructed from a chi-square test evaluating the statistical significance of the difference between the Tycho-2 and Hipparcos proper motions for 103134 stars in common between the two catalogues (excluding components of visual systems). The present paper focuses on the evaluation of the detection efficiency of proper-motion binaries, using different kinds of control data (mostly radial velocities). The detection rate for entries from the Ninth Catalogue of Spectroscopic Binary Orbits (SB9) is evaluated, as well as for stars like barium stars, which are known to be all binaries, and finally for spectroscopic binaries identified from radial velocity data in the Geneva-Copenhagen survey of F and G dwarfs in the solar neighbourhood. Proper motion binaries are efficiently detected for systems with parallaxes in excess of 20mas, and periods in the range 1000-30000d. The shortest periods in this range (1000-2000d, i.e., once to twice the duration of the Hipparcos mission) may appear only as DMSA/G binaries (accelerated proper motion in the Hipparcos Double and Multiple System Annex). Proper motion binaries detected among SB9 systems having periods shorter than about 400d hint at triple systems, the proper-motion binary involving a component with a longer orbital period. A list of 19 candidate triple systems is provided. Binaries suspected of having low-mass (brown-dwarf-like) companions are listed as well. Among the 37 barium stars with parallaxes larger than 5mas, only 7 exhibit no evidence for duplicity whatsoever (be it spectroscopic or astrometric). Finally, the fraction of proper-motion binaries shows no significant variation among the various (regular) spectral classes, when due account is taken for the detection biases.