- ID:
- ivo://CDS.VizieR/J/ApJ/899/158
- Title:
- Gas structure comparison; NGC 253 and Milky Way
- Short Name:
- J/ApJ/899/158
- Date:
- 14 Mar 2022 07:10:20
- Publisher:
- CDS
- Description:
- We compare molecular gas properties in the starbursting center of NGC253 and the Milky Way Galactic center (GC) on scales of ~1-100pc using dendrograms and resolution-, area-, and noise-matched data sets in CO(1-0) and CO(3-2). We find that the size-line width relations in NGC253 and the GC have similar slope, but NGC253 has larger line widths by factors of ~2-3. The {sigma}2/R dependency on column density shows that, in the GC, on scales of 10-100pc the kinematics of gas over N>3x1021/cm^2^ are compatible with gravitationally bound structures. In NGC253 this is only the case for column densities N>3x1022/cm^2^. The increased line widths in NGC253 originate in the lower column density gas. This high velocity dispersion, not gravitationally self-bound gas, is likely in transient structures created by the combination of high average densities and feedback in the starburst. The high densities turn the gas molecular throughout the volume of the starburst, and the injection of energy and momentum by feedback significantly increases the velocity dispersion at a given spatial scale over what is observed in the GC.
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- ID:
- ivo://CDS.VizieR/J/ApJ/776/74
- Title:
- GASS VII. Bivariate HI-stellar mass function
- Short Name:
- J/ApJ/776/74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the bivariate neutral atomic hydrogen (HI)-stellar mass function (HISMF) {phi}(M_HI_, M_{star}_) for massive (logM_*_/M_{sun}_>10) galaxies derived from a sample of 480 local (0.025<z<0.050) galaxies observed in H I at Arecibo as part of the GALEX Arecibo SDSS Survey. We fit six different models to the HISMF and find that a Schechter function that extends down to a 1% HI gas fraction, with an additional fractional contribution below that limit, is the best parameterization of the HISMF. We calculate {Omega}_HI,M_{star}__>10^10^ and find that massive galaxies contribute 41% of the H I density in the local universe. In addition to the binned HISMF, we derive a continuous bivariate fit, which reveals that the Schechter parameters only vary weakly with stellar mass: M_HI_^*^, the characteristic H I mass, scales as M_{star}_^0.39^; {alpha}, the slope of the HISMF at moderate H I masses, scales as M_{star}_^0.07^; and f, the fraction of galaxies with HI gas fraction greater than 1%, scales as M_{star}_^-0.24^. The variation of f with stellar mass should be a strong constraint for numerical simulations. To understand the physical mechanisms that produce the shape of the HISMF, we redefine the parameters of the Schechter function as explicit functions of stellar mass and star formation rate (SFR) to produce a trivariate fit. This analysis reveals strong trends with SFR. While M_HI_^*^ varies weakly with stellar mass and SFR (M_HI_^*^{prop.to}M_{star}_^0.22^, M_HI_^*^{prop.to}SFR^-0.03^), {alpha} is a stronger function of both stellar mass and especially SFR ({alpha}{prop.to}M_{star}_^0.47^, {alpha}{prop.to}SFR^0.95^). The HISMF is a crucial tool that can be used to constrain cosmological galaxy simulations, test observational predictions of the H I content of populations of galaxies, and identify galaxies whose properties deviate from average trends.
- ID:
- ivo://CDS.VizieR/J/A+A/440/107
- Title:
- Gas velocity curve along five spiral galaxies
- Short Name:
- J/A+A/440/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the minor-axis kinematics of ionized gas and stars for a sample of 5 spiral galaxies, which are characterized by either a zero or a shallow gas velocity gradient along their major axis. The asymmetric velocity profiles observed along the minor axis of NGC 4064 and NGC 4189 can be explained as due to the presence of a bar. This is also the case of NGC 4178 where the innermost portion of the gaseous disk is nearly face on. In NGC 4424 and NGC 4941, we measured non-zero gas velocities only in the central regions along the minor axis and gas velocities drop to zero at larger radii. This kinematic feature is suggestive of the presence of an orthogonally-rotating gaseous component which is confined in the innermost regions (i.e. an inner polar disk) to be confirmed with integral-field spectroscopy.
- ID:
- ivo://CDS.VizieR/J/MNRAS/443/1044
- Title:
- GBT HI observations of 1194 spirals
- Short Name:
- J/MNRAS/443/1044
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present HI 21cm observations of 1194 galaxies out to a redshift of 10000km/s selected as inclined spirals (i>~60{deg}) from the 2MASS redshift survey. These observations were carried out at the National Radio Astronomy Observatory Robert C. Byrd Green Bank Telescope (GBT). This observing programme is part of the 2MASS Tully-Fisher (2MTF) survey. This project will combine Hi widths from these GBT observations with those from further dedicated observing at the Parkes Telescope, from the Arecibo Legacy Fast Arecibo L-band Feed Array survey at Arecibo, and S/N>10 and spectral resolution v_res_<10km/s published widths from a variety of telescopes. We will use these Hi widths along with 2MASS photometry to estimate Tully-Fisher distances to nearby spirals and investigate the peculiar velocity field of the local Universe. In this paper, we report on detections of neutral hydrogen in emission in 727 galaxies, and measure good signal to noise and symmetric HI global profiles suitable for use in the Tully-Fisher relation in 484.
- ID:
- ivo://CDS.VizieR/J/ApJ/902/39
- Title:
- GBT HI obs. of ultradiffuse galaxies
- Short Name:
- J/ApJ/902/39
- Date:
- 10 Mar 2022 13:55:53
- Publisher:
- CDS
- Description:
- We present neutral hydrogen (HI) observations using the Robert C. Byrd Green Bank Telescope (GBT) of 70 optically detected UDG candidates in the Coma region from the Systematically Measuring Ultra-Diffuse Galaxies survey (SMUDGes). We detect HI in 18 targets, confirming nine to be gas-rich UDGs and the remainder to be foreground dwarfs. None of our HI-detected UDGs are Coma Cluster members and all but one are in low-density environments. The HI-detected UDGs are bluer and have more irregular morphologies than the redder, smoother candidates not detected in HI, with the combination of optical color and morphology being a better predictor of gas richness than either parameter alone. There is little visual difference between the gas-rich UDGs and the foreground dwarfs in the SMUDGes imaging, and distances are needed to distinguish between them. We find that the gas richnesses of our HI-confirmed UDGs and those from other samples scale with their effective radii in two stellar mass bins, possibly providing clues to their formation. We attempt to place our UDGs on the baryonic Tully-Fisher relation (BTFR) using optical ellipticities and turbulence-corrected HI line widths to estimate rotation velocities, but the potential systematics associated with fitting smooth Sersic profiles to clumpy, low-inclination disks of low surface brightness precludes a meaningful analysis of potential BTFR offsets. These observations are a pilot for a large campaign now under way at the GBT to use the HI properties of gas-rich UDGs to quantitatively constrain how these galaxies form and evolve.
- ID:
- ivo://CDS.VizieR/J/AJ/153/114
- Title:
- GCs in 27 nearby ETGs from the SLUGGS survey
- Short Name:
- J/AJ/153/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Here, we present positions and radial velocities for over 4000 globular clusters (GCs) in 27 nearby early-type galaxies from the SLUGGS survey. The SLUGGS survey is designed to be representative of elliptical and lenticular galaxies in the stellar mass range 10<logM_*_/M_{sun}_<11.7. The data have been obtained over many years, mostly using the very stable multi-object spectrograph DEIMOS on the Keck II 10 m telescope. Radial velocities are measured using the calcium triplet lines, with a velocity accuracy of +/-10-15 km/s. We use phase space diagrams (i.e., velocity-position diagrams) to identify contaminants such as foreground stars and background galaxies, and to show that the contribution of GCs from neighboring galaxies is generally insignificant. Likely ultra-compact dwarfs are tabulated separately. We find that the mean velocity of the GC system is close to that of the host galaxy systemic velocity, indicating that the GC system is in overall dynamical equilibrium within the galaxy potential. We also find that the GC system velocity dispersion scales with host galaxy stellar mass, in a similar manner to the Faber-Jackson relation for the stellar velocity dispersion. Publication of these GC radial velocity catalogs should enable further studies in many areas, such as GC system substructure, kinematics, and host galaxy mass measurements.
- ID:
- ivo://CDS.VizieR/J/AJ/127/2455
- Title:
- Gemini Deep Deep Survey (GDDS)
- Short Name:
- J/AJ/127/2455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Gemini Deep Deep Survey (GDDS) is an ultradeep (K<20.6mag, I<24.5mag) redshift survey targeting galaxies in the "redshift desert" between z=1 and z=2. The primary goal of the survey is to constrain the space density at high redshift of evolved high-mass galaxies. We obtained 309 spectra in four widely separated 30-arcmin^2^ fields using the Gemini North telescope and the Gemini Multi-Object Spectrograph (GMOS). The spectra define a one-in-two sparse sample of the reddest and most luminous galaxies near the I-K versus I color-magnitude track mapped out by passively evolving galaxies in the redshift interval 0.8<z<1.8. This sample is augmented by a one-in-seven sparse sample of the remaining high-redshift galaxy population. The GMOS spectrograph was operating in a nod-and-shuffle mode, which enabled us to remove sky contamination with high precision, even for typical exposures times of 20-30hr per field. The resulting spectra are the deepest ever obtained. In this paper we present our sample of 309 spectra, along with redshifts, identifications of spectral features, and photometry. This makes the GDDS the largest and most complete infrared-selected survey probing the redshift desert. The seven-band (VRIz'JHK_s_) photometry is taken from the Las Campanas Infrared Survey (Cat. <VII/228>).
- ID:
- ivo://CDS.VizieR/J/ApJ/858/102
- Title:
- Gemini/NIFS and HST obs. of the galaxy M59-UCD3
- Short Name:
- J/ApJ/858/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the internal properties of the most massive ultracompact dwarf galaxy (UCD), M59-UCD3, by combining adaptive-optics-assisted near-IR integral field spectroscopy from Gemini/NIFS and Hubble Space Telescope (HST) imaging. We use the multiband HST imaging to create a mass model that suggests and accounts for the presence of multiple stellar populations and structural components. We combine these mass models with kinematics measurements from Gemini/NIFS to find a best-fit stellar mass-to-light ratio (M/L) and black hole (BH) mass using Jeans anisotropic models (JAMs), axisymmetric Schwarzschild models, and triaxial Schwarzschild models. The best-fit parameters in the JAM and axisymmetric Schwarzschild models have BHs between 2.5 and 5.9 million solar masses. The triaxial Schwarzschild models point toward a similar BH mass but show a minimum {chi}^2^ at a BH mass of ~0. Models with a BH in all three techniques provide better fits to the central V_rms_ profiles, and thus we estimate the BH mass to be 4.2_-1.7_^+2.1^x10^6^M_{sun}_ (estimated 1{sigma} uncertainties). We also present deep radio imaging of M59-UCD3 and two other UCDs in Virgo with dynamical BH mass measurements, and we compare these to X-ray measurements to check for consistency with the fundamental plane of BH accretion. We detect faint radio emission in M59cO but find only upper limits for M60-UCD1 and M59-UCD3 despite X-ray detections in both these sources. The BH mass and nuclear light profile of M59-UCD3 suggest that it is the tidally stripped remnant of a ~10^9^-10^10^M_{sun}_ galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJS/174/136
- Title:
- GEMS survey data and catalog
- Short Name:
- J/ApJS/174/136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the data reduction and object cataloging for the GEMS survey, a large-area (800 arcmin^2^) two-band (F606W and F850LP) imaging survey with the Advanced Camera for Surveys on the Hubble Space Telescope, centered on the Chandra Deep Field-South.
- ID:
- ivo://CDS.VizieR/VII/206
- Title:
- General Photometry of Galaxies
- Short Name:
- VII/206
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The tables presented here give the catalogue of aperture photometry of galaxies (UBVRI), the associated bibliography, the weight and systematic corrections applied to individual datasets. A table give the results of the growth curve fits; the net of curves adopted is a linear interpolation between the de Vaucouleurs (r^1/4^) and exponential laws. This aperture photometry has three different origins: (i) an update of the catalogue of Buta et al. 1995 (Cat. <J/AJ/109/517>) (ii) published photometric profiles and (iii) aperture photometry performed on CCD images. Fitting growth curves to aperture photometry of galaxies, in UBVRI, we derive (1) the total magnitude, (2) the effective radius, (3) the color indices and (4) gradients and (5) the photometric type of 5066 galaxies. The photometric type is defined to statistically match the revised morphologic type (numerically coded from -6 to +10) and represents the shape of the growth curve. The catalogue is maintained up-to-date in the database HYPERCAT (http://www-obs.univ-lyon1.fr/~prugniel/cgi-bin/hypercat/). This catalogue supersedes the Longo and de Vaucouleurs (1983) catalogue <VII/167>.
